Health Science I

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Unit 1- Body Tissues

Tissues- A group of cells similar in structure and perform common or related functions

4 Types of Tissues: Epithelial, Connective, Muscle, and Nervous tissues

Epithelial Tissue

Epithelial tissue- Composed of epithelium attached to a layer of connective tissue. The lining gastrointestinal tract and other hollow organs like the skin surface in the epidermis, cover the inside and outside body surfaces.

Usually, epithelial tissue is tightly packed as a way to form a protective barrier (skin, organ lining).

Since epithelial don’t have a vascular supply they are attached to a layer of connective tissue, epithelial get their nutrients from connective tissues which are connected underneath them, and have blood vessels that provide nutrients.

Functions

• Protection- the skin protects is from physical and chemical injuries and microbial infections

• Absorption- stomach and intestinal lining absorb nutrients during digestion.

• Filtration and Extraction- Kidneys get rid of excess waste

• Secretion- Make us the glands that synthesize fluid and hormones for the body and secrete them

  

• Sensory Perception- From stimuli if it’s innervated by nerves.

Classification

Epithelial Tissue can be classified by their Cell Shape and Cell Arrangement.

Cell Shape:

• Squamous- Flat and scale-like

• Cuboidal- Cube- Shaped

• Columnar- Tall, and elongated cells

Cell Arrangement:

• Simple- A single layer of cells thick for absorption and filtration, forms a solid layer of cells lining blood vessels and organs and functions with filtration and diffusion.

• Stratified- Stacked cell layers that work best for protection, from the epidermis

Types:

• simple columnar- one cell thick, found in the lining of the digestive tract, functions with reabsorption and secretion

• stratified columnar- multiple layers thick, rare, and found in few locations in portions of the pharynx and larynx,

• Mucous Membrane- a composite of connective and epithelial tissues. Sometimes called mucosae, these epithelial membranes line the body cavities and hollow passageways that open to the external environment and include the digestive, respiratory, excretory, and reproductive tracts.

  • Mucous- Mucus, produced by the epithelial exocrine glands, covers the epithelial layer.

• Serous Membrane- The outer lining of organs and body cavities of the abdomen and chest, including the stomach. Made up of two layers

• The parietal layer- lines the walls of the body cavity. (Outer layer)

“Pariet-” refers to a cavity wall.

• Visceral layer- covers the organ (the viscera). (Inner layer)

“Viscera-” refers to organ.

What Does It Make?

Epithelial Tissue makes up the Endocrine Glands and Exocrine Glands

• Exocrine Glands- release their substances to the surface of the body (sweat glands located deep in the skin but what they produce is released to the surface)

• Endocrine Glands- ductless glands, as ducts are lost during development, produce hormones and then released to the interstitial space around the cells, they will diffuse into nearby capillaries and then be carried around the body until they reach their target organ (thyroid glands, islet cells of pancreas)

Muscle Tissue

Muscle tissue that allows movement (voluntary control). They respond to a stimulus. As Cardiac muscle doesn’t allow for voluntary movement.

Skeletal Muscle- Voluntary movement, muscled bundles that attach to bones for movement. Usually found in large body muscles (biceps, Hamstrings)

Smooth Muscle- Involuntary movement, function is to move blood, food, and waste through the body's organs. Forms the contractile component of the digestive, urinary, and reproductive systems as well as the airways and arteries

Cardiac Muscle- Involuntary movement, controls synchronized contraction of the heart to produce the heartbeat and is found ONLY in the heart walls

Nervous Tissue

Found in the brain, spinal cord, and nerves (the main component of the nervous system)

Function

Function as being excitable and capable of sending and receiving electrochemical signals that provide the body with information. As Neurons are the main component of nervous tissue along with neuroligins, sending and receiving action potentials as signals across the body

Connective Tissue

composed of cells closely packed with little or no extracellular space in between, connective tissue cells are dispersed in a matrix. Connective tissues come in a vast variety of forms, they typically have in common three characteristic components: cells, large amounts of amorphous ground substance, and protein fibers.

Extracellular Matrix- consists of living and nonliving substances called the “ground substance”. It can have various consistencies such as fluids, solids, gel-like, or very hard. It is mainly found in the connective tissues.

Functions

• Connects- binds and supports structures

• Protects- cushions organs and tissues

• Extracellular matrix- can bear weight, stretch, and take abuse

• Adipose- Insulates and stores fats, fills up space

• Blood- Transport nutrients and substances

• Bone- Provides framework and protection of our organs

Module 2 - Anatomical Structural Organization

Anatomists and healthcare providers use terminology that can be bewildering. However, the purpose of this language is not to confuse, but rather to increase precision and reduce medical errors. Using precise anatomical terminology, we eliminate ambiguity.

Anatomical Positions

To further increase precision, anatomists standardize the way in which they view the body.

There are 5 basic Anatomical Positions: Basic Anatomical Position (BAP), Prone, Supine, Trendelenburg, Fowler's

Basic Anatomical Position (BAP)- the body standing upright, with the feet at shoulder width and parallel, toes forward. The upper limbs are held out to each side, and the palms of the hands face forward. →

• Reduces confusion

• Creates a common point of reference for all who study the human body

• Directional Terms (anterior, posterior) are used when the body is in an anatomical position

Prone- A face-down orientation (lying on your stomach) →

• often used for neck and spinal surgeries.

Supine- A face-up orientation “you’re on your spine” (lying on your back) →

Trendelenburg- table or bed is tilted so the head is lower than the feet. →

• Usually used as an emergency treatment for hypotension or shock

Fowler’s- Sitting Position. 3 different positions each different angle: 30, 45, 90 degrees. →

• Fowler’s- 45 degree angle

• Low Fowler’s- 30 degree angle

• High Fowler’s- 90 degree angle

Directional Terms

Essential for describing the relative locations of different body structures. (one band of tissue as “inferior to” another).

• Anterior (or ventral)- The front or direction toward the front of the body. (The toes are anterior to the foot.)

• Posterior (or dorsal)- The back or direction toward the back of the body. (The popliteus is posterior to the patella.)

• Superior (or cranial)- A position above or higher than another part of the body proper. (The arm is superior to the leg).

• Inferior (or caudal)- A position below or lower than another part of the body proper; near or toward the tail. (The pelvis is inferior to the abdomen.)

• Lateral- The side or direction toward the side of the body. (little toe is on the lateral side of the foot)

• Medial- The middle or direction toward the middle of the body. (big toe is on the medial side of the foot)

• Proximal- A position in a limb that is nearer to the point of attachment or the trunk of the body. (proximal end of femur joins with pelvic bone)

• Distal- A position in a limb that is farther from the point of attachment or the trunk of the body. (hand is on the distal end of forearm)

• Superficial- describes a position closer to the surface of the body. (The skin is superficial to the bones.)

• Deep- describes a position farther from the surface of the body. (The brain is deep into the skull.)

• Cranial- Describes a position closer/ upper to the head of the body. (toward the head)

• Caudal- Describes a position closer/ lower to the end of the tail. (toward the tail)

  • Craniocaudal- From head to tail

Superior---Inferior, Anterior----Posterior, Medial---Lateral, Proximal---Distal, Superficial--Deep,

Cranial--- Caudal

Body Planes

Imaginary two-dimensional surface that passes through the body. Consists of 3 planes:

Sagittal (median), Coronal (frontal), Transverse (horizontal)

Sagittal (Median)- The median plane is a vertical plane that divides the body into Right and Left halves. (If the body is divided into EQUAL right & left sides, then it would be known as the midsagittal plane).

Coronal (Frontal)- The frontal plane is at a right angle to the sagittal plane that divides the body into Anterior and Posterior halves

Transverse (Horizontal)- The horizontal plane is perpendicular to the sagittal and coronal planes that divide the body into Superior and Inferior halves

Body Cavities

The body maintains its internal organization utilizing membranes, sheaths, and other structures that separate compartments. The Dorsal (posterior) cavity and the Ventral (anterior) cavity are the largest body compartments. These cavities contain and protect delicate internal organs, and the ventral cavity allows for significant changes in the size and shape of the organs as they perform their functions.

