CST review
5' G T A _ _ _ A A 3' 3' C A T G C A T T 5' a repair enzyme would replace them with
CGT
5' ATCAGCGCTGGC 3' how many amino acids ^ are coded for by this segment?
4
which of the following base pair sequences could be produced in DNA replication?
5' AGTCAT 3' 3' TCAGTA 5'
based only on the sex chromosomes in typical human egg and sperm cells at fertilization, the probability of producing a female is
50%
in certain breeds of dogs, deafness is due to a recessive allele (d) of a particular gene, and normal hearing is due to its dominant allele (D). what percentage of the offspring of a normal heterozygous (Dd) dog and a deaf dog (dd) would be expected to have normal hearing?
50%
which cellular organelle is responsible for packaging the proteins that the cel secrets?
Golgi apparatus
in fruit flies, the gene for red eyes (R) is dominant and the gene for sepia eyes (r) is recessive. what are the possible combinations of genes in the offspring of two red- eyed heterozygous flies (Rr)
RR, Rr, and rr only
if a corn plant has a genotype of Ttyy, what are the possible genetic combinations that could be present in a single grain of pollen from the plant?
Ty, ty
a base sequence is shown below ACAGTGC how would the base sequence be coded in mRNA?
UGUCACG
a scientist puts nucleotide chains of UUUUUU in a test tube under conditions allowing protein synthesis. soon the test tube is full of polypeptide chains composed of only the amino acid phenylalanine. what does this experiment indicate?
UUU codes for the amino acid phenylalanine
when mount St. Helens volcano erupted, the blast covered much of the surroundings area with ash. based on the diagram above which list shows the sequence of secondary succession that followed that eruption?
Z, X, Y, W
there are 2 petri dishes with clear cornstarch gel, 1) is marked with an X with a cotton swab and the other dish 2) there was saliva on the swab before marking the X. dish 1 turned blue while 2 everything was blue except the x. what is the most probable explanation of the clear X?
a chemical in the saliva broke down the starch in the gel
grasses --> crickets --> field mice --> hawks for the food chain shown, which of the following changes would have the most severe consequences?
a drastic decrease in rainfall, causing drought
one of the human disease is caused by a change in one codon in a gene from GAA to GUA. this disease is the result of
a mutation
mutations within a DNA sequence are
a natural process the produce genetic diversity
sweat and sin secretions contain a mixture of molecules that kills or limits the growth of many types of microbes. this control of microbes is an example of
a nonspecific defense against infection
_______ is surrounded by a rigid coat of cellulose has DNA contains mitochondria and chloroplasts
a plant cell
earth has undergone some catastrophic changes from time to time. which of these most likely explains why life on earth continued following these catastrophes?
a wide diversity of species existed
the fight or flight response includes greater heart output and a rise in blood pressure. this response is due to
adrenaline secreted by the adrenalin glands
fur color in cats is controlled by an autosomal gene that can occur in the dominant form (B) or the recessive form (b). the length of the cats fur is controlled by another autosomal gene that occurs in the dominant form (S), or the recessive form (s). the following genotypes were found in a male cat and a female cat. which is true of the phenotype of offspring from the parents?
all offspring will have short hair fur
there are many different enzymes located in the cytoplasm of a single cell. how is a specific enzyme able to catalyze a specific reaction?
an enzyme binds to a specific substrate for the reaction catalyzed
which of these best illustrates natural selection?
an organism with favorable genetic variations will tend to survive and breed successfully
some snake venoms are harmful because they contain enzymes that destroy blood cells of tissues. the damage caused by such snakebite could best be slowed by
applying ice to the bite area
in a carrier there is a rare inherited condition that causes the death of the chicks before hatching. in order for this disease to be passed from generation to generation there must be parent birds that
are heterozygous for the disease
individuals with HIV sometimes contract a pneumonia infection that is rare in the rest of the population because people with HIV
are unable to fight off the pneumonia causing organisms
complete burning of plant material returns carbon primarily to the the
atmosphere
how do human diseases caused by bacteria and diseases caused by viruses react to antibiotics?
