2.1 Introduction to Body Organization and Anatomical Terminology

homeostasis

state of equilibrium that is maintained in the body’s internal environment to support and sustain life

anatomical terminology

terms used to describe the human body. they also describe specific locations, positions, or directions of the human body

what two greek words is the term anatomy created from?

ana (apart) and tome (to cut)

levels of organization of human body

atoms→molecules→organelles→cells→tissues→organs→organ systems→organism

cell

basic building block of the human body

tissue

grouping of similar cells that work together to perform a specialized function

4 types of tissues

epithelial, connective, muscle, and nervous

epithelial

forms outer surfaces of the body and lines body cavities and tubes that lead to exterior of the body

functions of epithelial tissue

1)protection: forms physical barrier over underlying tissue

2)secretion: secretes hormones/enzymes/fluids from various glands

3)absorption: lines small intestine and aids the body in taking nutrients from food

4)excretion: waste products from kidneys excreted and sweat from the skin

5)diffusion: of gases, liquids, and nutrients occurs

connective tissue

• builds support for the body’s organs and muscle sheaths and also connects muscles to bones and bones to joints

• most abdundant tissue in the body

muscle tissue

forms muscles throughout the body

3 types of muscle tissue

skeletal, smooth, and cardiac

skeletal muscle

voluntarily controlled and is used by the body for movement and posture

smooth muscle

• involuntary controlled and is used by body for movement and posture

• found in organs such as esophagus, stomach, intestine, and bladder

• not under conscious control and is controlled by autonomic nervous sytem

cardiac muscle

• found in the heart

• also involuntary and controlled by autonomic nervous system

nervous tissue

• functions to communicate throughout the body

• nerve cells are excitable and can conduct electricity

• coordinates and controls functions of the body

organs

• different tissue types combine to form organs

• structures in body that perform specific purposes

body systems

• groups of different organs functioning together for a common purpose

integumentary system

protective membrane, temperature regulator, and sensory receptor

skeletal system

• framework and movement

• shape, support, protection, and storage place for minerals

• movement made possible by joints

muscular system

• framework and movement

• muscles produce movement, maintain posture, and produce heat

nervous sytem

• communication and control

• transmits impulses, responds to change, is responsible for communication, and exercises control over various parts of the body

endocrine system

• communication and control

• glands produce hormones, chemical messengers, that provide for communication and control over various parts of the body

cardiovascular system

• transportation and immunity

• transports oxygen and CO2, delivers nutrients and hormones, and removes waste products

blood and the lymphatic system

• transportation and immunity

• transports oxygen and CO2, chemical substances and cells that act to protect the body from foreign substances

• stimulates immune response, protects the body, and transports proteins and fluids

respiratory system

• distribution and elimination

• furnishes oxygen for use by individual tissue cells and removes their gaseous waste product, CO2

digestive system

• distribution and elimination

• digestion, absorption, and elimination

urinary system

• distribution and elimination

• produces urine, transports urine and eliminates urine

  • kidneys help maintain electrolyte, water, and acid-base balance of the body

reproductive system

• cycle of life

• responsible for sexual characteristics of the male and female

• proper functioning ensures survival of the human race

anatomical position

body is standing upright, head facing forward, and arms extended y the side of the body with the palms faced to the front

what is the body divided into?

imaginary sections called body planes.

what are the 4 body planes

sagittal, midsaggital, transverse/horizontal, and coronary/frontal

sagittal plane

divides body vertically into right and left sections

midsagittal plane

divides body into right and left halves at the midline

transverse/horizontal plane

divides into superior and inferior sections

coronal/frontal plane

divides body into anterior and posterior sections

directional terms

• location of a body part in relation to another body part

• describe where something is located, whether a body part or a sign or symptom

• can exist in opposing pairs

superior

• combining form: none

• description: above, in an upward direction, toward the head

• example: the neck of the body is superior to the abdomen

inferior

• combining form: infer/o

• description: below, in a downward direction; more toward the feet

• example: the feet are inferior to the abdomen

anterior

• combining form: anter/o

• description: in front of, before, the front side of body

• ex: the nose is located on the anterior side of the head

posterior

• combining form: poster/o

• toward the back, backside, of the body

• the buttocks are located posterior of the body

cephalic

• cephal/o

• pertaining to the head, superior in position

• when a fetus has cephalic presentation at birth, it means that any part of the head is the presenting part

