ANATOMY

Study Notes for Basic Anatomy and Physiology
Learning Objectives

  • Describe the structure, function, activities, and role of cells in physiology.

  • Explain the function of each major body system.

  • Identify how each system helps the body to maintain normal life routines.

Importance of Basic Knowledge

  • Basic knowledge of human anatomy and microbiology is important because it:

    • Helps us understand the reasons for the regulations, policies, and procedures that dictate how we perform our duties.

    • Provides a more complete picture of the importance of our place in the whole scheme of patient care.

Fundamental Definitions

  • Anatomy: The structure of the Human Body.

  • Physiology: The function of the Human Body.

Levels of Biological Organization

  • Cells → Tissues → Organs → Systems

    • Cells that are similar in structure join together to form tissue.

    • Tissues that are grouped together to perform a specific function are called organs.

    • A group of organs working together to perform a specific function is called a system.

Cells

  • Basic Unit of Life and the building blocks of the human body.

  • Invisible to the naked eye.

  • Functions within a cell:

    • Respiration

    • Nutrition

    • Energy production

    • Waste elimination

    • Reproduction and more.

  • Cells reproduce by duplication and division.

Basic Structure of Cells

  1. Nucleus: Contains genetic material.

  2. Nuclear Membrane: Surrounds the nucleus.

  3. Cytoplasm (or Protoplasm): The substance within the cell membrane.

  4. Cell Membrane: Outer barrier of the cell.

Tissues

  • Cells similar in structure organize themselves to form tissue.

Types of Tissue

  1. Epithelial Tissue: Skin, lining of body cavities.

  2. Connective Tissue: Bones, fatty tissue, blood.

  3. Muscular Tissue: Ability to contract for movement.

  4. Nerve Tissue: Communication system that carries messages to and from the brain.

Organs

  • Organs are formed when different types of tissue are grouped together to perform a specific function:

    • Example Organs:

    • Brain

    • Heart

    • Skin

Systems

  • Organs working together comprise systems.

  • Each system performs a specific function, and none are independent.

  • All must work together for the body to function as a total organism.

Homeostasis

  • Definition: "The reactions in the body that act and counteract to maintain the body in a normal physiological state."

  • Maintenance of body conditions; systems work together to maintain homeostasis.

Overview of Major Body Systems

  1. Skeletal System

  2. Muscular System

  3. Nervous System

    • Central Nervous System

    • Peripheral Nervous System

  4. Endocrine System

  5. Reproductive System

  6. Urinary and Excretory System

  7. Respiratory System

  8. Digestive System

  9. Circulatory System

Skeletal System
Functions

  • Shapes and supports the body.

  • Protects organs.

  • Allows movement.

  • Replenishes blood supply by producing blood cells.

  • Stores essential minerals.

Components

  • Bones

  • Joints

  • Cartilage

  • Tendons

  • Ligaments

Skeletal Structure

  • Axial Skeleton: Skull, chest, ribs, and spinal column.

  • Appendicular Skeleton: Bones that extend from the axial skeleton, including the arms, legs, clavicle, scapula, and the pelvic cradle (hip bone).

Terminology

  • Oste(o): Bone

  • Arthro: Joint

  • Cephal(o): Head

  • Chondr(o): Cartilage

  • Crani(o): Skull

  • Myel(o): Bone marrow

  • Sacr(o): Tailbone

  • Fibr(o): Fiber, connective tissue

  • Ili(o): Hip bone

  • Cost(o): Rib

  • Synovi(o): Joint fluid

  • Thorac(o): Chest

More About Bones

  • Bones are living tissue, capable of healing after breaks.

  • Consist of:

    • Hard outer material (cortical): Tough and strong, covered by membrane (periosteum).

    • Soft, porous inner material (cancellous bone): Contains marrow where blood cells are produced.

Joints

  • Any place where bones meet:

    • Moveable:

    • Gliding: Sliding (e.g., moving one’s head).

    • Ball & Socket: (e.g., hip and shoulder).

