Ch. 2 - Terms Pertaining to the Body as a Whole Flashcards
From The Language of Medicine, 12th Edition
Cells
The cell is the fundamental unit of all living things (animal or plant). Cells are everywhere in the human body—every tissue, every organ is made up of these individual units.
cell membrane
Structure surrounding and protecting the cell. It determines what enters and leaves the cell.
nucleus
Control center of the cell. It contains chromosomes and directs the activities of the cell.
chromosomes
Rod-shaped structures in the nucleus that contain regions of DNA called genes.
[There are 46 chromosomes (23 pairs) in every cell except for the egg and sperm cells, which contain only 23 individual, unpaired chromosomes.]
DNA (deoxyribonucleic acid)
Chemical found within each chromosome. Arranged like a sequence of recipes in code, it directs the activities of the cell.
karyotype
Picture (classification) of chromosomes in the nucleus of a cell. The chromosomes are arranged in numerical order to determine their number and structure.
cytoplasm
All of the material that is outside the nucleus and yet contained within the cell membrane.
mitochondria
Rod-shaped structures in the cytoplasm that provide the principal source of energy (miniature “power plants”) for the cell.
Catabolism is the process that occurs in mitochondria. (From the Greek mitos meaning thread and chondrion meaning granule.) *HINT: Think of “mighty” mitochondria!
catabolism
Process whereby complex nutrients are broken down to simpler substances and energy is released. Cata- means down, bol means to cast, and -ism is a process.
anabolism
Process of building up large proteins from small protein pieces called amino acids. Ana- means up, bol means to cast, and -ism is a process.
metabolism
Total of the chemical processes in a cell. It includes catabolism and anabolism.
Meta- means change, bol means to cast, and -ism means a process.
endoplasmic reticulum
Network of canals within the cytoplasm of the cell. Here, large proteins are made from smaller protein pieces. (=anabolism)
Ribosomes
(RI-bo-sohmz): small granules that help the cell make proteins.
Anabolic Steroids
These drugs are similar to androgens (male hormones) in their effects on the body. They build up protein within cells.
Thyroid Gland
The thyroid gland secretes thyroid hormone (thyroxine, or T4), which stimulates metabolism in cells.
Increased levels of hormone speed up metabolism (increased energy and weight loss) and decreased levels of hormone slow down metabolism (sluggishness and weight gain).
muscle cell
long and slender and contains fibers that aid in contracting and relaxing
epithelial cell
(a lining and skin cell) may be square and flat to provide protection
nerve cell
may be long and have various fibrous extensions that aid in its job of carrying impulses
fat cell
contains large, empty spaces for fat storage
Differentiation
It’s still a scientific mystery why cells with the same DNA change or specialize into different types of cells in the developing embryo. Factors are thought to influence genes (DNA), leading to differentiation of cells. If we can figure out what causes differentiation as they mature, we may be closer to understanding what happens to cells when they revert to a more primitive, unspecialized form, as in cancer cells.
tissue
a group of similar cells working together to do a specific job.
histologist
(hist/o = tissue) ; a scientist who specializes in the study of tissues.
Epithelial tissue
located all over the body, forms the linings of internal organs, and the outer surface of the skin covering the body. It also lines exocrine and endocrine glands and is responsible for the secretions that the glands produce.
[The term epithelial originally referred to the tissue on (epi-) the breast nipple (thel/o). Now it describes all tissue that covers the outside of the body and lines the inner surface of internal organs.]
Muscle Tissue
Voluntary muscle is found in arms and legs and parts of the body where movement is under conscious control.
Involuntary muscle, found in the heart and digestive system, as well as other organs, allows movement that is not under conscious control.
Cardiac muscle is a specialized type of muscle found only in the heart. Contractions of this muscle type can be seen as a beating heart in an ultrasound scan of a 6-week-old fetus.
Connective Tissue
Examples are adipose (fat) tissue, cartilage (elastic, fibrous tissue attached to bones), bone, and blood.
Nerve Tissue
Nerve tissue conducts impulses all over the body.
Organs
Different types of tissue combine to form an organ.
For example, an organ such as the stomach is composed of muscle tissue, nerve tissue, and glandular epithelial tissue.
The medical term for internal organs is viscera (singular: viscus). Examples of abdominal viscera (organs located in the abdomen) are the liver, stomach, intestines, pancreas, spleen, and gallbladder.
Systems
groups of organs working together to perform complex functions.
For example, the mouth, esophagus, stomach, and small and large intestines are organs that do the work of the digestive system to digest food and absorb it into the bloodstream.