Dorsal (Posterior/ Back) Cavity

Consists of the Cranial and Spinal Cavities.

• Cranial Cavity- Which consists of the Brain

• Spinal Cavity- Which contains the Spinal Cord

The brain and spinal cord are protected by the bones of the skull and vertebral column and by cerebrospinal fluid, a colorless fluid produced by the brain, which cushions the brain and spinal cord within the posterior (dorsal) cavity.

Ventral (Anterior/ Front) Cavity

Consists of two main subdivisions: the Thoracic cavity and the Abdominopelvic cavity.

The Ventral Cavity is protected by the Serous Membrane.

• Thoracic Cavity- A superior subdivision of the anterior cavity, and it is enclosed by the rib cage.

  • Contains the Lungs and Heart, located in the Mediastinum.

  • The lungs contain the major of the respiratory system (bronchi, bronchioles, alveoli, trachea)

  • and the esophagus and thymus

The diaphragm forms the floor of the thoracic cavity and separates it from the inferior Abdominopelvic Cavity.

• Abdominopelvic Cavity- The largest cavity in the body. No physical membrane to divide the cavity but consists of the Abdominal and Pelvic Cavities

1. Abdominal Cavity- The division that houses the digestive organs. (stomach, liver, gallbladder, pancreas, spleen, large and small intestine, appendix)

2. Pelvic Cavity- The division that houses the organs of reproduction. (urinary bladder, reproductive organs, rectum)

   

Abdominal Regions and Quadrants

To promote clear communication, healthcare providers typically divide up the cavity into either nine regions or four quadrants.

Abdominopelvic Quadrants

4 subdivisions of the abdomen, the navel (belly button) is the landmark.

The terms “left/right” and “upper/lower” are always from the perspective of BAP, not your perspective, the patient’s.

• Right Upper Quadrant- Liver, stomach, gallbladder, duodenum, right kidney, pancreas, and the right adrenal gland.

• Right Lower Quadrant- appendix, reproductive organs, right ureter.

• Left Upper Quadrant- Liver, stomach, pancreas, left kidney, spleen, and the left adrenal gland.

• Left Lower Quadrant- left ureter, reproductive organs

*All four quadrants contain portions of the small and large intestines.

Abdominopelvic Regions

The more detailed regional approach

Consists of 9 regions

• Hypochondriac Regions (Left and Right)- the prefix “hypo” means below or under. The word “chondriac” means cartilage, which refers to the cartilage of the ribs.

• Lumbar Regions (Left and Right)- The word “lumbar” refers to the vertebrae in your lower back.

• Iliac Region (Left and Right)- The top of the hip bone has what is called the iliac crest.

The middle column-named after their location relative to the stomach.

• Epigastric Region- The prefix “epi” means above, or over, and “gastric” means stomach or belly.

• Umbilical Region- This is easy to remember because the umbilical region contains your navel, which is also called the umbilicus.

• Hypogastric Region- Hypo = “below,” and “gastric” refers to the stomach or belly.

Module 4 - Skeletal System

The skeletal system is the body system composed of bones and cartilage and performs the following critical functions for the human body

Skeletal System

The skeleton is subdivided into 2 major divisions: Axial and Appendicular

Functions:

• Provides Support- Without the skeletal system you would be a limp mass of organs, muscle, and skin

• Protection for the Organs- From internal injury by covering or surrounding them

• Muscle Attachments- Some support the muscles, others transmit the forces produced when your muscles contract

• Blood cell Formation- In the middle, there is Bone marrow. 2 types of bone marrow: Yellow and Red. Red marrow is where Hematopoiesis (production of blood cells) takes place.

• Fat and Mineral Storage- Acts as a reservoir for a number of minerals important to the functioning of the body (calcium, and phosphorus)

Human Skeletal System Consists of:

Joints- Where 2 bones come together

Cartilage- Hyaline, Elastic, Fibro

Ligaments- Connects bone to bone

Bones: Anatomy

Babies are born with (270-300) bones at birth. These bones eventually fuse to form the 206 Bones Adults have.

Anatomy of Long Bones:

Anatomy of a bone as 2 parts: Diaphysis and Epiphysis

Diaphysis (shaft)- Hollow cylinder of hard compact bone (defense bone)

• In the hollow region of the Diaphysis (or the inside) is where the Medullary Cavity is.

• Medullary Cavity (Canal)- filled with yellow marrow

• Endosteum- delicate membranous lining in the Medullary Cavity in which bone growth, repair and remodeling occur

Epiphysis (end of the bones)- the wider section at each end of the bone. where less strength is needed in the bone.

• In the inside red bone marrow fills the inside in which is where Erythrocytes (red blood cells) are made

Periosteum- fibrous membrane covering the surface of the bone. Contains blood vessels, nerves, and lymphatic vessels that nourish compact bone. (only covers till the end of the Diaphysis not the Epiphysis)

Articular Cartilage- thin layer of cartilage that reduces friction and acts as a shock absorber (only to the ends of the Epiphysis)

Bones: Formation

3 types of cells are found within the bone tissue: Osteoblasts, Osteocytes, Osteoclasts, (and Osteogenic cells. They develop into osteoblasts).

Ossification- Occurring by the 7-8th week of embryonic life, the process of Bone Development, from cartilage to bone. 2 pathways: Intramembranous, Endochondral but bone is the same regardless of pathway.

Fontanel (Soft Spot)- space between bones of the skull from birth to 1 year of age. eventually hardens through ossification

Throughout fetal development and into childhood growth and development bone forms on the cartilaginous matrix. By the time a fetus is born most of the cartilage has been replaced with bone.

Beginning, specialized cells with become osteogenic cells and then to Osteoblasts, they will cluster then spread out by the formation of bone tissue

Osteoblasts- bone cells responsible for forming new bones. Synthesize and secrete the collagen matrix and calcium salts.

• As the secreted matrix surrounding the osteoblast hardens, the osteoblast becomes trapped, changing in structure and becomes an Osteocyte

• Bones increase in circumference by addition of more bone to the outside surface of the diaphysis (shaft).

• As diameter increases, bone material is dissolved from the central part of the diaphysis (shaft).

• This creates an internal cavity called the marrow cavity (medullary canal).

Osteocytes- the primary cell of mature bone and the most common type of bone cell. Maintain the mineral concentration of the matrix via the secretion of enzymes

• Formed when osteoblasts become embedded in the matrix it has secreted.

Osteoclasts- cells responsible for bone resorption, or breakdown.

• They continually breaking down old bone while osteoblasts are continually forming new bone

• Usually found on bone surfaces and at sites of old, injured or unneeded bone

Types of Bones

The 206 bones that compose the adult skeleton are divided into 5 categories based on their Shapes. Each shape of the bone has a distinct function. This includes: Long, Short, Flat, Irregular, Sesamoid

Long Bones- Longer than they are wide, most of the bones of the limb are this type (not including the wrist or ankle),

• even if the bone is short if it is longer than its wide it’s considered a “long bone”

• Found in the arms (humerus, ulna, radius) and legs (femur, tibia, fibula) as well as in the fingers and toes

• Long bones Function as “Levers” they move when muscles contract

Short Bones- Cube-shaped, including tarsals, carpals, cuneiforms

• Approximately equal in length, width, and thickness

• Function to provide stability and support as well as some limited motion

Flat Bones- Flat, thin bones, including sternum, ribs, scapula, and some cranial bones

• Typically thin, it is also often curved

• Function is to serve as points of attachment for muscles and often protect internal organs

Irregular Bones- Weird shaped, that doesn't have an easily characterized shape (does not fit any other classification). Including vertebrae, facial bones, talus

• Vertebrae that support the spinal cord and protect it from compressive forces

• These bones tend to have more complex shapes

Sesamoid Bones- Small round bones, embedded in a tendon, including patella, pisiform, or small bones within the first and second metacarpal and the first metatarsal

• These bones form in tendons (the sheaths of tissue that connect bones to muscles) where a great deal of pressure is generated in a joint

• Function to protect tendons by helping them overcome compressive forces

Axial Skeleton

Forms the Vertical, central axis of the body and includes all bones of the Skull, Spinal column, Ribs, Sternum (Breastbone), Hyoid bone

Consists of 80 out of the 206 bones (Skull, Vertebral Column, and the Thoracic Cage)

Functions:

• Serves to protect the brain, spinal cord, heart, and lungs

• Serves as the attachment site for muscles that move the head, neck, back, and muscles that act across the shoulder and hip joints to move

The Skull (Cranium)

Formed by 22 Bones (8 Cranial Bones and 14 Facial Bones).

