MCAT Biology Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

Oligodendrocytes

A

Cells that produce myelin in the central nervous system.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Myelin sheath

A

Electrically insulating substance that surrounds axons, secreted by Schwann cells and oligodendrocytes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Anaphase

A

The mitotic phase involving the separation of chromosomes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Cell wall

A

The cell’s protection from external stimuli and desiccation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Heterozygotes

A

Organisms containing two different alleles for the same gene on corresponding chromosomes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Neural crest cells

A

Cells at the tip of the neural fold; this group of cells gives rise to many components of the peripheral nervous system.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Microfilaments

A

Solid rods of actin that are involved in cell movement and cell wall support.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Appendicular skeleton

A

The bones of the pelvis, pectoral girdles, and limbs.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Cholecystokinin

A

A hormone that is secreted by the duodenum in response to the presence of chyme. It stimulates the release of bile and pancreatic enzymes into the small intestine.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Inversion

A

A form of chromosomal rearrangement in which a portion of a chromosome breaks off and rejoins the same chromosome in the reverse position.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Adrenal medulla

A

Synthesizes and releases epinephrine and norepinephrine, which stimulates an increase in the metabolic rate and blood glucose levels.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Bacteriophages

A

Viruses that can infect bacteria.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Cornea

A

Transparent covering in front of the eye that refracts light and helps keep the eye in focus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Osmoregulation

A

Maintenance of water and solute concentrations.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Humoral immunity

A

The synthesis of specific antibodies by activated B-cells in response to an antigen. These antibodies bind to the antigen and either clump together to become insoluble or attract other cells that engulf them.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Exteroceptor

A

Type of sensory receptor that monitors external signals such as light, sound, and temperature.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Endometrium

A

The mucosal lining of the uterus where the embryo implants. Progesterone is necessary to maintain it during pregnancy.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Iris

A

Muscular tissue in the eye that controls the amount of light allowed in through the pupil.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Penetrance

A

The percentage of people in a population with a certain genotype who express the associated phenotype.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Microtubules

A

Structures that maintain cell shape, form the spindle, and provide tracks along which organelles can move. They also compose cilia and flagella.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Gametocyte

A

A cell from which gametes form by meiotic division, especially a spermatocyte or an oocyte.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Enzymes

A

Catalysts (usually proteins) that accelerate reactions by reducing the activation energy without being consumed or altered by the reaction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Capillaries

A

Blood vessels composed of a single layer of endothelial cells, facilitating exchange between the blood and interstitial fluid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Homozygotes

A

Organisms containing two identical copies of the same gene on corresponding chromosomes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Glycogen

A

The primary form in which carbohydrates are stored in the liver.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Directional selection

A

Type of natural selection where one extreme phenotype is favored over the mean phenotype and other extreme phenotypes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Parthenogenesis

A

The development of an unfertilized egg into an adult organism.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Autotroph

A

An organism that can harness sunlight to create energy via photosynthesis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Zygote

A

A fertilized egg.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Fluid mosaic model

A

A model that states that a cell membrane consists of a phospholipid bilayer with proteins embedded throughout.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Intramembranous ossification

A

This is the transformation of mesenchymal tissue into bone.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Lock and key theory

A

Theory of enzyme catalysis stating the active site’s structure is complementary to the structure of the substrate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Mendel’s Law of Independent Assortment

A

The alleles of different genes assort independently during meiosis. We now know that this is true only for unlinked genes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Helicase

A

An enzyme that unwinds the double helix of a DNA molecule and separates the two strands, allowing replication to take place.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Coronary arteries

A

Blood vessels that supply the heart with oxygenated blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Adrenocorticotropic hormone

A

Synthesized and released by the anterior pituitary, it stimulates the adrenal cortex to synthesize and secrete glucocorticoids.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Seminiferous tubules (testes), epididymis, vas deferens, ejaculatory duct, (nothing), urethra, penis

A

Name the structures of the male reproductive tract using the Kaplan acronym (SEVEN UP).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Fovea

A

The region of the retina with a high density of cones.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Osmosis

A

The passive movement of water; diffusion of water.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Pyloric glands

A

Glands located in the walls of the stomach that secrete the hormone gastrin in response to certain substances in food.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Ventricles

A

The muscular lower chambers of the heart.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Genotype

A

Genetic makeup of an individual

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Testosterone

A

Hormone secreted by the interstitial cells of the testes. It is responsible for embryonic sexual differentiation, male sexual development, and maintenance of masculine secondary sexual characteristics.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Lagging strand

A

During DNA replication, the strand of DNA that is synthesized in small fragments and then ligated together.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Homeostasis

A

The maintenance of a stable internal environment.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Diploid

A

Cells that have two copies of each chromosome, like somatic eukaryotic cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Large intestine

A

Section of the GI tract that consists of the cecum, colon, and rectum. The major function is to absorb salts and water.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Rough endoplasmic reticulum

A

Serves as an attachment point for ribosomes, which functions in protein synthesis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Autonomic nervous system

A

Division of the peripheral nervous system that is responsible for involuntary movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Monosynaptic reflex

A

Reflex pathway that has only one synapse between the sensory neuron and the motor neuron.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Posterior pituitary

A

Stores and releases hormones synthesized in the hypothalamus. Release of hormones is triggered by an action potential that originates in the hypothalamus.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Efferent neurons

A

Neurons that carry information from the central nervous system to other parts of the body.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Negative pressure breathing

A

The contraction of the diaphragm and the intercostal muscles increases the volume of the thoracic cavity, reducing the pressure in the intrapleural space.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Nephron

