Biology CST

50%

Based only on the sex chromosomes in typical human egg and sperm cells at fertilization, the probability of producing a female is

circulatory and respiratory

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?

lys-lys-lys-lys

Codons Found in Messenger RNA A strand of mRNA containing the repeating sequence AAGAAGAAGAAG could code for which of the following amino acid sequences?C the movement of transfer RNA out of the nucleus

atmosphere

Complete burning of plant material returns carbon primarily to the

4

5' ATCAGCGCTGGC 3' The above sequence of DNA is part of a gene. How many amino acids are coded for by this segment?

CGT

5' G T A _ _ _ A A 3' 3' C A T G C A T T 5' This segment of DNA has undergone a mutation in which three nucleotides have been deleted. A repair enzyme would replace them with

UGUCACG

A base sequence is shown below. ACAGTGC How would the base sequence be coded on mRNA?

mitochondria

A cell from heart muscle would probably have an unusually high proportion of

may reveal greater unknown complexities

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

a drastic decrease in rainfall, causing drought

A food chain is shown below. Grasses-Crickets-Field-Mice-Hawks For the food chain shown, which of the following changes would have the most severe consequences?

The disorder will be maintained in the population through the reproduction of heterozygotes.

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 information, which of the following is likely to result?

one recessive lethal allele and one dominant normal allele

A healthy individual is a carrier of a lethal allele but is unaffected by it. What is the probable genotype of this individual?

natural selection.

A population of 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 locate. This situation is an example of

UUU codes for the amino acid phenylalanine.

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?

sensory neurons

A signal that the bladder is full is sent to the central nervous system by

the isolation of the two groups.

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

It will reduce genetic diversity.

A small population of chimpanzees lives in a habitat that undergoes no changes for a long period. How will genetic drift probably affect this population?

genetic variation.

A small portion of a population that is geographically isolated from the rest of the population runs the risk of decreased

inherited some advantageous variations.

A species of finch has been studied on one of the geographically isolated Galapagos Islands for many years. Since the island is small, the lineage of every bird for several generations is known. This allows a family tree of each bird to be developed. Some family groups have survived and others have died out. The groups that survive probably have

a chemical in the saliva broke down the starch in the gel.

A student filled two Petri dishes with a clear cornstarch gel, then marked the letter "X" invisibly onto the gel in Petri dish 1 with a damp cotton swab. He then placed saliva from his mouth onto a second cotton swab and used that swab to mark the letter "X" invisibly onto the gel in Petri dish 2. Fifteen minutes later, he rinsed both Petri dishes with a dilute solution of iodine to indicate the presence of starch. The surface of Petri dish 1 turned completely blue, indicating starch. Most of the surface of Petri dish 2 was blue, except the letter "X" was clear, as shown above. The most probable explanation of the clear "X" is that

lichens-grasses-shrubs-trees

After a volcanic eruption has covered an area with lava, which of the following is the most likely order of succession in the repopulation of the area?

C sequence and number of amino acids is different.

Although there are a limited number of amino acids, many different types of proteins exist because the

A wide diversity of species existed.

Earth has undergone some catastrophic changes from time to time. Which of these most likely explains why life on Earth continued following these catastrophes?

have nuclei

Eukaryotic cells are differentiated from prokaryotic cells because eukaryotic cells

geographic isolation

Fossil evidence suggests that a number of members 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 this speciation?

All offspring will have short-haired fur.

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 cat's fur is controlled by another autosomal gene that occurs in the dominant form, (S), or the recessive form, (s). The table below shows the traits for these allele codes. Gene Trait B black fur b white fur S short-haired fur s long-haired fur The following genotypes were found in a male cat and a female cat. BbSs (male) bbSS (female) Which one of the following choices is true of the phenotype of offspring from these parents?

inserting foreign genes into fertilized goat eggs

Genetic engineering has produced goats whose milk contains proteins that can be used as medicines. This effect was produced by

Bacterial diseases respond to antibiotics; viral diseases do not.

