AP Biology Practice Multiple Choice No Answers
A recessive trait appears in 81% of the individuals in a population that is in Hardy-Weinberg equilibrium. What percent of the population in the next generation is expected to be homozygous dominant? A. 1% B. 9% C. 18% D. 19% E. 81%
A. 1%
Which of the following describes a single population? A. A group of bacteria all of the species Bacillus subtilis B. All insects occupying three hectares of farmland C. An exact count of 315 animals in a fenced plot of land D. All the birds counted in one day by census takers in the United States E. All the animals and plants on an isolated island
A. A group of bacteria all of the species Bacillus subtilis
The products of the Krebs cycle include A. ATP, NADH, FADH2, CO2 B. ATP, NAD+, FAD, CO2 C. ATP, H2O, O2 D. ADP, CO2, H2O E. NADH, FAD+, CO2
A. ATP, NADH, FADH2, CO2
Four genes, A, B, C, and D, occur on the same chromosome. Use the following crossover frequencies to determine the order of the genes on the chromosome. Genes Crossover Frequency A and D 5% B and C 15% A and C 30% C and D 35% B and D 50% A. BCAD B. CBDA C. BACD D. CDAB E. CBAD
A. BCAD
All of the following statements about endosperm in angiosperms are correct EXCEPT: A. It forms entirely from maternal tissue. B. It has a triploid chromosome number. C. It forms from a portion of the embryo sac that contains the polar nuclei. D. It provides nutrients for the growing embryo. E. It originates from a cell that is fertilized by a sperm nucleus from a pollen grain.
A. It forms entirely from maternal tissue.
Which of the following statements about the blastopore is correct? A. It is the opening to the archenteron. B. It is the opening to the blastocoel. C. It appears in the morula stage of embryonic development. D. It forms the anus in protostomes. E. It forms the mouth in deuterostomes.
A. It is the opening to the archenteron.
Duchenne's muscular dystrophy is inherited as a sex-linked recessive allele. From whom does a male with this disease inherit the defective allele? A. Only his mother B. Only his father C. The mother or the father, but not both D. Both the mother and the father E. It is impossible to determine with certainty using only the given information.
A. Only his mother
"Primers" that initiate DNA replication consist of A. RNA nucleotides B. DNA nucleotides C. Okazaki fragments D. DNA polymerase E. nucleosomes
A. RNA nucleotides
Which of the following best describes the pattern of punctuated equilibrium in evolution? A. Speciation events occur relatively rapidly. B. Small changes that accumulate over long periods of time lead to the formation of a new species and the extinction of the old species. C. Small changes that accumulate over long periods of time lead to the divergence of one species into two or more species. D. Speciation occurs when random changes accumulate over long periods of time. E. Geographic isolation is the predominant mechanism of speciation.
A. Speciation events occur relatively rapidly.
All of the following are associated with an increase in the rate of breathing EXCEPT: A. an increase in HCO3- in the blood B. an increase in pH in the blood C. an increase in CO2 in the blood D. moving to a higher elevation E. an increase in muscular activity
A. an increase in HCO3- in the blood
A dialysis bag filled with a solution of 0.4 M sucrose and 0.4 M glucose, is placed in a beaker containing a solution of 0.2 M fructose, 0.2 M glucose and 0.2 M sucrose. The dialysis tubing will allow fructose and glucose, but not sucrose, to pass through. When the dialysis is placed into the beaker, there will be net movement of A. glucose from the dialysis bag into the beaker solution B. sucrose from the dialysis bag into the beaker solution C. fructose form the dialysis bag into the beaker solution D. glucose from the beaker solution into the dialysis bag E. sucrose from the beaker solution into the dialysis bag
A. glucose from the dialysis bag into the beaker solution
Both viruses and prokaryotes contain A. nucleic acids B. ribosomes C. a plasma membrane D. a protein coat E. a peptidoglycan wall
A. nucleic acids
Secondary growth in angiosperms A. produces woody tissue B. occurs in the apical meristem C. increases the height of a plant D. increases the length of roots E. generates root hairs
A. produces woody tissue
All of the following substances pass out of the glomerulus and into the Bowman's capsule EXCEPT: A. proteins B. glucose C. water D. urea E. salts
A. proteins
The main function of water in photophosphorylation is to A. provide electrons which are energized by light energy B. facilitate the movement of pigments into and out of the chloroplasts C. provide the necessary oxygen for the photosynthetic process D. supply the energy required for photosynthesis E. maintain the integrity of the chloroplast membranes
A. provide electrons which are energized by light energy
When oxygen is unavailable, a yeast cell can obtain ATP A. through glycolysis B. by breaking down carbon dioxide C. through oxidative phosphorylation D. by substituting carbon dioxide for processes requiring oxygen E. by breaking down water to obtain small amounts of energy
A. through glycolysis
5'-T C TI C G A C T-3' 3'-A G A G C IT G A-5' The hash marks beside the T in the DNA strand shows cleavage points for the restriction enzyme TaqI. Which of the following describes the correct DNA segments produced after treatment with the restriction enzyme? A. two fragments 5'-TCT CGACT-3' 3'-AGAGC TGA-5' B. two fragments 5'-TCTCGACT-3' and 3'-AGAGCTGA-5' C. two fragments 5'-TCTCGTCA-3' and 3'-AGAGCACT-5' D. four fragments 5'-TCT, 3'-AGAGC and CGACT-3' and TGA-5' E. four fragments 5'-TCTCG, ACT-3' and 3'-AGAGC and TGA-5'
