Chapter 2: Terms Pertaining to the Body as a Whole

Structural organization of the body smallest to largest

cells → tissues → organs → systems

Cells

fundamental unit of all living things

major parts of a cell include:

• chromosomes

• nucleus

• cell membrane

• cytoplasm

• mitochondria

• endoplasmic reticiulum

anabolism

process of building complex molecules from simpler ones; requires energy and is used for growth, repair, and tissue maintenance - ex. building proteins from amino acids

catabolism

process of breaking down complex molecules into simpler ones; releases energy that the body can use - ex. breaking down glucose during cellular respiration

cell membrane

thin, flexible outer layer that surrounds the cell and controls what enters and leaves the cell; it helps maintain the cell’s internal environment

chromosomes

thread-like structures found in the nucleus that contain DNA and genes; humans normally 46 chromosome; 23 pairs

cytoplasm

jelly-like fluid inside the cell that surrounds the organelles; many cellular reactions take place here

DNA (deoxyribonucleic acid)

molecule that contains the genetic instructions for building, functioning, growing, and reproducing an organism

endoplasmic reticulum (ER)

network of membranes inside the cell that helps make and transport proteins and lipids; rough and smooth

rough ER

has ribosomes and makes proteins

smooth ER

makes lipids and helps detoxify harmful substances

genes

segments of DNA that contain the instructions for making specific proteins and determining inherited traits

karyotype

an organized picture or display of a person’s chromosomes used to detect chromosome number and abnormalities

metabolism

the sum of all chemical reactions in the body, including both anabolism (building) and catabolism (breaking down)

mitochondria

organelles known as the “powerhouse of the cell”; they produce ATP (energy) through cellular respiration

nucleus

the cell’s control center; It contains the DNA and directs the cell’s activities, including growth, metabolism, and reproduction

cells are specialized to carry out

individual functions

types of cells include:

• muscle cell

• nerve cell

• epithelial cell

• fat cell

what cell

muscle cell

what cell

nerve cell

what cell

epithelial cell

what cell

fat cell

tissues

a group of similar cells working together to do a specific job

organs

different types of tissue combine to form an organ

systems

groups of organs working together to perform complex functions

adipose tissue

connective tissue that stores fat (lipids); cushions organs, insulates the body, and serves as an energy reserve

cartilage

a strong, flexible connective tissue that supports the body and cushions joints; it is found in the nose, ears, trachea, and between bones

epithelial cells

cells that form epithelium, the tissue that covers body surfaces, lines organs and cavities, and forms glands; they protect the body and help with absorption and secretion

histologist

a scientist or healthcare of professional who studies the microscopic structure of tissues

larynx

the voice box, located between the pharynx and trachea; it contains the vocal cords and helps with breathing, speaking, and protecting the airway

pharynx

throat; a muscular passageway that carries air from the nose and mouth to the larynx and food to the esophagus

pituitary gland

a small gland at the base of the brain called the “master gland”; it produces hormones that regulate growth, reproduction, metabolism, and other glands t

thyroid gland

a butterfly-shaped gland in the neck that produces hormones regulating metabolism, growth, and development

trachea

windpipe, tube that carries air from the larynx to the bronchi and lungs

ureter

one of two tubes that carry urine from the kidneys to the bladder

urethra

the tube that carries urine from the bladder to the outside of the body; in males, it also carries semen

uterus

the womb, hollow, muscular group organ where a fertilized egg implants and a fetus develops during pregnancy

viscera

the internal organs, especially those located in the chest and abdominal cavities (such as heart, lungs, stomach, liver, and intestines)

body cavities

the spaces within the body that contain internal organs (viscera)

what are the body cavities

• cranial

• thoracic

• abdominopelvic

• spinal

cranial cavity

brain

thoracic cavity

• lungs

• heart

• esophagus

• trachea

• bronchial tubes

• thymus gland

• aorta

abdominal cavity

• stomach

• small and large intestines

• spleen

• pancreas

• liver

• gall bladder

pelvic cavity

• portions of the small and large intestine

• bladder

• rectum

• urethra

• ureters

• uterus and vagina in female

spinal cavity

nerves of the spinal cord

which body cavity contains the pleural cavity and the mediastinum

thoracic cavity

which body cavity contains the peritoneum

abdominal cavity

lung

one of the two organs responsible for gas exchange, bringing oxygen into the blood and removing carbon dioxide

diaphragm

a large dome-shaped muscle below the lungs that is the primary muscle of breathing; when it contracts, you inhale

liver

body’s largest internal organ, it produces bile, detoxifies harmful substances, stores nutrients, and helps regulate metabolism

gallbladder

small sac beneath the liver that stores and concentrates bile, releasing it into the small intestine to help digest fats

