AP Biology Unit 4 Study Guide

To protect U.S. soldiers serving overseas, each soldier receives vaccinations against several diseases, including smallpox, before deployment. Following intelligence about an imminent smallpox threat, the Army wants to ensure that soldiers stationed in Iraq are fully protected from exposure to the disease, so all the soldiers in the threat zone are given a second vaccination against smallpox. The first vaccination provides immunity because

Antigenic determinants in the vaccine activate B cells, which produce antibodies to counter the antigen in the vaccine.

Which of the following compounds is produced and secreted by mast cells during an allergic reaction? a. histamine b. interferon c. allergens d. perforin

a.

Which of the following statements is false? a. Incomplete dominance supports the blending hypothesis.This is the correct answer. b. Heterozygotes for hypercholesterolemia have blood cholesterols about twice normal. c. The four blood types result from various combinations of the three different ABO alleles. d. ABO blood groups can provide evidence of paternity. e. The impact of a single gene on more than one character is called pleiotrophy.

a.

A molecule that can elicit an adaptive immune response is called

an antigen

A substance that can ellicit an immune response is called

an antigen

Complement can be activated by

antigen-antibody complexes

A person with AB blood illustrates the principles of a. incomplete dominance b. codominance c. pleiotrophy d. polygenic inheritance e. blending inheritance

b.

All the offspring of a cross between a black-eyed mendelian and an orange-eyed mendelian have black eyes. What is the expected phenotypic ratio of a cross between two orange-eyed mendelians? a. 3 black-eyed: 1 orange-eyed b. 0 black-eyed: 1 orange-eyed c. 1 black-eyed: 1 orange-eyed d. 1 black-eyed: 0 orange-eyed e. 1 black-eyed: 1 orange-eyed

b.

Any gene located on a sex chromosome a. is called a recessive gene. b. is called a sex-linked gene. c. is called a dominant allele. d. will exhibit pleiotropy. e. will exhibit codominance.

b.

Sickle-cell disease is an example of

codominance and pleiotropy

The human lymphatic system consists of all of the following structures except the a. thymus b. tonsils c. spleen d. pancreas e. appendix

d.

If A is dominant to a and B is dominant to b, what is the expected phenotypic ratio of the cross: AaBb x AaBb? a. 16:0:0:0 b. 8:4:2:2 c. 4:4:4:4 d. 1:1:1:1 e. 9:3:3:1

e.

The alleles of a gene are found at ____________ chromosomes. a. the same locus on homologous mitochondrial b. the same locus on heterologous c. different loci on homologous d. different loci on heterologous e. the same locus on homologous

e.

When you cut yourself, the damaged cells immediately release chemical alarm signals, such as

histamine

Imagine that the beak color in a finch species is controlled by a single gene. You mate a finch homozygous for orange (pigmented) beak with a finch homozygous for ivory (unpigmented) beak and get numerous offspring, all of which have a pale, ivory-colored beak. This pattern of color expression is most likely to be an example of

incomplete dominance

All the offspring of a cross between a red-flowered plant and a white-flowered plant have pink flowers. This means that the allele for red flowers is __________ to the allele for white flowers.

incompletely dominant

What helps activate our nonspecific(innate) defense system?

inflammation

Antibodies are

proteins

What type of immune response is always disadvantageous to a person?

Autoimmune

________ can destroy infected cells.

Cytotoxic T cells

Which of the following cell types is responsible for cell-mediated immunity?

T cells

A carrier of a genetic disorder who does not show symptoms is most likely to be ___________ to transmit it to offspring. a. heterozygous for the trait and able b. heterozygous for the trait and unable c. homozygous for the trait and able d. heterozygous for the trait and unable e. heterozygous for the trait and unlikely

a.

A testcross is a. a mating between an individual of unknown genotype and an individual homozygous recessive for the trait of interest. b. a mating between an individual of unknown genotype and an individual heterozygous for the trait of interest. c. a mating between an individual of unknown genotype and an individual homozygous for the trait of interest. d. a mating between two individuals heterozygous for the trait of interest. e. a mating between two individuals of unknown genotype.

a.