A. two fragments 5'-TCT CGACT-3' 3'-AGAGC TGA-5'
C. A polymer made of these molecules is an energy storage molecule in cells.
All of the following are true about the molecule above EXCEPT: A. The molecule releases energy and forms ADP + P B. High energy bonds are located between the phosphate bonds. C. A polymer made of these molecules is an energy storage molecule in cells. D. The molecule can provide energy form muscle contraction. E. Part of this molecule describes the structure of an RNA molecule.
A man and a woman have blood types A and B, respectively. Both have one parent with O blood type. What is the probability that the man and woman have a child with O blood type? A. 0% B. 25% C. 50% D. 75% E. 100%
B. 25%
Hemophilia is inherited as a sex-linked recessive trait. If a woman whose father has hemophilia marries a man without hemophilia, what is the probability that their child will be a boy with hemophilia. A. 0% B. 25% C. 50% D. 75% E. 100%
B. 25%
A cell has a diploid chromosome number of 8. How many chromosomes would be present in each daughter cell at the end of telophase II of meiosis? A. 2 B. 4 C. 8 D. 16 E. 32
B. 4
If A represents a dominant allele and a represents the recessive allele, what are the genotypes of parents that produce 300 progeny with the dominant trait and 100 progeny with the recessive trait? A. AA X AA B. AA X Aa C. AA X aa D. Aa X aa E. Aa X Aa
B. AA X Aa
Which of the following transmits nerve impulses between neurons? A. Cholinesterase B. Acetylcholine C. K+ D. Ca2+ E. Synaptonemal complex
B. Acetylcholine
Which of the following is MOST responsible for the movement of water up a tall tree? A. Adhesion B. Capillary action C. Guttation D. Osmosis E. Sunlight
B. Capillary action
Forms the morula A. Neurulation B. Cleavage C. Fertilization D. Organogenesis E. Gastrulation
B. Cleavage
Which of the following structures are found in both prokaryotic and eukaryotic cells? A. Cell membrane and chloroplasts B. DNA and ribosomes C. Cell walls and a nuclear envelope D. Flagella and endoplasmic reticulum E. Golgi complex and mitochondria
B. DNA and ribosomes
All of the following occur for the contraction of a motor muscle EXCEPT: A. The sarcoplasmic reticulum releases Ca2+ B. The actin cross-bridges attach to the myosin filaments. C. An action potential travels along the T-tubules. D. ATP is available. E. A neurotransmitter diffuses across the neuromusclar junction.