Suture- an imobile joint between adjacent bones of the skull (what holds the bones together)

Functions:

• To protect the brain from accidents or fights

• Protect the major sense organs (eyes, nose, ears)

• Provide attachment sites for the muscle

Bones of the Cranium:

Frontal- the single bone that forms the forehead.

Parietal- the base of the skull (Top), roof and sides of skull

Temporal- Side of our face (barley above the ears), houses the ears

Occipital- base of the skull (backend of the skull)

Nasal- Bridge of nose

Vomer- Lower part of nasal septum

Maxilla- Upper jaw

Mandible- Lower jaw, The only Moveable joint in the face

Zygomatic arch- Cheekbone area

Hyoid- U shaped bone in neck

Facial Bones- guard and support eyes, ears, nose, mouth

The Vertebral Column (Spinal Column/ Spine)

Consists of a sequence of vertebrae each of which is separated and united by an Intervertebral Disc

Intervertebral Disc.- separate and unite each vertebrae, together, vertebrae and intervertebral discs form the vertebral column.

• Act as a shock absorber/cushion.

• Throughout our lifetime the discs become thinner - which is why you get shorter with age.

Foramen- Holes in vertebrae that allow for the passage of spinal cord

• Encloses spinal cord

Functions:

• Strong, Flexible column that supports the head, neck, and body and allows for their movement

• Protects the spinal cord, which passes down the back through openings in the vertebrae

Regions:

Sub divided into 3 regions. Cervical, Thoracic, Lumbar

Cervical Vertebrae- (7) has a small body, which carry the least amount of body weight

• 1st Cervical (Atlas)- supports the skull on top of the vertebral column. Does Not have a body or spinous process. Ring shaped. Allows us to nod our heads and articulates with the occipital bone of the skull

• 2nd Cervical (Axis)- serves as the axis for rotation when turning the head toward the right or left.

Thoracic Vertebrae- (12) Located in the chest area. Articulate with the ribs

Lumbar Vertebrae- (5) located in the low back. Large vertebral bodies that bear most of the body's weight

Others:

Sacral vertebrae- Wedge shaped bone formed by 5 fused bones

Coccyx- “Tailbone” formed by 4 fused bones

Ribs and Sternum

The rib cage forms the chest portion of the body. The ribs consist of 12 Ribs along with their costal cartilages and Sternum

Function- The Rib Cage protects the heart and lungs

Sternum

The elongated bony structure that anchors the anterior rib cage. Also known as the Breastbone.

Consists of 3 parts: Manubrium, Body, Xiphoid Process

Manubrium- the wider, upper portion of the sternum, has a shallow U shaped border

• Can be felt at the anterior base of the neck between the medial ends of the clavicles

Body- Central (middle) portion of the sternum. Ribs 3-7 attach to the body

Xiphoid Process- small inferior (lowest) tip of the sternum.

Ribs

Curved, flattened bone that contributes to the wall of the rib cage. There are 12 pairs of ribs

True ribs- (1-7) pairs of costal cartilages join 7 pairs of ribs directly to the sternum

False ribs- (8-10) their costal cartilages are attached to the 7th rib instead of directly to the sternum

Floating ribs- (11-12) connected either costal cartilage nor the sternum

Hyoid Bone- does not attach to any other bone

Appendicular Skeleton

Consists of the Shoulder girdle,

Module 5 - Muscular System

The Muscular system comprises nearly half of our weight, with over 650 muscles

Types of Muscles

There are types of muscles found in the body: Skeletal, Smooth, Cardiac (Sphincter)

Each muscle is made of hundreds or thousands of Muscle fibers (Muscle cells)

Skeletal Muscle- the major muscle group of the body (biceps, quadriceps). Skeletal muscle allows us to perform motor activities, protects internal organs by serving as an extra barrier layer, protects the skeleton by stabilizing it and preventing structural damage to the skeleton

• Skeletal muscle is VOLUNTARY, it can be moved by will

• Skeletal muscle is STRIATED, which means it contains a Striped look. This allows force and contraction

• Skeletal muscle often runs across a joint and Connects to bones via TENDONS

Smooth Muscle- Found in the walls of organs (intestines, stomach, bladder, esophagus). Cells of the Smooth muscle are spindle-shaped and are much shorter than Skeletal muscles.

• Smooth muscle is INVOLUNTARY, it moves unconsciously, contractions are rhythmic and slow

• Smooth muscle is NOT STRIATED

• Smooth muscle Contracts the uterus during labor, Controls diameter of blood vessels as blood circulates through the body

Cardiac Muscle- Only found in the heart. Cardiac muscle fibers are extensively branched and connected with each other at their ends with Intercalated Discs. Conductivity of this allows for transmissions of electrical signals in a wave like pattern so the heart works as a pump when it contracts (when one contracts, all contracts)

• Cardiac muscle is INVOLUNTARY

• Cardiac muscle is STRIATED, BRANCHED

• Cardiac muscle is meant to Contract the heart

Intercalated Disks- connect the ends of the cardiac muscle

• Allows the transmission of electrical signals (like a wave pattern) so the heart works as a pump when it contracts

Sphincter Muscle- (Dilator Muscle) special circular muscles located in the Digestive system (anus, opening between esophagus and stomach, small intestines) and Urinary system (bladder)

• Open and close to control the passage of substances (Both Voluntary and Involuntary)

• Sphincter muscle is STRIATED

Connective Tissues

Tendons- Dense bands that connect skeletal muscle to the bone.

Fascia- Fibrous connective tissue (primarily collagen) sheets that Wrap around muscle bundles to hold them in place.

• attaches, stabilizes, encloses, and separates muscles and other internal organs

Characteristics of Muscles

These include Contractibility, Excitability, Extensibility, Elasticity

Contractility: Quality that no other tissue possesses

Skeletal: Contraction of skeletal muscle causes movement of the bones. Muscles become SHORTER and THICKER

Cardiac: Contraction of cardiac muscle makes the heart pump blood to the entire body

Smooth: Contraction of smooth muscle it surrounds blood vessels, intestines, and numerous other organs which causes the diameter of these tubs to increase and decrease

Excitability or Irritability- Ability to respond to certain stimuli (the production of action potentials)

• Characteristic of both muscle and nervous cells (neurons)

Extensibility- Ability to be Stretched. Muscles on the back are either extended or stretched

Elasticity- Ability to return to its original state when relaxing (like a rubber band)

Muscle Tone- Partial contraction. Muscles should always be slightly contracted and ready to pull. Maintained with proper nutrition and regular exercise

Atrophy- Muscles become weak and flaccid, from lack of movement. Waiting away of muscle

Hypertrophy- Muscles become enlarged, from over exercise of muscles. Overgrowth

Muscle Fatigue- inability to generate force. Caused by Accumulation of Lactic Acid in the muscles, can lead to fatigue and cramps

• Accumulation of lactic Acid, if from long periods of exercise where blood is unable to transport enough oxygen for the complete oxidation of glucose in the muscles, which causes muscles to contract Anaerobically (without oxygen)

• Symptoms: Muscle weakness, soreness, localized pain, shortness of breath, muscle twitching, trembling, weak grip.