    • Pivot: (e.g., wrist).

    • Hinge: (knee, elbow, knuckles).

    • Immovable (e.g., skull).

Cartilage

  • Flexible connective tissue connecting bones and serving as a cushion to prevent rubbing.

  • Ossification transforms cartilage into bone.

  • Synovial fluid acts as lubricant in joints.

Tendons and Ligaments

  • Tendons: Attach muscles to bones.

  • Ligaments: Attach bones to each other.

The Muscular System
Functions

  • Movement of body through space (locomotion).

  • Movement of food and blood through the body.

  • Move air in and out of the lungs.

  • Produce heat.

Components

  1. Skeletal Muscle: Voluntary muscles attached to bones.

  2. Smooth Muscle: Involuntary muscles acting in sheets (e.g., blood vessels).

  3. Cardiac Muscle: Muscle of the heart.

Terminology

  • My(o): Muscle

  • Ten(o): Tendon

  • Fibr(o): Fiber, connective tissue

  • Fascia: Connective tissue.

Types of Muscles

  • Skeletal Muscle: Attached to bones; voluntary except for reflexes.

  • Smooth Muscle: Functions without conscious control; involuntary (e.g., blood circulation).

  • Cardiac Muscle: Works involuntarily through woven mesh fibers throughout the heart.

The Nervous System
Function

  • Acts as a communication network responding to external and internal stimuli with both automatic and conscious responses.

Components

  • Central Nervous System (CNS): Brain and Spinal Cord.

  • Peripheral Nervous System: Outer network of nerves including sensory organs.

Terminology

  • CNS: Central Nervous System

  • Encephal(o): Brain

  • Myel(o): Spinal cord

  • Neur(o): Nerve

  • Dermat(o): Skin

  • Gloss(o): Tongue

  • Nas(o): Nose

  • Ocul(o), ophthalm(o): Eye

  • Ot(o): Ear

Central Nervous System

  • Comprising Brain and Spinal Cord, considered the body's main control unit, like CPU and RAM in computers.

  • Brain Structure:

    • Cerebrum: Largest part; responsible for memory, thought, voluntary actions, and interpretation of sensory information.

    • Cerebellum: Coordinates muscular activity, body balance, posture, and equilibrium.

    • Brain Stem: Connects brain to spinal cord and controls automatic body processes.

Peripheral Nervous System

  • Connects CNS to remote parts of the body and controls involuntary functions.

Sense Organs
Overview

  • Includes eyes, ears, nose, tongue, and skin, forming a network that interfaces with the environment to process stimuli.

Functions

  • Respond to light, sound, taste, chemicals, heat, and pressure.

The Eye

  • The organ of vision; functions like a camera to transmit images to the brain via the optic nerve.

The Ear

  • Organ of hearing; sound waves are funneled to inner ear, transmitting messages to the brain.

The Nose

  • Organ of smell; warns of airborne dangers and filters impurities via cilia.

The Tongue

  • Organ of taste; acts as the body’s first defense against toxins.

The Skin

  • Largest sensory organ; contains touch receptors to distinguish between various stimuli.

The Endocrine System
Functions

  • Serves as a chemical messenger system within the body, regulating metabolism, growth, and personality traits via hormones.

Components

  • Glands:

    • Pituitary Gland: Master gland controlling other endocrine glands.

    • Thyroid Gland: Regulates metabolism and calcium levels.

    • Adrenal Glands: Release adrenaline during stress.

    • Pancreas: Controls blood sugar levels through insulin and glucagon.

    • Ovaries and Testes: Reproductive organs producing female and male hormones.

Terminology

  • Aden(o): Gland

  • Oophor: Ovary

  • Orchi: Testes

  • Adren(o): Adrenal gland

  • Thyr(o): Thyroid gland

  • Endo: Within

  • Endocrine: To secrete internally.

The Reproductive System
Function

  • Produces new life through sperm and egg cells, which contain chromosomes, and produces hormones influencing sexual characteristics.