B. The actin cross-bridges attach to the myosin filaments.
In most flowering plants, photosynthesis occurs in leaves primarily in A. cells in the spongy mesophyll B. cells of the palisade mesophyll C. epidermal cells D. cells of the vascular tissue E. bundle sheath cells
B. cells of the palisade mesophyll
Clown fish hide among the tentacles of sea anemones. Unlike their predators, clown fish are immune to the stinging tentacles. Thus, clown fish are protected within the sea anemones. The sea anemones are neither helped nor harmed by the presence of the clown fish. The relationship between the clown fish and the sea anemone is a example of A. competition B. commensalism C. mutualism D. parasitism E. predation
B. commensalism
Mature xylem tissue is characterized by A. companion cells B. dead cells C. plasmodesmata D. sieve-tube members E. the secretion of a cuticle
B. dead cells
DNA replication occurs during A. anaphase B. interphase C. metaphase D. prophase E. telophase
B. interphase
The frequency of individuals better able to survive in a new habitat increases in a population over time. The best explanation for this is A. mutation B. natural selection C. genetic drift D. gene flow E. the founder effect
B. natural selection
Aphids are insects that insert their needlelike mouth parts into plants. Sometimes, fluid from the plant tissues passes entirely through the digestive tract of the aphid and emerges as a small droplet at its posterior end. The source of this liquid is probably A. epidermal cells B. phloem cells C. tracheids D. vessels E. xylem cells
B. phloem cells
The primary function of progesterone in the menstrual cycle is to A. stimulate development of the egg B. stimulate development of the endometrium C. stimulate development of the corpus leuteum D. stimulate development of the follicle E. trigger ovulation
B. stimulate development of the endometrium
Two sympatric species of pine trees release their pollen during different months. This is an example of A. habitat isolation B. temporal isolation C. behavioral isolation D. mechanical isolation E. geographic isolation
B. temporal isolation
A bacteriophage is a A. bacterium that attacks viruses B. virus that attacks bacteria C. bacterium that attacks eukaryotic cells D. parasitic bacterium E. parasitic eukaryotic cell
B. virus that attacks bacteria
Which of the following cellular bodies contains enzymes for breaking down macromolecules? A. Desmosomes B. Lysosomes C. Nucleosomes D. Peroxisomes E. Ribosomes
B. virus that attacks bacteria
The size of a population of mice on an isolated island has remained constant for 50 years. What is the average number of offspring that each breeding pair produce during their lifetime that survive to reproductive maturity and reproduce? A. 0 B. 1 C. 2 D. 10 to 20 E. More than 20
C. 2
Two species of finches living on separate islands have beaks of the same size. On one island where both species live together, beak sizes are different. A. Genetic drift B. Coevolution C. Character displacement D. Sexual selection E. Kin selection
C. Character displacement
Which of the following is produced by the corpus luteum? A. Progesterone and estrogen B. Progesterone ad follicle stimulating hormone C. Follicle stimulating hormone and luteinizing hormone D. Estrogen and luteinizing hormone E. Progesterone and gonadotropin releasing hormone
C. Follicle stimulating hormone and luteinizing hormone
A hormone involved in the maintenance of blood sugar levels. A. Cellulose B. Glycogen C. Glucagon D. Guanine E. Phospholipid
C. Glucagon
A body plan with radial symmetry is found in which of the following groups? A. Flatworms B. Roundworms C. Hyrdozoans and Jellyfish D. Rotifers E. Sponges
C. Hyrdozoans and Jellyfish
Which of the following is correct about diastolic blood pressure? A. It is generated by contraction of the ventricles. B. It is measured in the veins. C. It is the pressure determined using a sphygmomanomter that is recorded when the sounds of Korotkoff disappear. D. It is measured in cubic centimeters per second (cc/sec). E. In increases as an individual becomes more physically fit.
C. It is the pressure determined using a sphygmomanomter that is recorded when the sounds of Korotkoff disappear.
What is the relationship between the migration distance and DNA fragment size in a gel electrophoresis? A. Migration distance in independent of DNA fragment size. B. Longer DNA fragments travel a greater distance than shorter fragments. C. Migration distance is inversely proportional to the fragment size. D. Migration distance is directly proportional to the fragment size. E. The heavier the fragment size, the greater the migration distance.
C. Migration distance is inversely proportional to the fragment size.
Kangaroo rats live in desert habitats. Which of the following physiological or behavioral adaptations increases their survival in this hot and dry environment? A. Frequent drinking B. Frequent urination C. Nephrons with long loops of Henle D. Numerous sweat glands in their skin E. Diurnal activity
C. Nephrons with long loops of Henle
When ATP is produced in mitochondria, all of the following occur EXCEPT: A. Water is formed from O2, electrons, and H+ B. NADH is converted to NAD+ and H+ C. Protons are pumped out of the mitochondria D. An electrochemical gradient is established across mitochondrial membranes. E. A pH gradient is established across mitochondrial membranes.