• Treatment: Stop, Rest, and Take enough oxygen. This changes lactic acid back into glucose for muscle cells

Naming Muscles

Muscles can be classified and named by: Shape, Size compared to other muscles in the area, location in the body or location of its attachments to the skeleton, how many origins it has, its action

*Study Quizlet Terms

Muscles of the Body

Head and Neck Muscles

Frontalis- Moves eyebrows up and wrinkles forehead

Masseter- chewing muscle of the jaw

Orbicularis Oculi- closes the eyelids

Orbicularis Oris- encircles the mouth

Temporalis- chewing muscle of the upper jaw that covers the temporal bone

Zygomatic Major- smiling muscle

Sternocledidomastoid- rotates the head and flexes the neck

Torso/Trunk (Anterior/ Front)

External Intercostals- Between the ribs. Assists the lungs by raising the ribcage

Diaphragm- thin, dome shaped muscle that separates the thoracic and abdominal cavity. Contracts/relaxes when you inhale

Rectus Abdominis- the “six pack”, help bend your abdomen

External Oblique- located on each side of the rectus abdominis. Twists the trunk

Internal Oblique- located on each side of the rectus abdominis below the external obliques. Assists with twisting the trunk and respiration

Torso/Trunk (Posterior/ Back)

Latissimus Dorsi- “butterfly wings” lower back muscle, known as the largest muscle in the body

Upper Extremities:

Trapezius- upper back, supports the arm and helps with scapula

Deltoid- helps lift the upper arm, one of the sites for injections

Pectoralis Major- chest muscles, assist with arm movements and motion

Biceps Brachii- lifts the forearm. On the anterior of the upper arm

Triceps Brachii- posterior arm. Straightens the arm

Brachioradialis- flexes the forearm. Pronation and supination

Lower Extremities

Gluteus Medius- sits on the outer surface of the ilium, helps with hip movement

Gluteus Maximus- butt, helps with several hip movements

Rectus Femoris- long, thin muscles on the femur, part of the quads

Vastus Lateralis- side of the thigh, helps extend the knee and move leg forward

Sartorius- longest muscle in the body, runs from hip to to the medial knee

Gastrocnemius- calf muscle, works with the soleus

Soleus- under the gastrocnemius. Runs from the knee to the heel. Helps with standing and walking

Tibialis Anterior- on the front of the tibia. Dorsiflexes and inverts the foot

Functions of the Muscular System

Movement, Posture, Body Heat, Protection of internal organs

Movement: of the digestive system by contractions, Circulatory system and its regulation of the heart beats

Body Heat: Homeostasis (shiver, sweat, exercise. Basically the body adjusting to the environment automatically)

Disorders

Fibromyalgia- Disorder characterized by widespread musculoskeletal pain accompanied by fatigue, sleep, memory and mood issues.

Causes- Unknown, a variety of causes: genetics, infections, psychological or emotional trauma

Symptoms- Widespread pain, fatigue, cognitive difficulties (memory loss), mood swings

Diagnosis- diagnosis can be made if a patient has widespread pain for more than 3 months with no underlying medical condition that would cause pain.

Treatment- No cure. Medication and self carem improve sleep, reduce stress to lessen symptoms

Hernia- Occurs when an organ protrudes through an opening in a weak muscle.

Causes- muscle weakness and strain

Locations: 3 locations of a hernia

Abdominal hernia- Occurs when organs protrude through the abdominal wall.

Inguinal hernia- Occurs in the inguinal area.

Hiatal hernia- When stomach pushes through the diaphragm

Symptoms- pain or discomfort in affected area, especially when bending over coughing or lifting

Diagnosis- physical exam, endoscopy, barium x-ray

Treatment- surgery, lifestyle changes, medication

Muscle Spasms- A “cramp” or sustained contraction of a muscle

Causes- Overuse/overuse, Compression of nerves, Dehydration, Low levels of electrolytes (i.e. magnesium, potassium, calcium), Not enough blood to muscles, Pregnancy, Certain medications

Locations- can happen anywhere but most commonly: thighs, feet, hands, arms, abdomen, and along rib cage

Module 7 - Digestive System

Break down the foods we eat, release their nutrients, and absorb those nutrients into the body. Divided into 2 groups that contain different organs systems: Alimentary canal, Accessory digestive organs.

The Digestive System

Uses both Mechanical and Chemical activities to break down food into absorbable substances.

Digestion Process:

This process of digestion includes 6 Steps: Ingestion, Propulsion, Mechanical/Physical digestion, Chemical digestion, Absorption, Defecation

Ingestion- 1st step. Entry of food into the Alimentary Canal through the mouth, the food is chewed and mixed with saliva (contains Enzymes that break down carbohydrates plus some lipid [fat] digestion via lingual lipase), chewing increases the surface area of the food into what is now called a Bolus.

Bolus- A mixture of food and saliva, once its soft and pliable

Propulsion- 2nd step. Refers to the movement of food through the digestive tract. Includes both voluntary (swallowing) and involuntary (process of peristalsis) processes

Peristalsis- consists of sequential, alternating waves of contraction and relaxation of alimentary wall smooth muscles that help propel food through the digestive tract.

• These waves mix food with digestive juices.

• Very powerful that you can swallow, even if your standing on your head

Mechanical Digestion- (part of steps) a physical process that does not change the chemical nature of the food. Instead makes the food smaller to increase both surface area and mobility

Mastication- “Chewing” as well as tongue movements that help break down food, mixing saliva with the food

Churning- stomach breaking down food to expose it to more digestive juices

Segmentation- occurs in the small intestine, contractions of circular muscle of the muscularis layer to continuously divide, break up and mixing the contents further with digestive juices

Chemical Digestion- digestive secretions break down complex food molecules into their chemical building blocks (proteins to amino acids). Secretions contain water, various enzymes, acids, and salts. Completed in the small intestine

Absorption- 3rd step. Primarily in the small intestine, food that has been broken down is of no value to the body unless it enters the bloodstream and its nutrients are absorbed.

Defecation- 4th step. Undigested materials are removed from the body as Feces.

*Steps in the ACTUAL NOTES: Physical, Chemical, Absorption, Elimination.

Alimentary Canal

Also called the gastrointestinal (GI) tract or Gut. A One Way tube, from Mouth to Anus

Function- the organs of the alimentary canal is to nourish the body

Contains: Mouth (buccal cavity), Pharynx (throat), Esophagus, Stomach, Small intestines, Large intestines

Mouth (Buccal Cavity)

The Mechanical Portion of digestion that occurs in the mouth, involving the Teeth, tearing and crushing the food into smaller pieces and the Tongue smashing it against the hard Palate of the mouth.

• Reduces the size of the food particles and increase the surface area available to interact with the mouths chemical agents (saliva)

Consists: Tongue, Teeth, Salivary Glands, Palate, Uvula

Tongue

Accessory Structures

The accessory organs aid in the breakdown of food.

Module 9 - Nervous System

The Nervous system is Divided into 2 divisions: Central nervous system (CNS), Peripheral nervous system (PNS)

The nervous system communicates with various nerve cells (neurons) activated by action potentials (stimulus) either my motion, or senses that go through the body.

Central Nervous System (CNS) Anatomy

Includes the Brain and the Spinal cord. A person's conscious experiences are based on neural activity in the brain aswell as the regulation of homeostasis (by a specific region in the brain) in the Brain. While, coordination of reflexes depend on the integration of sensory and motor pathways in the Spinal cord.

The Brain

The adult brain is described in terms of 4 Major Regions: Cerebrum, Diencephalon, Brain stem, Cerebellum.

Weighs 3 lbs; contains 100+ billion neurons, brain tissue dies in 4-6 min without adequate oxygen

The Cerebrum

Takes up most mass of the brain. (largest part of the brain).

Comprises of the Outer Grey matter (Cerebral Cortex) and White matter

The cerebrum is divided into 2 Hemispheres: Lef and Right Hemispheres. This is separated by the Longitudinal Fissure.

Longitudinal Fissure- separates the cerebrum into 2 hemispheres (Cerebral hemispheres)

Corpus Callosum- provides the major pathway for communication between the 2 hemispheres of the cerebral cortex (not mentioned in the notes)

Separated into 4 Major regions: Temporal lobe, Parietal lobe, Frontal lobe, Occipital lobe

Temporal lobe- primary auditory sensation (part of the limbic system), memory function is associated with this lobe (face recognition)

• Responsible for establishing long term memory

• Can recall sensations of smell, movement, sensory feedback

Parietal lobe- All of the tactile senses are processed in this area: touch, pressure, tickle, pain, itch, vibration (general senses of the body) senses are processed here.