caudal

• caud/o

• pertaining to the tail, inferior in position

• cauda equina is a specific part of the spinal cord that is located at the bottom

medial

• medi/o

• nearest to the midline or middle

• the umbilicus is in the medial area of the abdomen

lateral

• later/o

• to the side away from middle

• the arms are lateral to the abdomen

proximal

• proxim/o

• nearest to the point of attachment, near the point of origin

• the elbow is proximal to the hand

distal

• dist/o

• away from the point of attachment, far from the point of origin

• the hand is distal to the elbow

deep

• further below the surface

• the deep fascia is a fibrous membrane that covers the muscles, nerves, and vessels

superficial

• nearer the surface

• superficial brachial artery is an artery in the arm that is above the medial nerve

body cavities

• hollow spaces that contain organs

• enclosed with membranes that are specific to the cavities that they cover

what are the 4 cavities?

• 2 cavities on the posterior side of the body

  • cranial and spinal cavity

• 2 cavities on the anterior side of the body

  • thoracic and abdominopelvic cavity

cranial cavity

• contains the brain

• brain is protected by a membrane sac called the meninges

• protected by the skull too

spinal cavity

• contains the spinal cord

• protected by the cervical, thoracic, and lumbar vertebrae and is also covered by the meninges

thoracic cavity

• contains hearts, lungs, esophagus, trachea, aorta, and thymus gland

• protected by the ribs and is separated from the abdominopelvic cavity by the diaphragm

2 cavities of the thoracic

1) mediastinum: central region of the thoracic cavity and contains the heart, trachea, esophagus, aorta, and thymus gland

2) pleural: 2, located lateral to the mediastinum on either side. each contains a lung and is covered by membrane called the pleura

abdominopelvic cavity

• divided into superior section of the abdominal cavity and inferior section of the pelvic cavity

• covered by a membrane called the peritoneum

• abdominal cavity

  • stomach, liver, gallbladder, spleen, pancreas, small intestine, and most of large as well

• pelvic cavity

  • urinary bladder, ureters, urethra, last section of large intestine, also reproductive organs

    • females: vagina, uterus, ovaries, fallopian tubes

    • males: prostate gland, seminal vesicles, bulbourethral gland, vas deferens

4 clinical divisions of the abdominopelvic cavity

right upper quadrant (RUQ): majority of liver, right kidney, portion of large intestine, small portion of pancreas, gallbladder, section of small intestine

right lower quadrant (RLQ): portions of large intestine, small intestine, right ureter, appendix, females (right ovary and right fallopian tube)

left upper quadrant (LUQ): small portion of the liver, spleen, left kidney, stomach, majority of pancreas, portions of small/large intestines

left lower quadrant (LLQ): portions of the small/large intestines, left ureter, female (left ovary and uterine tube)

9 different anatomical divisions

1)right hypochondriac (below, cartilage, pertaining to)region: the right lateral side of the upper row under the ribs that connect to the sternum via cartilage

2)epigastic region (above, stomach, pertaining to): middle area of the upper row that is above the stomach

3)left hypochondria: left lateral side of the upper row

4)right lumbar (low back, pertaining to): right lateral side of the middle row, near the waist

5)umbilical: middle area of the middle row containing the umbilicus

6)left lumbar: left lateral side of the middle row

7) right iliac (ilium, pertaining to): right lateral side of the lower row near the groin

8) hypogastric: middle area of the lower row

9)left iliac: left lateral side of the lower row