A

The functional unit of the kidney.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Purines

A

Adenine and guanine. They have characteristic bicyclic nitrogenous bases and pair with pyrimidines in double-stranded DNA.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Diastole

A

The stage of the heart cycle in which the heart muscle relaxes and collects blood into its four chambers.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

Osteoclasts

A

Cells in the bone matrix that are involved in bone degradation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

Hypothalamus

A

Structure responsible for visceral functions such as hunger, thirst, and sex drive.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

Expressivity

A

The degree to which an organism expresses its genotype.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

Spermatozoa

A

Mature sperm specialized for transporting a male’s genetic information to the ovum.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

Glomerulus

A

Network of capillaries within the Bowman’s capsule that serves as the site of filtration. Blood cells and proteins are too large to be filtered, but ions, glucose, and amino acids readily pass into the filtrate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

Arteries

A

Vessels that carry blood away from the heart. These vessels are muscular and do not have valves.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

Haploid

A

Cells that have only one copy of each chromosome, such as human gametes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

DNA ligase

A

Enzyme that covalently links the Okazaki fragments together during DNA replication

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

Repressible system

A

A system that is normally “turned on” but can be inactivated by the addition of a repressor or corepressor.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

Semen

A

The fluid discharged during ejaculation, consisting of sperm cells and seminal fluid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

Small intestine

A

It can be divided into three sections; the duodenum, jejunum, and ileum. Most digestion takes place in the duodenum, and most absorption takes place in the jejunum and the ileum.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

Alleles

A

Genes coding for alternative forms of a given trait.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

Disjunction

A

The separation of homologous chromosomes during anaphase I of meiosis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

Vestigial structures

A

Structures that have lost ancestral function, like the human tailbone.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

Transcription

A

The process whereby mRNA is synthesized from a DNA template.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

Synaptic terminals

A

Ends of axons that form one side of the synaptic cleft; the location where neurotransmitters are stored.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

Proximal convoluted tubule

A

Site where glucose, amino acids, and other important organic molecules are reabsorbed from the filtrate into the interestitial fluid. It lies in the cortex of the kidney.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

Cerebellum

A

Part of the brain that is responsible for coordination.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

Adaptive radiation

A

The emergence of a number of distinct lineages from a single ancestral species.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

Cytoskeleton

A

Gives cell mechanical support, maintains cell shape, and functions in cell motility. Composed of microtubules, microfilaments, and intermediate filaments.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

Transverse tubules

A

A system of structures that provides channels for ion flow throughout the muscle fibers to facilitate the propagation of electrical signals from the nervous system.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

Prolactin

A

A hormone synthesized and released by the anterior pituitary that stimulates milk production and secretion in female mammary glands.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

Tetrad

A

Four chromatids that result when a pair of homologous chromosomes synapse during prophase I of meiosis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

Veins

A

Vessels that carry blood toward the heart. They have thin walls and have valves to prevent backflow.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

Golgi apparatus

A

Receives vesicles from the smooth ER, modifies them, and repackages them into vesicles for distribution.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

Right atrium, tricuspid valve, right ventricle, pulmonary arteries, pulmonary capillaries, pulmonary veins, left atrium, bicuspid valve, left ventricle, aorta, arteries, arterioles, vapillaries, venules, veins, vena cava

A

Starting with the right atrium, trace the path of blood flow throughout the body.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

Placenta

A

An organ formed by the uterus and extraembryonic membranes of the fetus. It contains a network of capillaries through which exchange between the fetal and maternal circulations take place.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

Medulla oblongata

A

The part of the brain that controls many basic, autonomic functions, such as breathing and heart rate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

Pyrimidines

A

Cytosine and thymine. They have characteristic monocyclic nitrogenous bases and pair with purines in double-stranded DNA.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

Ganglion

A

A group of neural cell bodies in the peripheral nervous system.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

Nodes of Ranvier

A

Gaps between segments of myelin sheath where action potentials can propagate, allowing for saltatory conduction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

Inner cell mass

A

The group of cells in a blastocyst that develop into the embryo.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

Cerebral cortex

A

Processes and integrates sensory input and motor response, and controls memory.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

Inducible system

A

A system in which a repressor bound to an operator prevents transcription. Addition of inducers can activate it by preventinr the repressor from binding to the operator.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
91
Q

Zymogen

A

Enzyme that must undergo processing before it can catalyze reactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
92
Q

Fatty acid activation

A

The usage of two ATP molecules to convert fats into acetyl CoA for usage in the citric acid cycle.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
93
Q

Hyperpolarization

A

State where the potential across the membrane is more negative than the resting potential.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
94
Q

Polar body

A

A small, short-lived haploid cell created during oogenesis that receives very little cytoplasm, organelles, and nutrients.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
95
Q

Phenotype

A

The physical manifestation of an individual’s genotype

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
96
Q

Retrovirus

A

An RNA virus that codes for the enzyme reverse transcriptase, which uses the RNA as a template for DNA synthesis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
97
Q

Telophase

A

The mitotic phase where cytokinesis occurs.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
98
Q

Depolarization

A

A process that occurs when the voltage-gated Na+ channels open, allowing Na+ to rush into the cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
99
Q

Residual volume

A

The amount of air that must remain in the lung at all times in order to prevent collapse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
100
Q

Ribonucleic acid

A

Similar to DNA but the sugar deoxyribose is replaced with the sugar ribose, and adenine pairs with uracil instead of thymine.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
101
Q