C. Protons are pumped out of the mitochondria
In peas, a dominant allele (R) produces a round pea shape, while a recessive allele (r) produces a wrinkled shape. At a second locus on a different chromosome, a dominant allele (Y) produces yellow colored seeds, while a recessive allele (y) produces green-colored seeds. If a cross between two pea plants produces 1/4 wrinkled seeds and 1/2 yellow seeds, which of the following represents the parental genotypes? A. RRYY X rryy B. RrYy X rryy C. RrYy X Rryy D. RrYy X RrYy E. Rryy X Rryy
C. RrYy X Rryy
In C3 plants , the enzyme that incorporates CO2 into an organic molecule is A. helicase B. PEP carboxylase C. RuBP carboxylase D. carboxypeptidase E. pyruvate decarboxylase
C. RuBP carboxylase
Which of the following is true about the vascular cambium? A. The vascular cambium transports sugars. B. The vascular cambium transports water and solutes. C. Secondary growth of the vascular cambium produces xylem and phloem cells. D. Cells of the vascular cambium are connected by plasmodesmata. E. The vascular cambium constitutes the sapwood of the plant.
C. Secondary growth of the vascular cambium produces xylem and phloem cells.
Food storage in seeds occurs in the A. embryo B. coleoptile C. cotyledon D. germ E. plumule
C. cotyledon
Elongation of cells in shoot tops of plants is promoted by A. abscisic acid B. carotenes C. cytokinins D. ethylene E. indoleacetic acid
C. cytokinins
A young gosling follows its mother soon after birth. If a human raises the gosling from birth, the young gosling follows a human. If no animate object is nearby at birth, the gosling fails to follow its mother or a human if either are introduced several days after birth. This behavior can best be described as A. insight B. associative learning C. imprinting D. fixed action pattern E. trial-and-error learning
C. imprinting
Which of the following carries the code that determines the sequence of monomers in a protein? A. rRNA B. tRNA C. mRNA D. The large ribosome subunit E. DNA polymerase
C. mRNA
All of the following can be found in plasma membranes of eukaryotes EXCEPT: A. cellulose B. phospholipids C. oligosaccharides D. proteins E. cholesterol molecules
C. oligosaccharides
An experiment to replicate the production of organic molecules in an environment similar to earth's environment before life appeared would require all of the following EXCEPT: A. ammonia gas B. carbon dioxide gas C. oxygen gas D. ultraviolet light E. water vapor
C. oxygen gas
During cellular respiration, ATP is generated by all of the following EXCEPT: A glycolysis B. oxidative phosphorylation C. the Calvin-Benson cycle D. biochemical pathways occurring in the cytoplasm E. biochemical pathways occurring in the mitochondria
C. the Calvin-Benson cycle
A cell has a diploid chromosome number of 8. How many chromosomes would be present in a cell at anaphase of mitosis? A. 2 B. 4 C. 8 D. 16 E. 32
D. 16
A cell contains four pairs of homologous chromosomes represented by A1/A2 B1/B2 C1/C2 D1/D2. Which of the following represents the chromosome makeup of a gamete derived from this cell? A. A1A2B1B2 C1C2D1D2 B. B1B1C1D1 C. A1A2B1B2 D. A1B2C2D2 E. A1C1C2D1
D. A1B2C2D2
Turner Syndrome occurs in humans whose cells are missing the Y chromosome. All of the following are true about Turner Syndrome EXCEPT: A. A Turner syndrome zygote results when a sperm missing a Y chromosome fertilizes a normal egg. B. A Turner syndrome zygote results when a normal sperm bearing an X chromosome fertilizes an egg missing an X chromosome. C. During meiosis, nondisjunction occurs to produce one of the gametes used to form the Turner syndrome zygote. D. Barr bodies form in the nuclei of Turner syndrome individuals. E. The zygote has 45 chromosomes.