Frontal Lobe- primarily associated with motor functions. Aswell as thinking of a movement to be made, production of language or controlling movements responsible for speech, cognitive function of the basis of personality, short term memory, and consciousness.

• motor neurons that instruct cells of the spinal cord to move skeletal muscles

Occipital Lobe- responsible for primary visual perception. Visual info is processed in the temporal and parietal lobes.

The Cerebral Cortex

A continuous outer layer of gray matter, thin extensive region of wrinkled matter that covers the cerebrum

Gyrus- the ridge of one of the wrinkles (plural= gyri)

Sulcus- the groove between 2 gyri

The Diencephalon

The connection between the cerebrum and the rest of the nervous system. The rest of the brian, spinal cord, PNS all send info to the cerebrum through the diencephalon.

Located between the cerebrum and the midbrain

The diencephalon contains 2 Major regions: Thalamus, Hypothalamus

Thalamus

Relay station for incoming & outgoing nerve impulses from the various sense organs of the body (with exception of olfactory sensations).

All sensory info (except smell) passes through the thalamus before processing by the cortex for interpretation

• Takes in information (sensory, synapse, motor neurons) processes, filters, and relays that information to the appropriate regions of the cerebral cortex.

Like a “double checker” before passing it to the cerebral cortex for actual processing.

Hypothalamus

Collection of nuclei that is largely involved in Regulating homeostasis.

The executive region in charge of the Autonomic nervous system and the endocrine system through regulation of the anterior pituitary gland.

• Other parts of the hypothalamus are involved with memory and emotion as part of the Limbic system

Below the thalamus

Limbic System- collection of structure involved in emotion, memory, and behavior

Consists of 9 Vital functions:

• Autonomic nervous control (sympathetic & parasympathetic)

• Cardiovascular control (controls BP, heart beat, blood vessel dilation & constriction….)

• Temperature control (98.6 degrees Fahrenheit)

  

• Appetite control (hunger pangs & satiety center)

• Water balance (thirsty = body needs more water)

• Manufacture of oxytocin (uterus contraction during labor)

• Gastrointestinal control (increases peristalsis & secretion from intestinal glands)

• Emotional state (controls display of emotions)

• Sleep control (sleep-wake cycle)

The Brain Stem

Controls the flow of messages between the brain and the body.

Consists of 3 regions: Midbrain, Pons, Medulla

Midbrain- coordinates sensory representations of the visual, auditory, and somatosensory perceptual spaces

Pons- main connection with the cerebellum. Assist with the Medulla to regulate functions

Medulla- regulate crucial functions: cardiovascular and respiratory systems and rates (works with the Pons)

* Damage to the Brain Stem inflicts a Coma.

The Cerebellum

“Little brain” Responsible for comparing information from the cerebrum with sensory feedback from the periphery through the spinal cord

Composed of 2 hemispheres.

Controls all body functions related to skeletal muscles, including: Balance, Muscle tone, Muscle movement

Protective Coverings of the Brain and Spinal Cord

The outer surface of the CNS is covered by a series of membranes composed of connective tissues called Meaninges

Meninges- protect the brain and line the skull and vertebral canal and protect the brain and spinal cord

Consists of 3 Membranes: Dura mater, Arachnoid mater, Pia mater

Dura Mater- Outermost thick fibrous layer and a strong protective sheath over the entire brain and spinal cord. Accorded to the inner surface of the cranium and vertebral cavity

Arachnoid Mater- Middle membrane of thin fibrous tissue that forms a loose sac around the CNS. Resembles a spider web

Pia Mater- Delicate innermost thin fibrous membrane that follows the convolutions of gyri and sulci in the cerebral cortex and fits into other grooves and indentations.

Subarachnoid space- between arachnoid and pia mater, filled with cerebrospinal fluid

Cerebrospinal Fluid- acts as a liquid shock absorber and source of nutrients for the brain

Neurons

Considered to be the basis of nervous tissue. Can send messages (action potentials).

Are responsible for the electrical signals that communicate information about sensations and that produce movements in response to those stimuli, along with inducing thought processes within the brain.

Parts of the Neuron:

Main Parts:

Soma (cell body)- contains the nucleus and most of the major organelles

Axon- A fiber that merges from the cell body and projects to target cells. Cane branch repeatedly to communicate with many target cells. Propagates the nerve impulse.

Dendrites- small finger-like branches (from the hand). They receive information from other neurons at specialized areas of contact called synapses

Synapses- Space separating two neurons where the impulse jumps to the next neuron.

Other parts that connect to other parts of the neuron:

Myelin- Made of glial cells, acts as an insulator that wraps around the axon that has gaps along the fiber, which speeds up the process of communication of each neuron. Those gaps are called “Node of ranvier”

Node of Ranvier- an important way that electrical signals travel down the axon

Schwann Cell- 2nd type of glial cell. Insulates axons with myelin and periphery. Wraps around a portion of only 1 axon segment.

Process of Synapse Exchange: (simple terms: its a chemical change)

Action potential (message from neurons) flows down, calcium flows into nerve, neurotransmitters (GABA, hormones) get released and move across the synapse, match with an ion channel and gets shape change, the action potential moves in reverse

*The neurotransmitter between muscle cells & the nervous system is Acetylcholine.

*In order for a nerve impulse to begin, it must be initiated by a stimulus.

Types of Neurons:

Sensory Neuron- send information from sensory receptors (i.e. skin, eyes, ears, nose, tongue) to the spinal cord and brain.

Motor Neuron- send information from the central nervous system back to the body. Responsible for causing muscle fibers to contract

Associative (interneurons)- send information between sensory and motor neurons.

The Spinal Cord

Maintains the tube structure and is only specialized into certain regions.

• Begins at foramen magnum.

• Continues down to 2nd lumbar vertebrae.

• White and soft in the spinal canal.

• Surrounded by cerebrospinal fluid.

• Functions as a reflex center and a conduction pathway to and from the brain.

Divisions of the Nervous System

Peripheral Nervous System (PNS)

Defined as everything that is not the CNS. Basically the spinal nerves and other nerves of the body.

Provides a complete network of motor and sensory fibers connecting the CNS with the rest of the body.

Includes 12 pairs of Cranial nerves and 31 pairs of Spinal nerves.

Cranial nerves: Spinal nerves:

Olfactory = smell

Optic = vision, eyesight

Oculomotor = movement of eye muscle

Trochlear = movement of eye muscle

Trigeminal = face & teeth muscles, chewing

Abducens = movement of eye muscle

Facial = facial expressions, taste

Vestibulocochlear = hearing & balance

Glossopharyngeal = movement of throat muscle, taste

Vagus = movement of throat, affects heart, digestive system

Accessory = movement of neck muscles

Hypoglossal = movement of tongue

Divided into 2 Divisions: Somatic and Autonomic Nervous Systems

Somatic Nervous System

Module 10 - Sensory System

The Central Nervous System (CNS), which consists of the brain and spinal cord collect information from the senses and spread the information throughout the body. We have senses to collect information from our surroundings and send the info to our brains to react.

The body has 5 senses: Vision, Hearing, Smell, Touch, Taste

Eyes (Vision)

Vision is the special sense of sight that is based on the transduction of light stimuli received through the eyes.

External Structure of the Eyes:

The Orbital Cavity- cone-shaped cavity formed by the skull that houses & protects the eyeball. (contains all listed below)

Eyelids (with Lashes)- help to protect the eye from abrasions by blocking particles that may land on the surface of the eye.

Conjunctiva- Thin membrane that extends over the white areas of the eye (the sclera), connecting the eyelids to the eyeball

Lacrimal Apparatus- the entire tear system which includes: Lacrimal duct, Lacrimal gland

Lacrimal Duct- Tears produced by the gland flow through the lacrimal duct to the medial corner of the eye, where the tears flow over the conjunctiva, washing away foreign particles. Why water also comes out of nose

Lacrimal Gland- what produces tears. located just inside the orbit, superior and lateral to the eyeball

Layers of The Eyes

There are 3 layers of the eye: Sclera, Choroid, Retina

Sclera- Tough, outer layer; “white of the eye;” helps maintain shape of the eye. Extrinsic muscles are attached to the sclera and help move the eyeball

Choroid- The middle layer of highly vascularized connective tissue that provides a blood supply to the eyeball (nourishes outer layers of the retina).