How do human diseases caused by bacteria and diseases caused by viruses react to antibiotics?

Ty, ty

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 this plant?

The allele is on the X chromosome.

If a human baby boy inherits a recessive allele from his mother, in which circumstance would he most likely show the trait coded for by the recessive allele?

biological diversity.

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

The smallmouth bass population will die.

In a pond, the primary producer is a green alga, Spirogyra; the primary consumer is the crustacean, Daphnia; the secondary consumer is a small fish, the bluegill; and the tertiary consumer is a larger fish, the smallmouth bass. What changes can be expected in the pond if the Daphnia are killed with pesticides?

mitochondria

In aerobic respiration, the Krebs cycle (citric acid cycle) takes place in

are heterozygous for the disease.

In carrier pigeons there is a rare 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

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?

RR, Rr, and rr only

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)?

hypothesis

In most stable freshwater environments, populations of Daphnia are almost entirely female and reproduce asexually. However, males are observed in low oxygen environments or when food is scarce. Based on these observations, a researcher suggests that male Daphnia develop in response to unfavorable environmental conditions. This is an example of a

waste removal.

In order for the body to maintain homeostasis, the chemical decomposition of food to produce energy must be followed by

are unable to fight off these pneumonia- causing organisms.

Individuals with HIV sometimes contract a pneumonia infection that is rare in the rest of the population because people with HIV

stimulate the production of antibodies which can be manufactured later in response to infection.

Injecting a person with a killed-bacteria vaccine can protect that individual from a disease because the proteins of the killed bacteria

diluting with water

Maltose can be broken down into glucose molecules by the enzyme maltase. Which of the following would slow the reaction rate?

haploid cells are produced by meiosis.

Mendel hypothesized that reproductive cells have only one factor for each inherited trait. This hypothesis is supported by the observation that

natural processes that produce genetic diversity.

Mutations within a DNA sequence are

lizards

Numbers of Representative Species

a mutation

One human disease is caused by a change in one codon in a gene from GAA to GUA. This disease is the result of

chc

Rabbit coat color Allele-Phenotype C-Rabbit with fully colored coat; cch-Rabbit with light gray coat; ch-Himalayan rabbit: white with dark ear tips, nose, paws, and tail; c-Albino rabbit Order of dominance C-cch-ch-c The chart shows four alleles at the same locus that affect rabbits' coat color. Each allele is dominant to the ones below it. Rabbits with an albino or Himalayan coat are more susceptible to predators. Which of the following genotypes will produce a rabbit that is least likely to survive?

There are few effective predators.

Rabbits introduced into Australia 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 explanation for their increased numbers?

The abiotic characteristics of the habitat changed.

Scientists found that, over a period of 200 years, a mountain pond was transformed into a meadow. During that time, several communities of organisms were replaced by different communities. Which of these best explains why new communities were able to replace older communities?

each half of the original DNA molecule is joined with a new complementary DNA strand.

Semi-conservative replication of DNA refers to the idea that

applying ice to the bite area.

Some snake venoms are harmful because they contain enzymes that destroy blood cells or tissues. The damage caused by such a snakebite could best be slowed by

reflex reactions

Striking the tendon just below the kneecap causes the lower leg to jerk. Moving an object quickly toward the face can cause the eyes to blink shut. These are examples of

a nonspecific defense against infection.

Sweat and skin 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

promote production of antibodies

The Sabin vaccine is a liquid containing weakened polio viruses. Vaccinated individuals become protected against polio because the weakened viruses

genetic manipulation

The bacterium Agrobacterium tumefaciens infects plants, and a portion of its DNA is inserted into the plant's chromosomes. This causes the plant to produce gall cells, which manufacture amino acids that the bacterium uses as food. This process is a natural example of

semi-permeable

The cell membrane of the 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

changes the protein structure

The clear protein of an egg white becomes opaque and firm when cooked because the heat

crossing-over in which alleles are exchanged

The diagram above shows homologous chromosomes during prophase I of meiosis. Which of the following correctly describes the process being illustrated?