From cells to systems…
cells -> tissues -> organs -> systems
Organs that associate with “Digestive System”
Mouth, pharynx (throat), esophagus (tube from the throat to the stomach), stomach, intestines (small and large), liver, gallbladder, pancreas
Organs that associate with “Urinary or Excretory System”
Kidneys, ureters (tubes from the kidneys to the urinary bladder), urinary bladder, urethra (tube from the bladder to the outside of the body)
Organs that associate with “Respiratory System”
Nose, pharynx, larynx (voice box), trachea (windpipe), bronchial tubes, lungs (where the exchange of gases takes place)
Organs that associate with “Reproductive System”
Female : Ovaries, fallopian tubes, uterus (womb), vagina, mammary glands
Male : Testes and associated tubes, urethra, penis, prostate gland
Organs that associate with “Endocrine System”
Thyroid gland (in the neck), pituitary gland (at the base of the brain), sex glands (ovaries and testes), adrenal glands, pancreas (islets of Langerhans), parathyroid glands
Organs that associate with “Nervous System”
Brain, spinal cord, nerves, and collections of nerves
Organs that associate with “Circulatory System”
Heart, blood vessels (arteries, veins, and capillaries), lymphatic vessels and nodes, spleen, thymus gland
Organs that associate with “Musculoskeletal System”
Muscles, bones, and joints
Organs that associate with “Skin and sense organs”
Skin, hair, nails, sweat glands, and sebaceous (oil) glands; eye, ear, nose, and tongue
adipose tissue
Collection of fat cells.
cartilage
Flexible connective tissue often attached to bones at joints.
Cartilage forms part of the external ear and the nose. Rings of cartilage surround the trachea.
epithelial cells
Skin cells that cover the outside of the body and line the internal surfaces of organs.
histologist
Specialist in the study of tissues.
larynx (LAH-RINKS)
Voice box; located above the trachea.
*HINT: Think of the word laryngitis, which means inflammation of the voice box, and may result in losing your voice!
pharynx (FAH-RINKS)
Throat. The pharynx serves as the common passageway for food (from the mouth going to the esophagus) and air (from the nose to the trachea).
*HINT: Note that “y” comes before “n” in both pharynx and larynx.
pituitary gland
Endocrine gland at the base of the brain.
*HINT: Be careful spelling pituitary; it contains 2 i’s.
thyroid gland
Endocrine gland that surrounds the trachea in the neck.
trachea
Windpipe (tube leading from the throat and larynx to the bronchial tubes.)
ureter
One of two tubes, each leading from a single kidney to the urinary bladder.
*HINT: Spelling clue : Ureter has two e’s, and there are two ureters.
urethra
Tube from the urinary bladder to the outside of the body.
*HINT: Spelling clue : Urethra has one e, and there is only one urethra.
uterus
Womb; the organ that holds the embryo/fetus as it develops.
viscera
Internal organs in the main cavities of the body, especially in the abdomen.
body cavity
a space within the body that contains internal organs (viscera).
Organs that contains in “Cranial”
Brain, pituitary gland.
Organs that contains in “Thoracic”
Lungs, heart, esophagus, trachea, bronchial tubes, thymus gland, aorta (large artery).
The thoracic cavity is divided into two smaller cavities:
a. Pleural cavity —space surrounding each lung. The pleura is a double membrane that surrounds the lungs and protects them. If the pleura is inflamed (as in pleuritis or pleurisy), the pleural cavity may fill with fluid. This is called a pleural effusion. A collection of fluid in the peritoneal cavity is called ascites.
b. Mediastinum —centrally located space outside of and between the lungs. It contains the heart, aorta, trachea, esophagus, thymus gland, bronchial tubes, and many lymph nodes.
Organs that contains in “Abdominal/Peritoneal”
The peritoneum is the double-folded membrane surrounding the abdominal cavity. It attaches the abdominal organs to the abdominal muscles and surrounds each organ to hold it in place.
The kidneys are two bean-shaped organs situated behind the abdominal cavity (retroperitoneal area) on either side of the backbone. The abdominal cavity also contains the stomach, small and large intestines, spleen, pancreas, liver, and gallbladder.
The diaphragm (a muscular wall) divides the abdominal and thoracic cavities.
Organs that contains in “Pelvic”
Portions of the small and large intestines, rectum, urinary bladder, urethra, and ureters; uterus and vagina in the female.
Organs that contains in “Spinal”
Nerves of the spinal cord.
abdominal cavity
Space below the chest containing organs such as the liver, stomach, gallbladder, and intestines; also called the abdomen or peritoneal cavity.
cranial cavity
Space in the head containing the brain and surrounded by the skull. Cranial means pertaining to the skull.
diaphragm
Muscle separating the abdominal and thoracic cavities. The diaphragm moves up and down and aids in breathing.
dorsal (posterior)
Pertaining to the back.
mediastinum
Centrally located space outside of and between the lungs.
pelvic cavity
Space below the abdomen containing portions of the intestines, rectum, urinary bladder, and reproductive organs. Pelvic means pertaining to the pelvis, composed of the hip bones surrounding the pelvic cavity.
peritoneum
Double-folded membrane surrounding the abdominal cavity. The peritoneum attaches abdominal viscera to muscles and functions as a protective membrane (containing blood vessels and nerves) around the organs.
pleura
Double-folded membrane surrounding each lung. Pleural means pertaining to the pleura.* HINT: Don’t confuse pleural with plural, which means more than one!
pleural cavity
Space between the pleural layers.
spinal cavity
Space within the spinal column (backbones) containing the spinal cord.
thoracic cavity
Space in the chest containing the heart, lungs, bronchial tubes, trachea, esophagus, and other organs.
ventral (anterior)
Pertaining to the front.
Hypochondriac region
Right and left upper regions beneath the ribs.