Retina (neural tunic)- the innermost layer, which contains the nervous tissue responsible for photoreception (light rays reflect here to form an image). contains rods and cones. And Optic Disc.

Rods- sensitive to dim light.

Cones- sensitive to bright light and color

Optic Disc - on retina (back end); known as blind spot, nerve fibers form optic nerve here.

Internal Structure of The Eye

Cornea → Pupil → Lens → Retina → Rods & Cones → Optic Nerve → Brain (Passageway of light to brain)

Cornea- “window of the eye” transparent and permits the passage of light rays.

Pupil- the hole at the center of the eye that allows light to enter.

Iris- the colored part of the eye. is a smooth muscle that opens or closes the pupil. Contains intrinsic muscles within the iris that control the size of the pupil and amount of light entering the eye

Lens- Crystalline structure located behind the iris and pupil; separates anterior and posterior chambers; focuses images on the retina.

Optic Nerve- carries the impulses formed by the retina to the brain for interpretation.

Brain- The optic lobe of the brain and then process the signals and construct the images we see.

The eye is also divided into two cavities: the Anterior cavity and the Posterior cavity.

The anterior cavity is the space between the cornea and lens, including the iris and ciliary body. It is filled with a watery fluid called the aqueous humor

The posterior cavity is the space behind the lens that extends to the posterior side of the interior eyeball, where the retina is located. The posterior cavity is filled with a more viscous fluid called the vitreous humor.

Aqueous humor- Anterior chamber filled with watery fluid called aqueous humor that nourishes the lens and maintains pressure in the eye..

Vitreous humor- jelly-like fluid that maintains eye shape and refracts light rays.

These 2 help:

• Maintain the eyeball’s spherical shape

  

• Refraction (bending) light rays as they pass through the eye.

Ear (Hearing)

Transduction of sound waves into a neural signal that is made possible by the structures of the ear

Consist of the: Outer, Middle, and Inner divisions

Pinna → External auditory canal → tympanic

membrane → ossicles (malleus, incus, stapes) →

cochlea → auditory nerve → brain

The Outer Ear

Also known as the External ear. Consists of the: Auricle, Auditory, Tympanic membrane

Auricle (Pinna)- the visible portion of the ear. The C-shaped curves of the auricle direct sound waves toward the auditory canal. The canal enters the skull through the external auditory

Auditory- Lined with glands that secrete a wax-like substance called cerumen that protects the ear. The canal leads to the tympanic membrane.

Tympanic Membrane- or ear drum, which vibrates after it is struck by sound waves.

Middle Ear

Consists of a space spanned by 3 small bones called the Ossicles. The three ossicles are the Malleus, Incus, and Stapes.

Connected to the pharynx through the Eustachian tube, which helps equilibrate air pressure across the tympanic membrane.

Malleus (Hammer)- attached to the tympanic membrane and articulates with the incus.

Incus (Anvil)- articulates with the stapes

Stapes (Stirrup)- attached to the inner ear, where the sound waves will be transduced into a neural signal

Eustachian Tube- equalizes the air pressure in the middle ear with the outside atmosphere.

Inner Ear

often described as a bony labyrinth, as it is composed of a series of canals embedded within the temporal bone.

Contains the: Cochlea, Cochlear duct, Organ of corti, Semicircular canals

Cochlea- spiral shaped organ of hearing that contains the cochlear duct.

Cochlea duct- the central cavity of the cochlea that contains the sound-transducing neurons. filled with fluid that vibrates when sound waves are transmitted by the stapes.

Organ of corti- which transduce the wave motion of the two scala into neural signals. Contains delicate, hair-like cells inside the cochlear duct, picks up vibrations of fluid and transmits them as a sensory impulse along the auditory nerve to the brain.

Semicircular Canals- three structures in the inner ear that contain liquid set in motion by head and body movements. These impulses are sent back to the cerebellum to maintain balance or equilibrium. (nothing to do with hearing)

Nose (Smelling)

The sense of smell, or olfaction, is also responsive to chemical stimuli. The olfactory receptor neurons are located in a small region within the superior Nasal Cavity

Limbic System- generates our basic emotions such as affection, aggression, fear

Cilia- Small hair-like projections that trap larger dust particles entering the nose.

Nasal septum- partition that divides the nose into right and left sides.

Turbinates- Bones in the nasal cavity that are covered in mucous. Increases surface area of the nasal cavity & helps with filtration of the air breathed in.

Olfactory Bulb- structures located at the bottom of each cerebral hemisphere that process information about odors.

The nose and its structures provide for our sense of smell. Smell accounts for 90% of our sense of taste.

Olfactory Receptors- In the nasal cavity, there is a patch of tissue (about the size of a postage stamp) called the olfactory epithelium, which has a plentiful supply of nerve cells with specialized receptors. These receptors send signals to adjoining olfactory bulbs, an extension of the brain.

• When particles travel through the air and enter your nose, those chemicals come into contact with nerve endings in our nose, those molecules stimulate olfactory receptors that will in turn send information to the *temporal lobe* of the brain (where smells are interpreted)

Tongue (Taste)

The tongue is a mass of muscle tissue. Contains of 4 Tastes- Sweet, Sour, Salty, Bitter

Taste is one of the weakest senses, with only 10,000 taste buds inside our mouths; even on the roofs of our mouths.

Everyone’s tongue print is different (like a fingerprint)

Along with the rest of the oral cavity, it is lined by a stratified squamous epithelium. Along with raised bumps (papilla)

Papila- Bumps on the surface of the tongue that contain the taste buds.

Taste buds- contain specialized gustatory receptor cells for the transduction of taste stimuli.

• Receptors in taste buds send stimuli through 3 cranial nerves to the cerebral cortex for interpretation.

Skin (Touch/ Sensory Receptors)

Stimuli in the environment activate specialized receptor cells (specialized sensory nerves) in the peripheral nervous system (PNS).

The Epidermis, Dermis, and Hypodermis contain specialized sensory receptors (there are multiple kinds)

In addition, these sensory nerves detect: Touch, Surface Temp., Pain

Structural Receptor Type

receptors can be classified based on their location relative to the stimuli. (there are 3 but only talk about Proprioceptors)

Exteroceptor, Interoceptor, Proprioceptor

Proprioceptor- a receptor located near a moving part of the body, such as a muscle, that interprets the positions of the tissues as they move. (found in tendons, muscles, joint capsules)

• without these we wouldn't be able to fundamentally move (feed/ clothing ourselves)

• Detects changes in muscle length and tension

Functional Receptor Types

However the main Receptor cells mentioned are: Mechanoreceptors (Touch), Thermoreceptors (Temp.), Nociceptor (Pain)

Mechanoreceptors (Touch receptors)- Physical stimuli, such as pressure and vibration, as well as the sensation of sound and body position (balance), are interpreted by this receptor.

• Reveals info about things that you actually come in direct contact with

Thermoreceptors (Temperature receptors)- either sensitive to temperatures above (heat) or below (cold) normal body temperature.

• pass this information to the hypothalamus which then triggers changes needed to ensure body temperature remains constant.