Incomplete dominance

A

Describes a situation in which an organism heterozygous for a trait will have a phenotype that is intermediate both alleles.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
102
Q

Sarcoplasmic reticulum

A

A modified form of endoplasmic reticulum, which stores calcium that is use to trigger contraction when muscle is stimulated.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
103
Q

Pyloric sphincter

A

A valve between the stomach and the small intestine that regulates the flow of chyme into the small intestine.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
104
Q

Cell theory

A

States that all living things are composed of cells; cells are the basic functional unit of life; cells arise only from pre-existing cells, and carry their genetic information in the form of DNA.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
105
Q

Hypodermis

A

Layer of loose connective tissue below the dermis that binds the dermis to the body.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
106
Q

Leukocytes

A

White blood cells; the component of blood involved in cell defense and immunity. Types include neutrophils, basophils, eosinophils, lymphocytes, and monocytes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
107
Q

Frameshift mutation

A

Mutation in which a number of nucleotides (except multiples of three) are either deleted or inserted. Such mutations lead to a shift in the DNA reading frame and often result in the translation of nonfunctional proteins.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
108
Q

Pancreas

A

Secreates amylase, trypsin, chymotrypsin, carboxypeptidase, and lipase into the small intestine.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
109
Q

Punctuated equilibrium

A

A model that holds that evolution is characterized by long periods of stasis punctuated by rapid evolutionary changes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
110
Q

Pyruvate decarboxylation

A

The stage of aerobic cellular respiration that comes after glycolysis. Pyruvate is oxidized to acetate, which combines with coenzyme A to form acetyl CoA in the mitochondrial matrix. This process result in the formation of one NADH per pyruvate or two NADH per glucose.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
111
Q

Secondary immune response

A

Subsequent infections by antigens trigger a more immediate response by the memory cells produced during the primary response.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
112
Q

Osteoblasts

A

Cells in the bone tissue that secrete organic constituents of the bone matrix.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
113
Q

Substrate

A

A molecule upon which an enzyme acts.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
114
Q

Centrosome

A

A region of the cell that contains the centrioles.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
115
Q

Interkinesis

A

A short rest period between meiosis I and meiosis II. DNA is not replicated.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
116
Q

Prophage

A

A virus that has integrated its DNA into the host cell’s DNA.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
117
Q

Hepatic portal vein

A

Carries nutrients absorbed in the small intestine to the liver, where they are modified to enter circulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
118
Q

Point mutation

A

Mutation in which one nucleotide base is substituted for another. The protein products are often functional.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
119
Q

Exocytosis

A

A process in which a vesicle within the cell fuses with the membrane and releases its contents to the extracellular medium.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
120
Q

Threshold value

A

The minimal value that must be reached in order for a system to respond. Muscle fibers and neurons both exhibit this all-or-none response.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
121
Q

Progesterone

A

Hormone synthesized and released by the ovaries, corpus luteum, and placenta. During the luteal phase of the menstrual cycle, the corpus luteum secretes it, which, along with estrogen, stimulates the development and maintenance of the endometrial walls for implantation of the embryo.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
122
Q

Superior vena cava

A

A large vein that returns deoxygenated blood from the head and neck to the right atrium of the heart.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
123
Q

Prophase

A

The mitotic phase where chromosome condensation and spindle formation occurs. In mesiosis, crossing over occurs here.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
124
Q

Rh factor

A

An antigen on the surface of erythrocytes, classified as either positive (possessing the factor) or negative (not possessing the factor).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
125
Q

mRNA

A

Class of RNA that is created from the transcription of DNA (and post-transcriptional processing in eukaryotes).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
126
Q

Somatostatin

A

Produced and secreted by the delta cells of the pancreas, inhibits the release of glucagon, insulin, and several other hormones throughout the body.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
127
Q

Gluconeogenesis

A

A process in the liver by which glucose is produced using by-products of glycolysis, lipids, or fats.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
128
Q

Amnion

A

The innermost extraembryonic membrane that contains amniotic fluid in which the growing fetus is suspended.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
129
Q

Red fibers

A

Slow-twitch muscle fibers. They are primarily aerobic and contain many mitochondria and myoglobin.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
130
Q

Steroid hormones

A

Nonpolar hormones that permeate the cell membrane and act by binding to intracellular receptors.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
131
Q

Codon

A

Nonoverlapping group of three nucleotides. During translation, each is read to determine the next step in protein synthesis, usually by dictating which amino acid is added.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
132
Q

Mesoderm

A

Primary germ layer that gives rise to the musculoskeletal system, circulatory system, excretory system, gonads, connective tissue, and portions of the digestive and respiratory organs.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
133
Q

Operon

A

A group of genes or segment of DNA that regulates (bacterial) transcription.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
134
Q

Lysogenic cycle

A

Phase of viral replication in which the DNA of the bacteriophage becomes integrated in the host’s genome and replicates as the bacteria replicates.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
135
Q

Post-transcriptional RNA processing

A

In eukaryotes, once an RNA molecule is transcribed, it is spliced and a 5’ cap and 3’ poly-adenine tail are added. This does not occur in prokaryotes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
136
Q

Portal systems

A

Circulatory routes in which blood travels through two capillary beds before returning to the heart. Examples are the hepatic, renal, and hypophyseal.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
137
Q

Foramen ovale

A

A shunt that connects the right atrium to the left atrium in order to bypass the fetal lung.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
138
Q

Nares, pharynx, larynx, trachea, bronchi, bronchioles, alveoli

A

Sequence the following structures of the respiratory tract: alveoli, trachea, larynx, nares, pharynx, bronchi, bronchioles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
139
Q

Lysosome

A

Membrane-bound vesicle that contains hydrolytic enzymes used for intracellular digestion.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
140
Q

Somatic nervous system

A

Division of the peripheral nervous system that is responsible for voluntary movement.