For most sexually reproducing organisms, Mendel's laws a. cannot strictly account for most patterns of inheritance. b. explain the reasons why certain genes are dominant. c. help us understand the global geographic patterns of genetic disease. d. indicate if a particular genotype will cause a certain phenotype. e. clarify the phenomenon of incomplete dominance.

a.

Which of the following shows the steps of a viral infection in the proper order? a. virus locates host cell → penetrates cell membrane → enters nucleus → alters host cell DNA → host cell produces copies of virus b. virus locates host cell → forms hydrogen bonds → changes DNA to RNA→ host cell produces copies of virus c. virus locates host cell → alters host cell DNA → host cell produces copies of virus → copies enter host cell nucleus → nucleus leaves cell d. virus locates host cell → enters nucleus → alters host cell DNA → destroys cell membrane

a.

Which of the following statements about the humoral immune response is true? a. The humoral immune response defends primarily against bacteria and viruses present in body fluids. b. The humoral immune response defends against bacteria and viruses by activating T cells. c. The humoral immune response plays a major role in protecting the body from cancerous cells. d. The humoral immune response is the result of macrophages producing antibodies.

a.

Assuming that the probability of having a female child is 50% and the probability of having a male child is also 50%, what is the probability that a couple's first-born child will be female and that their second-born child will be male? a. 20% b. 25% c. 50% d. 75% e. 100%

b.

Crossing-over _________ genes into assortments of _________ not found in the parents. a. recombines unlinked .... genes b. recombines linked ..... alleles c. combines unlinked ..... alleles d. combines linked ..... genes e. recombines unlinked ..... chromosomes

b.

Passive immunity depends upon a. a person's own immune system producing antibodies b. antibodies made by another organism c. antibody-producing cells from another organism d. antigens from a person's own body e. isoantibodies

b.

Research since Mendel's time has established that the law of segregation of genes during gamete formation a. applies to all life forms. b. applies to all sexually reproducing organisms.. c. applies to all asexually reproducing organisms. d. applies only to unicellular organisms. e. is invalid.

b.

Sex-linked conditions are more common in men than in women because a. men acquire two copies of the defective gene during fertilization. b. men need to inherit only one copy of the recessive allele for the condition to be fully expressed. c. women simply do not develop the disease regardless of their genetic composition. d. the genes associated with the sex-linked conditions are linked to the Y chromosome, which determines maleness.

b.

The major result of the inflammatory response is to a. initiate the production of antibodies b. remove contaminating microorganisms and initiate repair of damaged tissues c. initiate cell-mediated immune responses d. initiate humoral-mediated immune responses e. initiate the production of killer cells

b.

The transfer of antibodies in breast milk to an infant is an example of ___________________ immunity. a. nonspecific b. passive c. humoral d. active e. cell-mediated

b.

To protect U.S. soldiers serving overseas, each soldier receives vaccinations against several diseases, including smallpox, before deployment. Following intelligence about an imminent smallpox threat, the Army wants to ensure that soldiers stationed in Iraq are fully protected from exposure to the disease, so all the soldiers in the threat zone are given a second vaccination against smallpox.The first vaccination provides immunity because a. a localized inflammatory response is initiated. b. antigens in the vaccine activate B cells, which form plasma cells as well as memory cells. c. the vaccine contains manufactured antibodies against smallpox. d. the vaccine contains antibiotics and other drugs that kill the smallpox virus.

b.

Which of the following distinguishes the secondary immune response from the primary immune response? a. The primary response is specific; the secondary one is not. b. The secondary response is faster and stronger. c. The secondary response allows additional antigens to be recognized faster. d. The primary response involves B cells; the secondary one involves T cells.

b.

Which of the following distinguishes the secondary immune response from the primary immune response? a. The primary response is specific; the secondary one is not. b. The secondary response produces higher levels of antibodies. c. The primary response involves B cells, the secondary one involves T cells. Selected:d. The secondary response allows additional antigens to be recognized faster. e. The secondary response only functions with the help of complement.

b.

