Mcat Word Du Jour - Princeton Review Website

Front 1

Atelectasis

Back 1

Collapse of the lung, as might occur when air enters the pleural cavity due to a chest wound.

Front 2

Tidal Volume

Back 2

The volume of air inhaled and exhaled in a normal, resting breath, typically about 500 ml.

Front 3

Ureters

Back 3

The tubes that carry urine from the kidneys to the bladder.

Front 4

Nucleus Pulposus

Back 4

The soft inner sphere of an intervertebral disk. It acts like a rubber ball when compressed, and provides elasticity and compressibility to the disk. Its expansion is limited by an outer ring of fibrocartilage.

Front 5

Transduction

Back 5

The transfer by a lysogenic virus of a portion of a host cell genome to a new host.

Front 6

Colostrum

Back 6

Highly nutritious, yellowish “pre-milk” secreted by the mammary glands for two or three days after childbirth until the true milk is produced. Colostrum is high in proteins and low in fat, and contains large amounts of IgA antibodies that help to protect

Front 7

Pulmonary Semilunar Valve

Back 7

The valve separating the right ventricle from the pulmonary artery.

Front 8

Relative Refractory Period

Back 8

The period of time following an action potential when it is possible, but difficult, for the neuron to fire a second action potential due to the fact that the membrane is further from threshold potential.

Front 9

Adventitia

Back 9

The outermost membranous covering of an organ.

Front 10

Glial Cell

Back 10

One of four types of supporting cells found in the central nervous system. The glial cells include astrocytes, ependymal cells, microglia, and oligodendrocytes.

Front 11

Amber Suppressor

Back 11

A tRNA coded for by a mutant allele so that its anticodon is altered in such a way as to insert an amino acid at an amber codon (UAG, stop codon) during translation.

Front 12

Monocistronic mRNA

Back 12

mRNA that codes for a single type of protein, such as is found in eukaryotic cells.

Front 13

Dermatome

Back 13

The area of skin that is innervated by the cutaneous branches of a single spinal nerve.

Front 14

Kyphosis

Back 14

An abnormal exaggerated thoracic curvature of the vertebral column (“hunchback”) commonly seen in older, postmenopausal women with symptoms of calcium deficiency (e.g., osteomalacia, osteoporosis).

Front 15

Cytokine

Back 15

Proteins made and secreted by cells that affect the behavior of other cells. The best known cytokines are those secreted by the cells of the immune system that stimulate proliferation of other immune system cells (e.g., IL-2, IL-4, etc.).

Front 16

Falciform Ligament

Back 16

The large ligament that separates the left and right lobes of the liver and suspends the liver from the anterior abdominal wall and diaphragm.

Front 17

Thrombocytopenia

Back 17

A condition in which the number of platelets in the blood is reduced. This causes spontaneous hemorrhage from small blood vessels throughout the body.

Front 18

Testicular feminization

Back 18

The development of a female phenotype in an individual with an XY genotype.

Front 19

Chiasma

Back 19

A site of crossing-over, as observed in homologous chromosomes during meiosis.

Front 20

Gluconeogenesis

Back 20

The formation of glucose from non-carbohydrate precursors.

Front 21

Sinoatrial node

Back 21

A region of specialized cardiac muscle cells in the right atrium of the heart that initiate the impulse for heart contraction. For this reason it is known as the "pacemaker" of the heart.

Front 22

Hypercapnia

Back 22

High blood levels of carbon dioxide.

Front 23

Achondroplasia

Back 23

An abnormal genetic condition in which cartilage formation (and subsequently endochondral bone growth) are defective. This results in an abnormally short stature and an enlarged head.

Front 24

Circle of Willis

Back 24

An arterial anastomosis connecting the anterior and posterior blood supplies to the brain.

Front 25

Portal Triad

Back 25

A structure consisting of three vessels (a hepatic artery, a hepatic portal vein, and a bile duct) found at each of the six corners of the hexagonal-shaped liver lobules.

Front 26

Gubernaculum

Back 26

The strong, fibrous cord that mechanically guides the testes into the scrotal sac approximately two months before birth.

Front 27

Hypervariable Site

Back 27

The portion of the variable region of an antibody gene that determines the antibody specificity.

Front 28

Antipruritic Drugs

Back 28

Lotions and other forms of medication used to reduce itching.

Front 29

Active Immunity

Back 29

Long-term immunity acquired by encountering an antigen and developing memory cells.

Front 30

Detrusor Muscle

Back 30

The muscular wall of the bladder.

Front 31

Parotid Gland

Back 31

The largest extrinsic (outside the oral cavity) salivary gland. It is located anterior to the ear. This is the gland affected by a mumps infection.

Front 32

Signal Sequence

Back 32

A short sequence of amino acids, usually found at the N-terminus of a protein being translated, that directs the ribosome and its associated mRNA to the membranes of the rough endoplasmic reticulum, where translation will be completed.

Front 33

Lymphocyte

Back 33

The second most common of the five classes of leukocytes. Lymphocytes are involved in specific immunity and include two cell types, B-cells and T-cells. B-cells produce and secrete antibodies and T-cells are involved in cellular immunity.

Front 34

Chief Cells

Back 34

Pepsinogen-secreting cells found at the bottom of the gastric glands.

Front 35

Autograft

Back 35

Tissue grafts transplanted from one body location to another in the same person.

Front 36

Canaliculus

Back 36

Very small tube or channel, such as is found between lacunae (connecting them together) in compact bone.

Front 37

Cortical Reaction

Back 37

The release of the contents of the cortical granules of an oocyte that occurs after fertilization. This requires an increase in intracellular calcium and causes the separation of the oocyte plasma membrane from the zona pellucida...

Front 38

Stroke Volume

Back 38

The volume of blood pumped out of the heart in a single contraction.

Front 39

Hyperkalemia

Back 39

High blood levels of potassium.