141
Q

Citric acid cycle

A

A series of reactions that begins when the two-carbon acetyl group from acetyl CoA combines with oxaloacetate to form citric acid. The cycle continues to release three NADH molecules, one FADH2 molecule, and one GTP molecule. It also regenerates oxaloacetate.

142
Q

Bile

A

An alkaline fluid synthesized in the liver, stored in the gall bladder, and released into the duodenum. It aids in emulsification, digestion, and absorption of fats.

143
Q

Pineal gland

A

Secretes melatonin, and is thought to help regulate sleep-wake cycles in response to external lighting cues.

144
Q

Immunoglobulins

A

Protein antibodies, each of which is produced in response to a specific foreign substance.

145
Q

Holoenzyme

A

An active enzyme containing all necessary cofactors.

146
Q

Chloroplast

A

The site of photosynthesis in plants. It contains chlorophyll, is semiautonomous, and has two cell membranes.

147
Q

Competitive inhibitor

A

Molecule that inhibits the activity of an enzyme by directly binding to the active site. It can be overcome by increasing the substrate concentration.

148
Q

Dizygotic twins

A

Results when two ova are fertilized by two different sperm. Since the two resulting embryos develop from distinct zygotes, they do not have identical alleles. Also called “fraternal”.

149
Q

Endorphins

A

Synthesized and released by the anterior pituitary, inhibit the perception of pain.

150
Q

Mitosis

A

Cell division and/or nuclear division in somatic cells that results in the daughter nucleus receiving a full complement of the organism’s genome.

151
Q

Kidney, ureter, bladder, urethra

A

Describe the path of urine from the kidney out of the body.

152
Q

Somatic cells

A

All the cells in an organism that are not reproductive.

153
Q

Lymph nodes

A

Swellings along the lymph vessels where lymph is filtered by leukocytes to remove antigens.

154
Q

Cortisol

A

A glucocorticoid that increases the blood’s glucose level.

155
Q

Glycolysis

A

A series of enzymatic reactions in the cytoplasm that convert one molecule of glucose into two molecules of pyruvate. The energy released in the process is used to produce a net yield of two ATP and two NADH molecules.

156
Q

Systole

A

The stage of the heart cycle in which the heart muscle contracts and pumps blood.

157
Q

Insulin

A

Produced and secreted by the beta cells of the pancreas, it decreases blood glucose concentrations by facilitating the uptake of clucose by muscle and adipose cells, and the conversion of glucose to glycogen in muscle and liver cells.

158
Q

Recombination frequency

A

Proportion of gametes that receive recombinant chromosomes for two different linked genes.

159
Q

Peptide hormones

A

Hydrophilic hormones incapable of permeating the cell membrane that bind to surface receptors and act through secondary messengers.

160
Q

Induction

A

The influence of a group of cells on the development of other cells.

161
Q

Afferent neurons

A

Neurons that carry information to the central nervous system from outlying tissues and sense organs.

162
Q

Fibrin

A

Protein responsible for blood clotting.

163
Q

Blood antigens

A

Proteins found on the erythrocyte cell surface. Three antigens (A, B, and Rh) are used to differentiate blood groups.

164
Q

Sarcomere

A

The structural unit of striated muscle. It is composed of thin filaments (actin) and thick filaments (myosin).

165
Q

Tricuspid valve

A

The valve located between the right atrium and the right ventricle of the heart.

166
Q

Central nervous system

A

Consists of the brain and spinal cord.

167
Q

Erythrocytes

A

The oxygen-carrying component of blood. These anarobic cells lack organelles, are packed with hemoglobin, and feature a characteristic biconcave shape.

168
Q

Hemoglobin

A

A protein found in erythrocytes made up of four polypeptide chains, each containing a heme group. It is responsible for transporting oxygen from the alveoli to the cells.

169
Q

Oxytocin

A

This hormone increases the strength of contractions during childbirth.

170
Q

DNA polymerase

A

An enzyme that polymerizes a complementary DNA strand in the 5’ to 3’ direction using a template DNA strand. It requires a primer.

171
Q

Michaelis Constant

A

A constant, Km, that is a measure of the kinetics of an enzyme reaction and that is equivalent to the concentration of substrate at which the reaction takes place at one half its maximum rate.

172
Q

Thyroid-stimulating hormone

A

Synthesized and released by the anterior pituitary, this hormone stimulates the thyroid gland to absorb iodine so that it can synthesize and secrete thyroid hormone.

173
Q

Pharynx, larynx, trachea, bronchi, bronchioles, alveoli

A

Identify the passage of air through the body during inhalation.

174
Q

Cardiac sphincter

A

A valve between the esophagus and the stomach that prevents the content of the stomach from traveling back up through the esophagus.

175
Q

Fitness (according to Darwin)

A

The ability of an organism to mate and produce fertile offspring.

176
Q

Endochondral ossification

A

The replacement of cartilage with bone.

177
Q

Parathyroid hormone

A

Synthesized and released by the parathyroid gland, it increases calcium ion concentration in the blood stimulating its release from the bones.

178
Q

Descending limb of the loop of Henle

A

Portion of the nephron permeable only to water. The filtrate becomes more concentrated as it travels through, increasing concentration of the interstitial fluid.

179
Q

Cofactor

A

A nonprotein molecule that is incorporated into an enzyme and is required for proper functioning.