pancreas

a gland that produces digestive enzymes and hormones like insulin and glucagon, which regulate blood sugar

colon (large intestine)

the longest part of the large intestine; it absorbs water and electrolytes and forms and stores feces

appendix

small, finger-like pouch attached to the beginning of the large intestine; it may play a role in immune function and gut bacteria

bladder (urinary bladder)

muscular sac that stores urine until it is excreted through the urethra

aorta

the largest artery in the body; it carries oxygen-rich blood from the left ventricle of the heart to the rest of the body

heart

muscular organ that pumps blood throughout the body, supplying oxygen and nutrients to tissues

spleen

an organ of the lymphatic system that filters blood, removes old red blood cells, stores platelets, and helps fight infection

stomach

muscular organ that stores food and begins digestion by mixing food with acid and digestive enzymes

small intestine

main site of digesting and nutrient absorption; consists if the duodenum, jejunum, and ileum

sigmoid colon

an s-shaped section of the large intestine that connects the descending colon to the rectum and stores feces before elimination

abdominal cavity

upper part of abdominopelvic cavity that contains the stomach, liver, gallbladder, spleen, pancreas, kidneys, and most of the intestines

cranial cavity

cavity within the skull that contains and protects the brain

dorsal (posterior)

back side of the body; dorsal body cavity includes the cranial and spinal cavities

mediastinum

central compartment of the thoracic cavity between the lungs; contains the heart, trachea, esophagus, thymus, and major blood vessels

pelvic cavity

lower portion of abdominopelvic cavity that contains urinary bladder, reproductive organs, and rectum

peritoneum

serous membrane that surrounds each lung and lines the inside of the chest wall

pleural cavity

thin, fluid-filled space between the two layers of the pleura surrounding each lung

spinal cavity (vertebral cavity)

cavity within the vertebral column that contains and protects spinal cord

thoracic cavity

chest cavity, it contains the lungs in the pleural cavities and the mediastinum which contains the heart, trachea, esophagus, and major blood vessels

ventral (anterior)

front side of the body; ventral body cavity includes the thoracic and abdominopelvic cavities

right hypochondriac region

• upper right abdomen, below the ribs

• right lobe of liver, gallbladder, upper right kidney,cpart of the small intestine

left hypochondriac region

• upper left abdomen, below the ribs

• spleen, upper left kidney, part of the stomach, tail of pancreas

epigastric region

• upper middle abdomen, above the stomach

• stomach, part of the liver, pancreas, duodenum

right lumbar region

• middle right side of abdomen

• ascending colon, right kidney, small intestine

left lumbar region

• middle left side of the abdomen

• descending colon, left kidney, small intestine

umbilical region

• center of the abdomen, around belly button

• small intestine, transverse colon

right inguinal (iliac) region

• lower right abdomen

• appendix, cecum, small intestine

left inguinal (iliac) region

• lower left abdomen

• sigmoid colon, descending colon, small intestine

Hypogastric (pubic) region

• lower middle abdomen, below umbilicus

• urinary bladder, small intestine, reproductive organs (uterus in females), part of the sigmoid colon

abdominopelvic quadrants

• right upper quadrant (RUQ)

• left upper quadrant (LUQ)

• right lower quadrant (RLQ)

• left lower quadrant (LLQ)

right upper quadrant (RUQ)

contains liver (right lobe), gallbladder, part of the pancreas, parts of small and large intestines

left upper quadrant (LUQ)

contains liver (left lobe), stomach, spleen, part of the pancreas, parts of small and large intestines

right lower quadrant (RLQ)

contains parts of small and large intestines, right ovary, right fallopian tube, appendix, right ureter

left lower quadrant (LLQ)

contains parts of small and large intestines, left ovary, left fallopian tube, left ureter

anatomical divisions of the back

• cervical

• thoracic

• lumbar

• sacral

• coccygeal

cats think liars suck cock

vertebra

a single bone of the spine

vertebrae

plural of vertebra; there are 33 bones that make up spinal column

spinal column (vertebral column)

• backbone

• flexible column made of vertebrae that supports the body, protects the spinal cord, and allows movement

spinal cord

• long bundle of nervous tissue that extends from the brain through the spinal canal

• carries messages between brain and rest of the body

disc (intervertebral disc)

• cushion of fibrocartilage located between adjacent vertebrae

• absorbs shock, provides flexibility, and prevents the vertebrae from rubbing together

anterior

towards front of body

posterior

toward the back of the body

deep

further away from the body surface, more internal

superficial

closer to or on the body surface

proximal

closer to the point of attachment or origin

distal

farther from the point of attachment or origin

inferior

below; toward the feet

superior

above; toward the head