bacterial diseases respond to antibiotics; viral diseases do not
if a paleontologist finds fossils of many different species existing in the same area at approximately the same time, the paleontologist can conclude that the ecosystem in this area had a high degree of
biological diversity
the chart shows four alleles at the same locus that affects rabbits' coat color. each alle is dominant to the ones below it. rabbits with an albino or himalayan coat are mosre susceptible to predators. which of the following genotypes will produce a rabbit that is least likely to survive?
c^h c
the clear protein of an egg white becomes opaque and firm when cooked because the heat
changed the protein structure
the homeostatic mechanism in humans that regulate blood pH depends ont he feedback of information from
chemical receptors
which molecule in plant cells first captures the radiant energy from sunlight?
chlorophyll
which of these would have the least effect on natural selection in a subspecies of giraffes that is geographically isolated fro other subspecies of giraffes?
chromosome number
carbon dioxide is produced as cells break down nutrients for energy. which of the following pairs of systems would participate in removing the carbon dioxide from the body?
circulatory and respiratory
the respiratory system depends on the nervous system for signals to
coordinate muscles controlling breathing
the diagran above shows the homologous chromosomes during prophase 1 of meiosis. which of the following correctly describes the process being illustrated?
crossing over in which alleles are exchanged
epithelial cell from a tadpole intestine --> nucleus from tadpole cell is implanted in enucleated egg --> egg from another frog. nucleus has been destroyed. egg develops into frog with the same characteristics of original nucleus donating tadpole. which is best demonstrated by the experiment above?
differentiated cells contain a complete set of genes
maltose can be broken down into glucose molecules by the enzymes maltase. which of the following would slow the reaction rate?
diluting with water
semi- conservative replication of DNA refers to the idea that?
each half of the original DNA molecule is joined with a new complementary DNA strand
which of these organisms are most helpful in preventing earth from being covered with the bodies of dead organisms
fungi and bacteria
the bacterium agrobacterium tumefaciens infects plants , and a portion of its DNA is inseted to the plants chromosomes. this causes the plant o produce gell cells, which manufactures amino acids that the bacterium uses as food. this process is natural example of ?
genetic manipulation
a small portion of a population that is geographically isolated from the rest of the population runs the risk o decreased
genetic variation
fossil evidence suggests that a number of member of one fish species from an ancient lake in death valley, california, became several isolated species. each of these new species lived in a different pond.. which of the following best explains the cause of the speciation
geographic isolation
which of these organisms would most likely be found at the bottom of a biomass pyramid?
green algae
mendel hypothesized that reproductive ce;;s have only one factor for each inherited trait. this hypothesis is supported by the observation that
haploid cells are produced by meiosis
eukaryotic cells are differentiated from prokaryotic cells because eukaryotic cells
have nuclei
in most stable freshwater environments, population of Daphnia are almost entirely female and reproductive asexually. however males are observed in low oxygen environments or when food is scarce. based on these observations, a researcher suggets that male Daphnia develop in response to unfavorable environmental conditions. this is an example of a
hypothesis
fromm 1990 to 2000, the population has
increased
what is the greatest danger to a patient who has had a damage to the skin?
infections in uncovered tissues
a species of finch has been studies at galapagos island. since the island is small, the lineage of every bird for several generations is known. this allows a family groups have survived and others have died out. the groups that survive probably have
inherited some advantages variations
genetic engineering has produced goats whose milk contains proteins that can be used as medicines. this effect was produced by?
inserting foreign genes into fertilized goat eggs
which of the following best describes meiosis?
it occurs only in cells in the reproductive structures of the organism
how did the evidence affect the work of Watson and Crick?
it was used to determine the physical structure of DNA
a small population of chimpanzees lives in a habitat that undergoes no change for a long period. how will genetic drift probably affect the population?
it will reduce genetic diversity
after a volcanic has covered an area with lava, which of the following is the most likely order of succession in the repopulation of the area?
lichens ---? grasses ---> shrubs ---> trees
the first stage of photosynthesis in a chloroplasts is
light dependent
which group demonstrated the greatest bio diversity during the cretaceous period?
lizards
what causes tomatoes to ripen much more slowly on a refrigerator then they do if left on a table at room temperature?