180
Q

Substrate level phosphorylation

A

The transfer of a phosphate group from an organic compound to ADP. Glycolysis and the citric acid cycle utilize this to produce ATP.

181
Q

Transfer RNA

A

Class of RNA bearing an anticodon and the amino acid for the corresponding codon. Vital for translation, as it brings the amino acids to the ribosome and ensures that each codon matches up with the proper amino acid.

182
Q

Divergent evolution

A

Refers to the process whereby related groups independently develop dissimilar characteristics.

183
Q

White fibers

A

Fast-twitch muscle fibers. They are primarily anaerobic and fatigue easily.

184
Q

Cartilage

A

A firm, elastic, translucent connective tissue consisting of collagenous fibers embedded in chondrin. Produced by chondrocytes. Principal component of embryonic skeleton that calcifies into bones.

185
Q

Coenzyme

A

An organic cofactor for an enzymatic reaction (e.g., vitamin).

186
Q

Sclera

A

The white covering of the eye, made up of connective tissue.

187
Q

Lymph node

A

A swelling along a lymphatic vessel that contains phagocytic cells. Their role is to filter the lymph and remove/destroy foreign particles.

188
Q

Sister chromatids

A

After replication, each chromosome consists of these, held together at the centromere. The mitotic spindle pulls them apart.

189
Q

Schwann cells

A

Cells that produce myelin in the peripheral nervous system

190
Q

Facultative anaerobe

A

An organism that makes ATP by aerobic respiration if oxygen is present, but can switch to fermentation when oxygen is not available

191
Q

Amino acid derived hormones

A

Hormones that are synthesized from amino acids. Some act via secondary messengers, while others act in a fashion similar to steroid hormones by crossing the plasma membrane into the cell.

192
Q

Peristalsis

A

Involuntary contractions of smooth muscle that push food through the digestive tract.

193
Q

Atria

A

The two thin-walled upper chambers of the heart.

194
Q

Blood

A

Made up of plasma and cellular components, which include erythrocytes, leukocytes, and platelets

195
Q

Mechanical digestion

A

Breakdown of food particles into smaller particles through such activities as biting, chewing, and churning.

196
Q

Osteons

A

The structural units of compact bone that consist of a central canal, called the haversian canal, surrounded by a number of concentric rings of bony matrix called lamellae.

197
Q

Dihybrid cross

A

A cross between two organisms where two distinct traits are being studied.

198
Q

Repolarization

A

A process that occurs when the voltage-gated Na+ channels close and voltage-gated K+ channels open, allowing K+ to rush out of the cell.

199
Q

Interoceptors

A

Type of sensory receptor that monitors signals inside the body, such as blood pressure, pH, or the partial pressure of carbon dioxide in the blood.

200
Q

Follicle-stimulating hormone

A

Synthesized and released by the anterior pituitary, stimulates maturation of ovarian follicles in females and maturation of the seminiferous tubules and sperm production in males.

201
Q

Lytic cycle

A

Phase in viral replication in which the host cell is lysed and releases new virions.

202
Q

Active immunity

A

Immunity resulting from the production of antibodies during a previous infection or a vaccination.

203
Q

Disruptive selection

A

A type of selection that favors phenotypic extremes, leading to the expression of two or more phenotypic forms.

204
Q

Corpus callosum

A

Connects the left and right hemispheres of the brain.

205
Q

Saltatory conduction

A

A means by which action potentials jump from node to node along an axon.

206
Q

Zona pellucida

A

Inner layer of cells surrounding the oocyte. These cells are secreted by follicle cells. Penetration of these cells by a sperm forces the secondary oocyte to complete meiosis II.

207
Q

Umbilical cord

A

Connects the vasculature of the fetus to the placenta.

208
Q

Seminiferous tubules

A

Located in the testes, these are the site of sperm production.

209
Q

Monohybrid cross

A

A cross between two organisms where only one trait is being studied.

210
Q

Parallel evolution

A

The process whereby related groups independently develop similar characteristics due to analogous environmental pressures.

211
Q

Corona radiata

A

Outer layer of cells surrounding the oocyte. These cells are secreted by follicle cells.

212
Q

Action potential

A

A sharp change in the membrane potential of neurons or muscle cells caused by a change in the selective permeability to K+ and Na+ using ion-gated channels. They are all-or-none.

213
Q

Cytochrome

A

A molecular electron carrier involved in oxidative phosphorylation.

214
Q

Synovial fluid

A

A lubricant found in movable joints.

215
Q

Collecting duct

A

Portion of the nephron permeable to water and ions. As the filtrate flows down it, the filtrate concentrates.

216
Q

Mitral valve

A

A valve located between the left atrium and the left ventricle of the heart.

217
Q

Coronary veins

A

Blood vessels that transport deoxygenated blood from the heart toward the right atrium.

218
Q

B lymphocytes

A

White blood cells that are involved in humoral immunity.

219
Q

Anticodon

A

A 3-base sequence on tRNA that is complementary to the mRNA codon.

220
Q

Mitochondria

A

The site of aerobic respiration that provides the cell wit ha majority of its energy in the form of ATP. It is a semiautonomous organelles enclosed by two membranes.

221
Q

Stabilizing selection

A

A type of natural selection where the mean phenotype is favored while extreme phenotypes are eliminated.

222
Q

Plasmid

A

A small ring of extrachromosomal DNA found in bacteria. It replicates independently of the bacterial chromosome.

223
Q

Intestinal glands

A

Secrete maltase, sucrase, lactase, aminopeptidase, dipeptidase, and enterokinase into the small intestine.