Components

  • Ovaries

  • Uterus

  • Testes

Terminology

  • Andr(o): Male

  • Gyn(o): Female

  • Colp(o): Vagina

  • Oophor(o): Ovary

  • Orchi(o): Testes

Female Reproductive System Overview

  • Vagina: Path from entry to cervix.

  • Uterus: Hollow organ that nourishes the fetus.

  • Fallopian Tubes: Pathway for ova; connected to ovaries.

Male Reproductive System Overview

  • Two testes produce sperm, which travel through the epididymis and vas deferens, maturing along the way.

The Urinary and Excretory System
Function

  • Responsible for the formation and elimination of liquid body waste.

Components

  • Kidneys

  • Urethra

  • Ureters

  • Bladder

  • Also includes excretory structures: lungs, liver, and skin.

Terminology

  • Neph(ro): Kidney

  • Renal: Kidney

  • Uro: Urine

  • Ureter: Ureters

  • Cyst(o): Bladder

Summary of Urinary System Functions

  • Kidneys extract waste from blood to form urine, which is transported by ureters to the bladder.

  • Bladder serves as a urine reservoir with a capacity of 300cc to 500cc.

The Digestive System
Functions

  • Converts food into energy and eliminates solid body waste.

Components

  • Mouth, salivary glands, esophagus, stomach, liver, gallbladder, pancreas, small and large intestines, rectum, and anus.

Terminology

  • Chole: Bile

  • Colo: Large intestine

  • Dent(o): Tooth

  • Enter(o): Small intestine

  • Gastr(o): Stomach

  • Hepato: Liver

  • Proct(o): Rectum

  • Stomat(o): Mouth

How the Digestive System Works

  • Requires six basic categories of nutrients: protein, carbohydrates, fat, water, vitamins, and minerals.

  • The pathway through the digestive system is called the alimentary canal, approximately 30 feet long.

  • Digestion begins in the mouth, moving through the esophagus to the stomach, then to the small intestine (where absorption occurs), and onto the large intestine before waste elimination.

The Respiratory System
Functions

  • Supplies oxygen to the body and removes carbon dioxide.

Components

  • Nose, larynx, lungs, trachea, and pharynx.

Terminology

  • Aer(o): Air, gas

  • Naso, rhin(o): Nose

  • Pharyng(o): Pharynx

  • Pneum(o): Air, gas, lung

  • Spir(o): Breath, breathing

  • Thorac(o): Chest

  • Tracheo-: Trachea

  • Diaphragm: Muscle that expands and contracts to facilitate breathing.

Functioning of the Respiratory System

  • Inhales air containing approximately 20% oxygen; lungs extract oxygen while expelling carbon dioxide during exhalation.

The Circulatory System
Function

  • The primary transportation network of the body.

  • Delivers food and oxygen to cells and removes waste products.

Components

  1. Heart

  2. Blood

  3. Arteries

  4. Veins

Terminology

  • Angi(o): Vessel, channel

  • Arterio: Artery

  • Cardi(o): Heart

  • Cyan(o): Blue

  • -cyte: Cell

  • Erythr(o): Red

  • Hemat(o): Blood

  • Leuk(o): White

  • Lymph(o): Lymphatic

  • Phleb(o): Vein

  • Vas(o): Vessel, duct

Blood Composition

  • Blood as a type of connective tissue is composed of plasma, red blood cells, white blood cells, and platelets.

  • Plasma: Once known as the transport vehicle, is made up of approximately 92% water and constitutes 50% of blood supply.

  • Red Blood Cells: Most numerous, containing hemoglobin, which serves as the transport vehicle for oxygen and carbon dioxide.

  • White Blood Cells: Less numerous, serve defensive roles against pathogens.

  • Platelets: Serve in clotting and have a short lifespan of about 10 days.

Lymphatic System

  • Acts as a subsidiary system to the circulatory system and plays a vital role in the body's defense against disease through lymph nodes, collecting and returning lymphatic fluid to the blood.