D. Barr bodies form in the nuclei of Turner syndrome individuals.
Which of the following is an anabolic reaction? A. ATP + H2O --->ADP + P B. Cellular respiration C. Starch + n (H2O) --> n(C6H12O6) D. CO2 + H2O --> C6H12O6 + O2 E. Glycolysis
D. CO2 + H2O --> C6H12O6 + O2
Which of the following organisms would most likely be located at the bottom of the pyramid of biomass? A. Squid B. Crustaceans C. Seal D. Diatoms E. Sharks
D. Diatoms
A change in the DNA sequence form ATCAGTC to ATCAAGTC
D. Frameshift mutation
A nitrogen base found in DNA. A. Cellulose B. Glycogen C. Glucagon D. Guanine E. Phospholipid
D. Guanine
The development of seeds is not protected inside an ovary. A. Angiosperms B. Ferns C. Green algae D. Gymnosperms E. Mosses
D. Gymnosperms
A dialysis bag filled with a solution of 0.4 M sucrose and 0.4 M glucose, is placed in a beaker containing a solution of 0.2 M fructose, 0.2 M glucose and 0.2 M sucrose. The dialysis tubing will allow fructose and glucose, but not sucrose, to pass through. Which of the following processes occurs during the 24-hour period after the dialysis bag is put into the beaker? A. Diffusion and plasmolysis B. Facilitated diffusion and osmosis C. Osmosis and active transport D. Osmosis and dialysis E. Osmosis and plasmolysis
D. Osmosis and dialysis
Photoperiodism is regulated by which of the following substances? A. Anthocyanin B. Chlorophyll C. Gibberellins D. Phytochrome E. Xanthophyll
D. Phytochrome
Which of the following lack a true coelom? A. Earthworms B. Mammals C. Mollusks D. Roundworms E. Sea stars and sea urchins
D. Roundworms
In many animal species, males and females look different A. Genetic drift B. Coevolution C. Character displacement D. Sexual selection E. Kin selection
D. Sexual selection
In an effort to clone a human protein, material from a human cell is introduced into bacteria. Which of the following human materials are needed for this procedure? A. The segment of DNA coding for the protein's mRNA transcript. B. The rRNA and tRNA used during translation of the protein. C. The protein's mRNA transcript found in the nucleus. D. The protein's mRNA found in the cytoplasm. E. The introns removed from the protein's unprocessed mRNA transcript
D. The protein's mRNA found in the cytoplasm.
The lac operon A. is found in eukaryotic cells B. codes for the sequence of amino acids in lactase C. regulates the translation of mRNA D. regulates transcription by turning on or off the production of a repressor protein E. regulates DNA replication by turning on or off the production of an inducer protein
D. regulates transcription by turning on or off the production of a repressor protein
Over a period of 100 years, a clear mountain lake is transformed into a meadow. During the transition, various communities inhabit the area. Each community is replaced by a new community and after a period of time. The ecological process described in the above paragraph is an example of A. carrying capacity B. density-dependent limiting factors C. denisty-independent limiting factors D. succession E. biotic potential
D. succession
All of the following are end products of the light-dependent reactions of photosynthesis EXCEPT: A. NADPH B. ATP C. O2 D. H+ E. C6H12O6
E. C6H12O6
A transcription of the DNA sequence CCCGGAATT would produce which of the following sequences in mRNA? A. CCCGGAATT B. GGGCCTTAA C. AAATTCCGG D. UUUAACCAA E. GGGCCUUAA
E. GGGCCUUAA
Begins at the primitive streak A. Neurulation B. Cleavage C. Fertilization D. Organogenesis E. Gastrulation
E. Gastrulation
Begins the formation of the three primary germ layers A. Neurulation B. Cleavage C. Fertilization D. Organogenesis E. Gastrulation
E. Gastrulation
Which of the following is the dominant reaction as blood flows through the pulmonary capillaries? (Hb=hemoglobin) A. H2CO3 --> H+ + HCO3 B. H2O + CO2 --> H2CO3 C. Hb + 4CO2 --> Hb (CO2)4 D. Hb(O2)4 --> Hb + 4O2 E. Hb + 4O2 --> Hb(O2)4
E. Hb + 4O2 --> Hb(O2)4
A change in the gene sequence from ABCDEF to ADCBEF A. Polyploidy B. Deletion C. Substitution D. Frameshift mutation E. Inversion
E. Inversion
In an ant colony, sterile sisters are workers who maintain the nest and provide care for their reproducing mother, the queen. A. Genetic drift B. Coevolution C. Character displacement D. Sexual selection E. Kin selection
E. Kin selection
Which of the following is a function of the Golgi complex? A. Protein synthesis B. Ribosome synthesis C. DNA replication D. Ca2+ storage in muscle cells E. Modifying and packaging of proteins and lipids into vesicles
E. Modifying and packaging of proteins and lipids into vesicles
The gametophyte generation is the dominant stage of the life cycle, and the sporophyte generation remains attached to the gametophyte. A. Angiosperms B. Ferns C. Green algae D. Gymnosperms E. Mosses
E. Mosses
Over a period of 100 years, a clear mountain lake is transformed into a meadow. During the transition, various communities inhabit the area. Each community is replaced by a new community and after a period of time. Which of the following statements best explains why a new community is able to replace the resident community? A. Species in the resident community die from old age. B. Species in the resident community die from disease that eventually appears. C. Given enough time, new species able to compete for the same resources as the resident species arrive. D. Species extinction is inevitable. E. The biotic and abiotic characteristics of the habitat change due to the influence of the resident community.