224
Q

Simple diffusion

A

Passive movement of particles from a region of higher concentration to a region of lower concentration without the use of energy.

225
Q

Neurotransmitters

A

Chemical messengers released from synaptic clefs of a neuron that can bind and stimulate a postsynaptic cell.

226
Q

Vital capacity

A

The maximum volume of air that can be inhaled or exhaled by the lungs with a single breath

227
Q

Axon hillock

A

The portion of the neuron that connects the cell body to the axon. The impulses the neuron receives from all the dendrites are summed up here to determine whether an action potential will be initiated.

228
Q

Bohr effect

A

The phenomenon in which increasing the concentration of carbon dioxide reduces hemoglobin’s affinity for oxygen.

229
Q

Primary spermatocytes

A

Diploid cells that undergo meiosis I to form haploid secondary spermatocytes.

230
Q

Electron transport chain

A

A chain of cytochromes and other proteins in the inner membrane of the mitochondria that transfers electrons from NADH and FADH2 to oxygen. The energy released by the series of oxidations is used to create a proton gradient, which ATP synthase then uses to synthesize ATP.

231
Q

Mendel’s Law of Segregation

A

The postulation that there are alternate versions of genes that account for genetic variation, which are separated into two different gametes during meiosis.

232
Q

Allantois

A

The embryonic membrane that contains the growing embryo’s waste products.

233
Q

Monocyte

A

A phagocyte of foreign matter.

234
Q

Surfactant

A

A liquid produced by the lung that reduces surface tension in the alveoli.

235
Q

Filtrate

A

The material that passes from the blood vessels into the Bowman’s capsule and travels through the nephron to eventually become urine.

236
Q

Spongy bone

A

Lighter and less dense than compact bone, it consists of an interconnecting lattice of bony spicules. The cavities between the spicules contain bone marrow.

237
Q

Binary fission

A

Method of asexual reproduction by which prokaryotes divide. The circular DNA molecule replicates and then moves to opposite sides of the cell, which then divides into two daughter cells of equal size.

238
Q

Translocation

A

A form of chromosomal rearrangement in which a portion of one chromosome adds on to a nonhomologous chromosome.

239
Q

Endocytosis

A

A process in which the cell membrane invaginates, forming an intracellular vesicle containing extracellular medium.

240
Q

Endocrine glands

A

Glands that synthesize and secrete hormones into the circulatory system. Examples include the hypothalamus, pituitary, pineal, thymus, pancreas, testes, ovaries, adrenal, thyroid, and parathyroid glands.

241
Q

Ribosomal RNA

A

Class of RNA that is a structural component of ribosomes, synthesized in the nucleolus.

242
Q

Blastulation

A

The process by which a morula develops into a blastula with a fluid-filled cavity.

243
Q

Photoreceptors

A

Light-sensitive proteins

244
Q

Lymphatic system

A

A system of vessels and lymph nodes that collect interstitial fluids and return them to the circulatory system, thereby maintaining a plasma protein and fluid balance.

245
Q

Aldosterone

A

A steroid hormone produced in the adrenal cortex that increases reabsorption of sodium and water and the excretion of potassium.

246
Q

Total lung capacity

A

The maximum volume of air that the lung can hold, which includes the vital capacity and the residual volume.

247
Q

Sodium-potassium pump

A

A protein that hydrolyzes one ATP to transport three sodium ions out of the cell for every two potassium ions it transports into the cell.

248
Q

Hardy-Weinberg Equation

A

p^2 + 2pq + q^2 = 1, where p is the frequency of the dominant allele and q is the frequency of the recessive allele. It predicts the frequency of homozygous dominants, homozygous recessives, and heterozygotes.

249
Q

Leading strand

A

During DNA replication, the strand of DNA that is continuously synthesized in the 5’ to 3’ direction. The template strand is read in the 3’ to 5’ direction.

250
Q

Axial skeleton

A

The skull, vertebral column, and bones of the chest.

251
Q

Carbonic anhydrase

A

Enzyme that catalyzes the conversion of carbonic acid to carbon dioxide and water, as well as the formation of carbonic acid from carbon dioxide and water.

252
Q

Nondisjunction

A

The failure of homologous chromosomes or sister chromatids to separate properly during meiosis.

253
Q

Inferior vena cava

A

A large vein that returns deoxygenated blood from the lower body and the extremities to the right atrium f the heart.

254
Q

Glucocorticoids

A

Synthesized and released by the adrenal cortex, raise blood glucose levels while decreasing protein synthesis.

255
Q

Metaphase

A

The mitotic phase where the chromosomes line up at the equatorial plate.

256
Q

Ductus arteriosus

A

A shunt that connects the pulmonary artery to the aorta in order to bypass the fetal lung.

257
Q

Obligate intracellular parasites

A

Organisms that require a host cell to express their genes and reproduce. Viruses and some microorganisms belong to this category.

258
Q

Ovary, oviduct, uterus, cervix, vagina

A

Starting with the ovary, name the different structures of the female reproductive tract.

259
Q

Histone

A

A structural protein complexed with eukaryotic DNA to form a chromosome.

260
Q

Exons

A

Segments of coding eukaryotic mRNA that are spliced together during post-transcriptional processing

261
Q

Ductus venosus

A

A shunt that connects the umbilical vein to the inferior vena cava in order to bypass the fetal liver.

262
Q

Compact bone

A

Much more dense than spongy bone, and consists of haversian systems, or osteons.