Nociceptor (Pain receptors)- pain is primarily a chemical sense that interprets the presence of chemicals from tissue damage, or similar intense stimuli (can also be caused by mechanical, thermal, chemical stimuli)

• Sharp pain = “quickly move away”

• Dull pain = “avoid till healed”

• Over 3 Million pain receptors, found in the skin, muscles, bones, blood vessels, some organs

Disorders

Only the most important parts. Not all symptoms/ treatments

Eyes

Cataracts- condition where the Lens gradually become cloudy

• Common in people greater the 70 Yrs

• Painless, gradually blurring and loss of vision. Pupil from black to milky white

Causes- aging, injury changes the tissue that makes up the lens, genetics

Signs/Symptoms- clouded, blurred, dim vision

Treatment- Surgical removal of the lens and replacing it with artificial lens

Color Blindness- inability to distinguish colors (misty from red, greens, blues)

• Cone cells are affected by this

Causes- genetics, anything that messes with your body

Symptoms- trouble seeing colors and the brightness of colors in the usual way

Treatment- none. Special contact lenses and glasses may help

Conjunctivitis- Pink eye. inflammation of the conjunctiva. Highly contagious

Causes- viruses, bacteria, allergies

Symptoms- redness, pain, swelling, and discharge in one or both eyes

Treatment- antibiotic eye drops, good hygiene

Detached Retina- where the retina pulls away from the layer of blood vessels that provides it with oxygen and nutrients.

• Longer untreated = higher permanent vision loss %

Causes- a hole or tear in the retina allows fluid to pass through & collect underneath the retina, pulling retina away from underlying tissues. Most common is Aging

Symptoms- sudden appearance of of many floaters, blurred vision, reduced peripheral vision

Treatment- surgery

Diabetic Retinopathy- complications of diabetes that affects the eyes

• Can result in blindness blindness

Causes- damage of the blood vessels of the retina

Symptoms- spots/ floaters, blurred vision, dark/ empty areas in vision

Module 12- The Excretory System

Overview of The Excretory System

Excretory System-

The body's way of getting rid of waste that it cannot use. This system does not work alone but gets carried out with other systems like the;

The Respiratory System (gas)- The Integumentary System (sweat)- The Digestive System (solid waste)- and the Urinary System

Functions

• regulation of blood pH, a function shared with the lungs and the buffers in the blood.

• Regulation of blood pressure, shared with the heart and blood vessels.

• eliminates metabolic waste (Things like CO2, extra water, and nitrogenous wastes)

• Regulates blood volume and fluid balance

• helps to maintain homeostasis

The Urinary System

The urinary system is made up of 4 specific organs: The 1. Kidney, 2. Ureters, 3. Urinary Bladder, 4. Urethra

The Kidneys (Renal)- Composition

The kidneys filter the blood as well as produce urine. They are 2 “bean-shaped organs” located in the lower back, just above the pelvis.

• The Convex side (the outer curve part of a bean) faces laterally (away from the origin)

• The Concave side (the inner curve of a bean) faces medially (close to the origin)

• Renal Hilum- is the indent (or the double curve on the concave side of the bean) there are the exit and entry sites for structures of the kidney; renal vessels (the renal vein and artery), as well as the renal nerve and ureter to enter the kidney.

• Renal capsule- Tough fibrous layer surrounding the kidney

Sections of The Kidneys (Inner Structures)

There are 3 regions in the kidney: Renal cortex, Renal medulla, and Renal pelvis.

Renal Cortex- the frontal section through the kidney that reveals an outer region. It is a smooth, outer portion of the kidney that contains blood vessels and collecting ducts.

Renal Medulla- the inner region of the kidney, contains Renal Pyramids, which are cone-shaped tissue that contains Tubules for the transportation of urine and Nephrons.

Renal Pelvis- emerges from the hilum, located above the ureter. It has cup-like calyces that collect urine before sending it to the urinary bladder.

Renal Column- located between renal pyramids. They are extensions of the renal cortex. Support and separate Renal pyramids

Renal Calyces- cup-shaped structures in the kidney that collect and channel urine through

• Can be Minor (small) or Major (large) based on the picture

Nephrons

Both the Medulla and Cortex contain the nephrons.

They are the “functional units” of the kidney; they do the kidney’s job of:

• Cleaning/ filtering the blood,

• Selectively reabsorbs nutrients the body needs into the blood and secretes the ones we don't need or have too much of into the urine.

• To balance the plasma to homeostatic set points

• They do this in 3 principal functions: Filtration, reabsorption, and secretion.

Consists of 2 components, the Tubular Component (Renal Tubule), and the Vascular component (Renal Vasculature)

Tubular Component (Renal Tubule)

This component is responsible for the further filtration of the blood after being filtered by the glomeruli within the Bowman’s capsule. In other words, the second filtration

Consists of:

• Bowman's Capsule- a cup-like shape that forms around the glomerulus, its purpose is to filter blood

• Proximal Convoluted Tubule (PCT)- absorbs all the glucose and amino acids that we need

• Distal Convoluted Tubule (DCT)- determines the amount of reabsorption based on what the body needs. If there are no hormones present, the DCT is impermeable,

• Loop of Henle- has 2 parts, ascending and descending limbs, the major site of salt/ water balance in the body.

• Ascending limb- only salts are absorbed here, part of the loop of Henle

• Descending limb- only water is absorbed here, part of the loop of Henle

• Collecting Tubule- a microscopic tube that carries urine from the nephrons to the renal pelvis and ureters

Vascular Component (Renal Vasculature)

This Component focuses on the filtration and the movement of absorption and secretion of blood filtering

Consists of:

• Renal Artery- the first step in blood filtration, the site where blood enters to be filtered, connected with the kidney, blood enters through this, and the renal artery branches into afferent arterioles

• Afferent Arterioles- branches from the renal artery in the kidney, they carry blood to the filtration site

• Efferent Arterioles- this drives the filtration, making pressure to drive the blood through filtration from pressure, because the efferent is smaller than the afferent arteriole.

• Glomerulus- the area where blood is filtered the most, a simple capillary bed formed by a branching afferent arteriole, filtered here, and everything is forced into the tubular Bowman’s capsule

• Peritubular Capillary Bed- a network of tiny blood vessels in the kidney that filter waste from the blood and reabsorb nutrients, and excrete the useless ones

• Renal Vein- the main blood vessel that carries blood from the kidney and ureter to the heart from the lower part of the body. Each kidney has 1

Ureters

From the renal hilum, the renal pelvis creates a narrow tube, which, being the ureter, its purpose is to transfer urine into the bladder. Each kidney has a ureter that connects to it via the renal pelvis. 10-12” long

Urinary Bladder

From the end of the ureters is the bladder. Where urine is delivered to, called a “dome and hollow”. In females, the bladder is anterior to the uterus, while posterior to the pubic bone and anterior to the rectum during late pregnancy. Since it's meant to hold urine until it's voluntarily let out, the “dome” expands when it's filled with urine.

Has 2 sphincter muscles that control the release of waste: Internal, External

Internal Sphincter- Involuntary, smooth muscle

External Sphincter- Voluntary control

Can hold 400mL (Normal Capacity)

Urethra

The end stage of the urinary system, where urine is transported out of the body for disposal. Vagina for women, penis for men. Connected to the bladder that releases waste.

Urinary meatus

External opening of the urethra to the outside of the body. Where waste comes out of.

The Excretory System (Urinary included) has 3 steps: Filtration, Reabsorption, Secretion. (and Excretion)

Filtration

Parts used- Glomerulus, Renal Artery (Afferent and Efferent Arterioles), Bowman’s capsule.

1. Blood enters the kidney via the Renal Artery and begins filtration at the Glomerulus.

2. The renal artery branches into afferent arterioles that carry the blood to the glomerulus

3. At the glomerulus, blood gets filtered, and everything gets forced into the Bowman's capsule via pressure from the efferent arterioles.

4. Back-up blood is released, which releases the pressure, and then the substances go to the tubule. In there, blood takes back all substances that the body doesn't want excreted as urine; they move from the tubule into the blood. Substances like water, ions, glucose, and amino acids

5. However, substances like electrolytes, drugs, excess vitamins, salts, and sugars are what the body doesn't need, so they are secreted in the urine. They move from the blood to the tubule. This is called Tubular Secretion.