low temperatures reduce the action of ripening enzymes
a strand of mRNA containing the repeating sequence AAGAAGAAGAAG could code for which of the following amino acids?
lys-lys-lys-lys
a computer model of cellular mitosis can simulate the aspects of cellular division quite well. however microscopic observation of actual cellular mitosis can improve understanding because actual observations
may reveal greater unknown complexities
a cellular process the occurs in organisms
meiosis
a cell from heart muscle would probably have an unusually high proportion of
mitochondria
in aerobic respiration, the krebs cycle (citric acid cycle) takes place in
mitochondria
which of the following sequences represents chromosomes number during fertilization?
n + n --> 2n
a population f termites initially consists of darkly colored and brightly colored members. after several generations the termite population consists almost entirely of darkly colored members because the brightly colored termites are easier for a predatory species of insectivores to locare. this situation is an example pf?
natural selection
a healthy individual is a carrier of a lethal allele but is unaffected by it. what is the probable genotype of this individual?
one recessive lethal allele and one dominant lethal allele
the Sabin vaccine is a liquid containing weakened polio viruses. vaccinated individuals become protected against polio because the weakened viruses
promote production of antibiotics
striking the tendon just below the kneecap causes the low leg to jerk. moving an object quickly toward the face can cause the eyes to blink shut. these are examples of
reflex reactions
the cell membrane of red blood cell will allow water, oxygen, carbon dioxide, and glucose to pass through. because other substances are blocked from entering, this membrane is called
semi permeable
a signal that the bladder us full is sent to the central nervous system by
sensory neurons
although there are a limited number of amino acids, many different types of proteins exist because the
sequence and number of amino acids is different
which of these organisms would most likely be found at the top of an energy pyramid?
sharks
which of the following is a function to the nervous system
signaling muscle tissue to contract
injecting a person with a killed bacteria vaccine can protect that individual form a disease because the proteins of the killed bacteria
stimulate the production of antibiotics which can be manufactured later in response to infection
scientist found that, over a period of 200 years, a mountain pond was transformed into a meadow. during that time, several communities were replaced by different communities. which of these best explains why new communities were able to replace older communities?
the abiotic characteristics of the habitat changed
if a human baby boy inherits a recessive allele from his mother, in which circumstance would be most likely show the trait coded for by the recessive allele?
the allele is on the X chromosome
which of the following statements correctly describes meiosis
the cells produced at the end of meiosis contain half the number of chromosomes as the parent cell
which of the following is the best explanation for why the chromosome number is an even number of these organisms?
the diploid chromosome number represents pairs of chromosomes, one from each parent, so its always an even number
a genetic disorder due to a recessive allele (a) is lethal in homozygous individuals (aa), whereas heterozygous individuals (Aa) have no symptoms. based on this info, which of the following is likely to result?
the disorder will be maintained in the population through the reproduction of heterozygous
which of these would most likely cause a mutation?
the insertion of nucleotide into DNA
a single species of squirrel evolved over time into two species, each on opposite sides of the Grand Canyon. this change was most likely due to
the isolation of two groups
in a pond the primary producer is green alga, the primary consumer is crustacean; the secondary consumer is a small fish; tertiary consumer is a large fish. what changes can be expected in the pond if the daphnia are killed with pesticides?
the smallmouth bass population will die
which information was most important to the development of genetic engineering techniques?
the structure of DNA molecule
rabbits introduces into australian over 100 years ago have become a serious pest to farmers. rabbit populations increased so much that they displaced many native species of plant eaters. what is the most logical explantation for their increased numbers?
there are few effective predators
which of the following best describes the use of population models in biology
they can help predict outcomes
which of these secretes a hormone that regulate the rate of metabolism of the body?
thyroid
the plasma membrane of a cell consists of
two layer lipids organized with the non-polar trails forming the interior of the membrane
two students were testing the amount of fertilizer that would best promote the growth of strawberries in a garden. which would be an unavoidable source of experimental error?
variation in the strawberry plants
which of the following require a host cell because they are not able to make proteins on their own?
viruses
in order for the body to maintain homeostasis, the chemical decomposition of food to produce energy mist be followed by
waste removal