263
Q

Villi

A

Fingerlike projections that extend out of the small intestine in order to increase surface area for maximum absorption.

264
Q

Peroxisomes

A

These make hydrogen peroxide and digest fats into smaller molecules.

265
Q

Meiosis

A

A two-phase cell division in germ cells that results in the formation of four haploid cells from one diploid cell.

266
Q

Monozygotic twins

A

Results when a single zygote splits into two embryoes. Since both embryos contain identical alleles, they are often called “identical”.

267
Q

Differentiation

A

The specialization of cells that occurs during development.

268
Q

Calcitonin

A

Hormone synthesized and released by the thyroid gland that decreases plasma calcium ion concentration.

269
Q

Chemical digestion

A

Enzymatic breakdowns of large molecules into smaller molecules.

270
Q

Peripheral nervous system

A

All neurons that are not part of the brain and spinal cord, including sensory and motor neurons. Can be further divided into the somatic and autonomic nervous systems.

271
Q

Retina

A

A thin layer of cells containing photoreceptors at the back of the eye that converts light signals into neural impulses.

272
Q

Chorion

A

Outermost extraembryonic membrane; contributes to the formation of the placenta.

273
Q

Gastrulation

A

The process by which a single-layer becomes a three-layered gastrula.

274
Q

Pineal gland

A

Secretes melatonin.

275
Q

Expiratory reserve volume

A

The amount of air that can be forcible exhaled after a normal exhalation.

276
Q

Episomes

A

Plasmids that have the ability to integrate into the host genome.

277
Q

Hyperventilation

A

An increase in the rate of inhalation. Lack of oxygen or a decrease in blood pH promotes this.

278
Q

Regulator

A

A molecule, other than the substrate, that can bind to the allosteric site of an enzyme and either increase or decrease its activity.

279
Q

Crossing over

A

The exchange of genetic material between chromosomes (usually homologous) that occurs during prophase I of meiosis. It aids in evolution and genetic diversity by unlinking otherwise linked genes.

280
Q

Analogous structures

A

Similar structures that share a common function but not similar origin.

281
Q

Dermis

A

The layer of skin beneath the epidermis that is subdivided into the papillary layer and the reticular layer. It contains the sweat glands, sense organs, blood vessels, and bulbs of hair follicles.

282
Q

Cardiac output

A

Total volume of blood the left ventricle pumps into circulation per minute. Can be increased by raising heart rate or stroke volume.

283
Q

Active transport

A

Membrane transport that utilizes energy. Unlike other methods of transport, it can move particles from a region of lower concentration to a region of higher concentration.

284
Q

Fermentation

A

Process by which the cell is able to anaerobically replenish the NAD+ used during glycolysis by oxidizing NADH.

285
Q

Translation

A

The transfer of information from an RNA molecule to a polypeptide. The three stages of polypeptide synthesis require energy and are mediated by various enzymes. mRNA is read in the 5’ to 3’ direction.

286
Q

Okazaki fragments

A

Small fragments of DNA that form the lagging strand during DNA replication

287
Q

Corpus luteum

A

Tissue that forms from the collapsed ovarian follicle after ovulation. Produces and secretes progesterone and estrogen.

288
Q

Exocrine glands

A

Glands that synthesize and secrete substances either into the digestive tract or the surface of the body through the use of ducts. Examples are the gall bladder, pancreas, and mammary glands.

289
Q

Homologous chromosomes

A

Paired chromosomes in a diploid cell that contain different alleles for the same trait at corresponding loci, although not necessarily similar functions.

290
Q

Cytosol

A

The fluid component of the cell’s cytoplasm.

291
Q

Chyme

A

Combination of partially digested food and acid that forms in the stomach.

292
Q

Intrapleural space

A

The space between the two membranes that cover the lungs.

293
Q

Induced Fit Hypothesis

A

Theory of enzyme catalysis which states that the partial binding of a substrate to an enzyme alters the structure of the enzyme so that its active site becomes complementary to the structure of the substrate, enabling binding.

294
Q

Chromatid

A

One half of a replicated chromosome. Sisters are attached by the centromere.

295
Q

Nucleolus

A

This is the region of the cell that synthesizes ribosomal RNA (rRNA)

296
Q

Gastric glands

A

Located in the stomach; secrete HCl and various enzymes when stimulated by gastrin.

297
Q

Follicle

A

A multilayered sac of cells in the ovary that protects and nourishes the developing ovum until ovulation.

298
Q

Test cross

A

A cross between an organism of undetermined genotype and another that is homozygous recessive for the trait of interest.

299
Q

Epidermis

A

The outermost layer of skin, which is composed of the following sublayers: stratum basilis, stratum spinosum, stratum granulosum, stratum lucidum, and stratum corneum. Serves as a protective barrier against microbial attack. Derived from the ectoderm.

300
Q

Adrenal cortex

A

Synthesizes and releases corticosteroids when stimulated by adrenocorticotropic hormone.

301
Q

Refractory period

A

A short period of time immediately following an action potential in which neurons or muscle cells are unresponsive to a simulus.

302
Q

Ribosome

A

The site of protein translation during protein synthesis.

303
Q

Endoplasmic reticulum

A

The structure involved in the transport of materials throughout the cell.

304
Q

Homologous structures

A

Similar structures that share a common origin.

305
Q

Wild type

A

The allele for a given trait that is most common in the population of the organism found in nature.

306
Q

Leydig cells

A

Located in the testes and secrete testosterone and other androgens.

307
Q

Apoenzyme

A

An enzyme that requires cofactors in order to become catalytically active.