It was used to determine the physical structure of DNA.

The diagram below shows Rosalind Frankin's x-ray diffraction image of DNA. How did this evidence affect the work of Watson and Crick?

meiosis

The diagram below shows a cellular process that occurs in organisms. This process is known as

adrenaline secreted by the adrenal glands.

The fight-or-flight response includes greater heart output and a rise in blood pressure. This response is due to

light-dependent

The first stage of photosynthesis in a chloroplast is

increased.

The graph below shows the birth rate and death rate for a population during the 1900s.

chemical receptors

The homeostatic mechanism in humans that regulates blood pH depends on the feedback of information from

two layers of lipids organized with the nonpolar tails forming the interior of the membrane.

The plasma membrane of a cell consists of

coordinate muscles controlling breathing.

The respiratory system depends on the nervous system for signals to

An organism with favorable genetic variations will tend to survive and breed successfully.

Which of these best illustrates natural selection?

The diploid chromosome number represents pairs of chromosomes, one from each parent, so it is always an even number.

The table below lists the typical diploid number of chromosomes of several different organisms. Diploid Chromosome Number Goldfish-94 Potato-48 Human-46 Pea-14 Fruit fly-8 Which of the following is the best explanation for why the chromosome number is an even number in each of these organisms?

An enzyme binds to a specific substrate (reactant) for the reaction catalyzed.

There are many different enzymes located in the cytoplasm of a single cell. How is a specific enzyme able to catalyze a specific reaction?

variation in the strawberry plants

Two students were testing the amount of fertilizer that would best promote the growth of strawberries in a garden. Which of the following could be an unavoidable source of experimental error?

Low temperatures reduce the action of ripening enzymes

What causes tomatoes to ripen much more slowly in a refrigerator than they do if left on a table at room temperature?

infections in uncovered tissues

What is the greatest danger to a patient who has had damage to the skin?

Z, X, Y, W

When the Mount St. Helens volcano erupted, the blast covered much of the surrounding area with ash. Based on the diagram above, which list shows the sequence of secondary succession that followed that eruption?

Golgi apparatus

Which cellular organelle is responsible for packaging the proteins that the cell secretes?

the structure of a DNA molecule

Which information was most important to the development of genetic engineering techniques?

chlorophyll

Which molecule in plant cells first captures the radiant energy from sunlight?

5' AGTCAT 3' 3' TCAGTA 5'

Which of the following base pair sequences could be produced in DNA replication?

It occurs only in cells in the reproductive structures of the organism

Which of the following best describes meiosis?

They can help predict outcomes

Which of the following best describes the use of population models in biology?

signaling muscle tissues to contract

Which of the following is a function of the nervous system?

viruses

Which of the following require a host cell because they are not able to make proteins on their own?

n+n

Which of the following sequences represents chromosome number during fertilization?

The cells produced at the end of meiosis contain half the number of chromosomes as the parent cell

Which of the following statements correctly describes meiosis?

a plant cell

Which of these best completes this concept map?

Differentiated cells contain a complete set of genes.

Which of these is best demonstrated by the experiment above? Epithelial cell from tadpole intestine. Egg from another frog. Nucleus has been destroyed. Nucleus from tadpole cell is implanted in enucleated egg. Egg develops into frog with the same characteristics of original nucleus-donating tadpole.

fungi and bacteria

Which of these organisms are most helpful in preventing Earth from being covered with the bodies of dead organisms?

sharks

Which of these organisms would most likely be found at the top of an energy pyramid?

green algae

Which of these organisms would most likely be found at the bottom of a biomass pyramid?

thyroid

Which of these secretes a hormone that regulates the rate of metabolism of the body?

chromosome number

Which of these would have the least effect on natural selection in a subspecies of giraffes that is geographically isolated from other subspecies of giraffes?

the insertion of a nucleotide into DNA

Which of these would most likely cause a mutation?