Reabsorption

Parts used: PCT, Loop of Henle (Ascending, Descending limbs), DCT, collecting ducts

• Most water is recovered in the PCT, loop of Henle, DCT, and 10% reaches the collecting ducts

• Reabsorption and secretion are performed before the urine becomes urine

• Reappropriation is taking the “good stuff”

1. First, the PCT will absorb all the glucose and amino acids the body needs

2. While the loop of Henle absorbs water (in the descending limb) and salt (in the ascending limb)

3. The DCT measures how much reabsorption the body needs to do.

• 2 things can happen, it can stop reabsorption or continue (to certain substances)

1. If there are no Hormones present, the DCT becomes impermeable, and nothing else can get through

2. If Hormone *ADH* is present, the DCT becomes permeable to water, which will move into the blood

3. If Hormone *Aldosterone* is present, the DCT becomes permeable to salts, which will move into the blood

Aldosterone- Regulates the balance of water and electrolytes in the body.

• Encouraged the kidney to excrete potassium into the urine and retain sodium, thereby retaining water.

• 1 of 2 Hormones that control urine production

ADH (Antidiuretic hormone)- regulates water balance in the body by controlling how much water is excreted by the kidneys, leading to water retention and potentially higher blood pressure

• 1 of 2 Hormones that control urine production

Secretion

Parts involved: Tubule

• Secretion occurs in the entire length of the tubule.

• Excess materials we don't need or have enough of are moved into the tubule and finally made into urine.

1. The urine makes its way to the bladder via the ureters and into the bladder, where it's stored until it’s released from the body.

Excretion (Not part of the Urine formation)

Process of removing nitrogenous waste material, salts, and excess water from blood.

• If not, toxic waste will build up and cells will suffocate and poison themselves.

Blood Pressure *NOT NEEDED.

The excretory system also monitors blood pressure; if the blood pressure is low, then blood cannot be transported to the Bowman’s capsule.

• The kidneys monitor blood pressure with something called the juxtaglomerular apparatus.

  • If the blood pressure is low or the chlorine ion concentration is low, the Juxtaglomerular gets triggered secretion of an enzyme, “Renin” (maybe needed)

  • When renin mixes with blood, it triggers the release of angiotensin II, which causes Vasoconstriction (blood vessels get smaller), which will make the blood pressure increase.

  • Increased blood pressure stimulates the adrenal cortex to produce aldosterone.

  • This also stimulates the reabsorption of salt, which will make the body reabsorb water and increase blood pressure.

Normal and Abnormal Urine Characteristics

Dilute Urine- Urine that has a higher than average water content.

Diuretics- drugs that increase the passing of urine. (caffeine)

Average urinary output: 1,500 mL per day.

What constitutes an abnormal urinalysis: Color, UTI, Increased levels of protein, Odor

Abnormalities of Urine:

Increased level of protein (small amounts ok)

Sugar: normal levels too low to detect. Any amount of sugar that is detected calls for follow-up testing for diabetes.

Ketones: like diabetes, any ketones in urine could be a sign of diabetes.

Bilirubin: product of RBC breakdown. May indicate liver damage or disease.

Evidence of infection: if leukocytes present in urine, may indicate UTI.

Blood: could be a sign of kidney damage, infection, kidney/bladder stones, kidney or bladder cancer, or blood disorders.

Bacteria/yeasts: infection

Crystals: kidney stones

Infections and Diseases

Urinary Tract Infection (UTI)- infection and inflammation of the urethra and sometimes even the urinary bladder.

• Much more common in women, due to their short urethra and located close to the anus, bacteria that are harmless in the GI tract can cause more problems in the urinary tract.

• Cause pain and burning urination, frequent, urgent urination, cloudy or bloody urine, fever, and weakness

Cystitis- an inflammation of the urinary bladder. Can be caused by fecal bacteria entering the urethra

• Usually brings fever, frequency, urgent, burning urination, bacteria, blood, pus, and/ or leukocytes in the urine.

• May have lumbar or medial thigh pain and tenderness above the pubic bone

Incontinence- inappropriate, involuntary passage of urine. (Enuresis- Bedwetting. Occurs between 5-6 Yrs)

• Stress incontinence- happens when coughing or straining. Very common after childbirth

• Genuine stress incontinence- when a specific physical cause of the incontinence can be identified in women

• Overflow incontinence- occurs in older men when a full bladder leaks

• Urge incontinence- the leakage of urine that accompanies an intense desire to urinate with failure of restraint

Kidney Stones (Renal Calculi)- form in the renal pelvis when the urine contains excess calcium, uric acid, magnesium, etc. Usually small (3mm in diameter)

• Often, no symptoms occur until the stone begins to move down the ureter, which can cause abdominal and groin pain, nausea, and vomiting.

• Can be passed through the urethra on their own (with excessive pain). Larger ones may need to be surgically removed.

Glomerulonephritis- a rare inflammation of the glomeruli, which makes it stop functioning properly

• Dark or rust colored urine, foamy urine, or bloody urine are common with glomerulonephritis.

• Later symptoms include renal failure, systemic edema, fatigue, headaches, decreased urine output, and discoloration of the skin.

Pyelonephritis- an inflammation of the nephrons, typically due to an infection in the kidneys

• Can be accompanied by cystitis, back pain, fever, chills, nausea, and vomiting

• Can be cleared up with antibiotics

Renal Failure- when a kidney does not function properly

• A LIFE threatening condition

• Causes reduced urine output, systemic edema, and changes in mental state (due to toxins in the blood building up)

Treatments

Humans can live with only one kidney, most are born with one kidney. However, if one malfunctions, it needs to be looked at immediately.

• 2 types of treatment: Transplant surgery, or Dialysis

Transplant surgery- where a person receives a new kidney. 2 types of transplant surgery: living donor and non-living donor

• Living Donor- whose tissue matches the patient, a living person willingly donates 1 kidney.

• Non-living donor- someone who has died and agreed to donate their organs (kidneys, for example) to help others

Dialysis- performs the job of healthy kidneys by removing waste, controlling blood pressure, and maintaining homeostasis.

• Can be done internally or externally. (In the Kidneys or a Machine [Hemodialysis])

• This cannot cure kidney disease. Depending on the severity of the disease, dialysis may have to continue until the end of life (forever

For Kidney stones, during severe cases there are multiple ways to remove/ pass kidney stone(s):

• Percutaneous nephrolithotomy- removes kidney stones through small incisions in the back. (Treatment)

• Urestroscopic stone removal- uses a scope inserted through the urethra to access and remove stones in the ureter or kidney. (Treatment)

• Lithotripsy- shock waves that break down stones to passable sizes (Treatment)

Module 13 - Reproductive System

Men and women structure and functions.

Gonad- the gender specific reproductive organs that produce sex cells, and their specific hormones.

Male, gonads are “Testes” that produce sperm and testosterone.

Female, gonads are “Ovaries” that produce eggs and estrogen.

Sex cells- sperm, eggs. They contain 23 chromosomes (half of body chromo.S./ somatic cells) meaning they are Haploid cells. And are produced during Meiosis (sex cell production)

Once a sperm cell reaches a egg they combine making them 46 chromosomes and then Meiosis begins and development starts

Reproductive System (Male)

The male reproductive system consists of the Testes and Penis.

Scrotum- highly pigmented, muscular sack that extends from the body behind the penis and covers the testes.

• Control the temperature of the testes by contracting. Cold- shrink, Hot- relax

Testes- the male “Gonads”. The reproductive organs that produce Sperm and Androgens (group of hormones) like Testosterone.

• Males have 2

• About size of an egg

Seminiferous Tubules- form the bulk of each testes. Composed of developing sperm cells and where formed sperm are released into the duct system

• The production, maintaindence, storage site of sperm

• Each testis contains 1-4 minute, convoluted tubules

• Supported by a type of tissue (interstitial tissue) which produces testosterone

Epididymis- coiled tube attached to the posterior and lateral part of the testes where newly formed sperm continue to mature.

• Stores and transports sperm from the testes

Sperm- Male gamete,74 days to mature

• Fertilize the egg and transmits information

Vas Deferens- a thick muscular tube that connects testes with urethra and carries sperm out of testes

• Storage site and excretory duct of testis

• Vasectomy- vas deferens is cut to produce sterility (permanent birth control)

Pathway of Sperm: testes→ epididymis→ vas deferens→ ejaculatory duct→ urethra.

What causes lower sperm count/ poor function: smoking, alcohol, stress, overweight, meds, disorders