308
Q

Periosteum

A

The fibrous sheath of the bone.

309
Q

Heterotroph

A

An organism that breaks down organic nutrients for energy.

310
Q

Membrane receptor

A

A protein that binds to molecules in the extracellular environment.

311
Q

Growth hormone

A

Synthesized and released by the anterior pituitary, it stimulates bone and muscle growth, as well as glucose conservation. It is inhibited by somatostatin.

312
Q

Chromatin

A

Chromosomes in their uncoiled active state.

313
Q

Thermoregulation

A

Maintenance of a constant internal body temperature.

314
Q

Noncompetitive inhibitor

A

Molecule that inhibits the activity of an enzyme by binding to a regulatory site on the enzyme, thereby changing the conformation. Increasing substrate concentration does little to counteract the inhibition.

315
Q

Transport protein

A

Helps move polar molecules and certain ions across the cell membrane.

316
Q

Glucagon

A

Produced and secreted by the alpha cells of the pancreas, it increases blood glucose concentration by promoting gluconeogenesis and glycogenolysis.

317
Q

Oxidative phosphorylation

A

The coupling of the oxidation of NADH, NADPH, and FADH2 with the phosphorylation of ADP.

318
Q

Prosthetic group

A

A tightly bound cofactor, such as heme.

319
Q

Reverse transcriptase

A

An enzyme in retroviruses that uses RNA strands as templates for synthesizing cDNA.

320
Q

Interphase

A

Phase of the cell cycle in which cell division does not take place. It includes the G1, S, and G2 phases.

321
Q

Endoderm

A

The innermost of the three primary germ layers, which gives rise to the linings of the digestive and respiratory tracts, parts of the liver, pancreas, thyroid, and bladder.

322
Q

Centrioles

A

These are involved in spindle formation during cell replication. They are found only in animal cells.

323
Q

Primary immune response

A

The initial response to a specific antigen. T and B lymphocytes are activated and specific antibodies and memory cells to the antigen are produced.

324
Q

Determinate cleavage

A

A cleavage whose future differentiation pathways are determined.

325
Q

Luteinizing hormone

A

Synthesized and released by the anterior pituitary, it stimulates ovulation and formation of the corpus luteum. It is regulated by estrogen, progesterone, and gonadotropin-releasing hormone.

326
Q

Facilitated diffusion

A

Passive movement of particles from a region of higher concentration to a region of lower concentration using carrier molecules. Does not require energy.

327
Q

T lymphocytes

A

These are involved in cell-mediated immunity. They are responsible for the body’s defense against viral and fungal infections.

328
Q

Resting potential

A

The charge difference across a cell membrane of a neuron or a muscle cell while at rest, maintained by the sodium-potassium pump.

329
Q

Introns

A

Segments of noncoding eukaryotic mRNA that are spliced out during post-transcriptional processing and are not translated into proteins.

330
Q

Antidiuretic hormone (ADH)

A

Also known as vasopressin, this hormone acts on the collecting duct of the nephron to increase water reabsorption. It is produced in the hypothalamus and stored in the posterior pituitary.

331
Q

Convergent evolution

A

Refers to the independent development of similar characteristics by non-related groups.

332
Q

Ascending limb of the loop of Henle

A

Portion of the nephron not permeable to water, As the filtrate flows through, ions are actively pumped out of the filtrate, decreasing its concentration.

333
Q

Follicular phase, ovulation, luteal phase, menstruation

A

Name the phases of the menstrual cycle

334
Q

Heterogenous nuclear RNA

A

The unprocessed precursor of mRNA

335
Q

Synapse

A

The space between the axon terminal of one neuron and the dendrite of another neuron. Neurotransmitters are released here.

336
Q

Smooth endoplasmic reticulum

A

The site of lipid synthesis and poison detoxification, and involved in protein transport within the cell.

337
Q

Proprioceptor

A

Type of sensory receptor that monitors the body’s position in space.

338
Q

Passive immunity

A

A short-lived immunity resulting from the transfer of antibodies into an individual who does not produce those antibodies.

339
Q

Ciliary muscles

A

Muscular tissue in the eye, attached to the lens, that is used to control the lens’ shape.

340
Q

Ligaments

A

Connect bone to bone and strengthen joints.

341
Q

Thyroid hormones

A

Synthesized and released by the thyroid gland, are called triiodothyronine (T3) or thyroxine (T4), stimulate cellular respiration, as well as protein and fatty acid synthesis and degradation.

342
Q

Epiglottis

A

A flap of cartilage that covers the glottis when swallowing food in order to prevent it from entering the larynx.

343
Q

Tidal volume

A

The volume of air that is normally inhaled or exhaled with each breath.

344
Q

Frequency summation

A

The process by which many successive neural impulses stimulate a neuron or a muscle until the cell being stimulated experiences an action potential or a contraction.

345
Q

Primase

A

A type of RNA polymerase that adds short segments of RNA during replication to which DNA polymerase can add nucleotides. It is essential for DNA replication.

346
Q

Allosteric enzyme

A

An enzyme with one or more additional bonding sites that change the conformation of the enzyme when occupied, usually promoting or inhibiting enzymatic activity.

347
Q

Acrosome

A

The enzyme-containing cap-like structure on the head of a sperm.

348
Q

Estrogen

A

Hormone synthesized and released by the ovaries, ovarian follicles, corpus luteum, and placenta. It stimulates the development of the female reproductive tract and secondary sexual characteristics.

349
Q

Dendrite

A

An extension of the neuron that transmits impulses toward the cell body and the axon.