E. The biotic and abiotic characteristics of the habitat change due to the influence of the resident community.
Which of the following statements concerning photosynthetic pigments (chlorophyll a and b, carotenes, and xanthophylls) is correct? A. The Rf values obtained from a chromatographic analysis are the same for these molecules. B. The wavelength of light absorbed is the same for these molecules. C. The molecules have the same molecular weight. D. The molecules have the same solubility in chromatography solvents. E. The molecules absorb energy by boosting electrons to higher energy orbitals.
E. The molecules absorb energy by boosting electrons to higher energy orbitals.
Which of the following correctly describes plasmids? A. They are composed only of RNA. B. They are composed of RNA and protein. C. They are DNA segments in the chromosomes of bacteria. D. They are the DNA cores of viruses. E. They can be transferred between bacteria during conjugation.
E. They can be transferred between bacteria during conjugation.
All of the following characteristics are found in the phylum Arthropoda EXCEPT: A. body segmentation B. jointed appendages C. an exoskeleton made with chitin D. a true coelom E. a closed circulatory system
E. a closed circulatory system
A severe storm forms a new rive that divides a population of mice. After 500 years, a drought causes the rive to dry up, allowing the two populations of mice to mix. Mating between mice from the two populations does not yield any offspring. This is an example of A. hybridization B. adaptive radiation C. balanced polymorphism D. sympatric speciation E. allopatric speciation
E. allopatric speciation
Adenine, a nitrogen base, is found in all of the following EXCEPT: A. RNA B. DNA C. ATP D. cAMP E. amino acids
E. amino acids
All of the following are effective in lowering body temperature in mammals EXCEPT: A. large ears B. sweating C. panting D. decreased muscular activity E. decreased blood flow to extremities
E. decreased blood flow to extremities
A plant the produces fruit, has leaves with veins branching to form a netlike pattern, and has vascular bundles in stems arranged in a circle is most likely a A. corn plant B. fern C. moss D. pea plant E. pine
E. pine
The function of the notochord is to A. form the placenta in placental mammals B. form the vertebrae in higher chordates C. form the central nervous system in higher chordates D. form the umbilical cord in placental mammals E. provide body support in lower chordates
E. provide body support in lower chordates
A function of the allantois is to A. form the amniotic cavity B. fuse with the endometrium and form the placenta C. develop into the nervous system D. store food for use by the developing embryo E. store or dispose of wastes from the developing embryo
E. store or dispose of wastes from the developing embryo
A dialysis bag filled with a solution of 0.4 M sucrose and 0.4 M glucose, is placed in a beaker containing a solution of 0.2 M fructose, 0.2 M glucose and 0.2 M sucrose. The dialysis tubing will allow fructose and glucose, but not sucrose, to pass through. After the dialysis bag is allowed to remain in the beaker for 24 hours. A. the solution inside the dialysis bag will be hypotonic relative to the solution outside the bag B. the concentration inside and outside the dialysis bag will be equal for each solute C. the volume of water in the beaker will increase D. the dialysis bag will become flaccid E. the dialysis bag will become turgid
E. the dialysis bag will become turgid
D. memory cells
If the immune responses at day 5 and day 30 are reactions to the same substance, the likely source of antibodies at day 30 are A. cytotoxic T cells B. erythrocytes C. interleukins D. memory cells E. macrophages
C. an antigen
The action of the immune system at day 5 is most likely in response to the introduction of A. an antibiotic B. an antibody C. an antigen D. an immunoglobulin E. a major histocompatibility complex molecule
A. an allele for the disorder only from her mother
The best explanation for the inheritance of the disorder in the female in generation 3 is that she received A. an allele for the disorder only from her mother B. an allele for the disorder only from there father C. alleles for the disorder from both parents D. two alleles for the disorder from her mother E. two alleles for the disorder from her father
A. an autosomal dominant allele
The disorder illustrated in the pedigree is probably inherited as A. an autosomal dominant allele B. an autosomal recessive allele C. an X-linked dominant allele D. an X-linked recessive allele E. a Y-linked dominant allele
A. B cells
The immune response indicated at day 5 in the graph is most likely produced by the action of A. B cells B. T cells C. cytotoxic T cells D. helper T cells E. macrophages
C. C
Which letter refers to the net movement of K+ out of the neuron? A. A B. B C. C D. D E. E
D. D
Which letter refers to the refractory period? A. A B. B C. C D. D E. E
E. E
Which letter refers to the resting potential of the neuron? A. A B. B C. C D. D E. E
C. 50%
Which of the following is the probability of the disorder appearing in the next offspring from from affected parent? A. 0% B. 25% C. 50% D. 75% E. 100%