Which of the following is an example of incomplete dominance in humans? a. sickle-cell disease b. hypercholesterolemia c. skin color d. ABO blood groups e. phenylketonuria

b.

Which of the following statements about humoral immunity is true? a. Humoral immunity primarily defends against bacteria and viruses by activating T cells Selected:b. Humoral immunity can be passively transferred by injecting plasma from an immune individual into a nonimmune individual. c. Humoral immunity plays a major role in protecting the body from cancerous cells d. Humoral immunity is the result of macrophages producing antibodies e. HUmoral immunity does not require chemical signals, such as growth factors.

b.

A monohybrid cross is a. the second generation of a self-fertilized plant. b. a breeding experiment in which the parental varieties have only one trait in common. c. a breeding experiment in which the parental varieties differ in only one character. d. a triploid plant that results from breeding two very different plants. e. a breeding experiment in which the parental varieties have only one prominent trait.

c.

Dr. Smith's parents have normal hearing. However, Dr. Smith has an inherited form of deafness. Deafness is a recessive trait that is associated with the abnormal allele d. The normal allele at this locus, associated with normal hearing is D. Dr. Smth's parents could have which of the following genotypes? a. DD and dd b. dd and dd c. Dd and Dd d. DD and DD e. Dd and DD

c.

Female inheritance patterns cannot be analyzed by simply studying the X chromosome because a. the X chromosome is too fragile for long-term analysis. b. the X chromosome is too susceptible to mutations. c. the X chromosome is obtained from both father and mother. d. the X chromosome is too difficult to isolate from the other chromosomes. e. the X chromosome is physically too large to analyze accurately.

c.

Recessive X-linked traits are more likely to be expressed in a male fruit fly than a female fruit fly because a. males are haploid. b. the male's SRY gene doubles the chances that sex-linked genes are expressed. c. the male's phenotype results entirely from his single X-linked gene. d. the male chromosome is more fragile than the female chromosome. e. The male chromosome is more susceptible to mutations.

c.

The body's innate defenses against infection include a. several nonspecific antibodies b. several nonspecific amino acid toxins c. barriers such as dead skin cells and mucus d. increased production of certain hormones nand changes in microcirculation e. memory cells

c.

Which of the following is an immediate effect of histamine release? a. increase in blood pressure b. conversion of histamine to histidine c. dilation of local blood vessels d. blocking of a response to ragweed pollen

c.

Which of the following statements best explains why dominant alleles that cause lethal disorders are less common than recessive alleles that cause lethal disorders. a. Lethal disorders caused by dominant alleles are usually more severe than lethal disorders caused by recessive alleles. b. Unlike lethal disorders caused by recessive alleles, lethal disorders caused by dominant alleles usually cause the death of the embryo. c. Most individuals carrying a lethal dominant allele have the disorder and die before they reproduce, whereas individuals carrying a lethal recessive allele are more likely to be healthy and reproduce. d. The presence of a lethal dominant allele causes sterility. e. Many lethal recessive alleles cause enhanced disease resistance when they are present in the heterozygous state, and carriers of these alleles have more children, on average than other people.

c.

A color-blind woman marries a man who is not color-blind. All of their sons, but none of their daughters, are color-blind. Which of the following statements correctly explains these results? a. The gene for color vision is incompletely dominant to the gene for sex determination. b. The gene for color vision is completely dominant to the gene for sex determination. c. The gene for color vision is codominant with the gene for sex determination. d. The gene for color vision is linked to the X chromosome. e. The gene for color vision is linked to the Y chromosome.

d.

Amniocentesis and chorionic villus sampling allow for ________ and _________ of the fetus so that it can be tested for abnormalities. a. imaging ...... biochemical testing b. imaging ...... karyotyping c. sexing ...... imaging d. karyotyping ...... biochemical testing e. direct observation ...... biochemical testing

d.

Genes located close together on the same chromosomes are referred to as __________ genes and generally ___________. a. associated ...... sort independently during meiosis b. linked ...... sort independently during meiosis c. homologous ...... are inherited together d. linked ...... do not sort independently during meiosis e. codependent ...... do not sort independently during meiosis

d.

Imagine that we mate two black Labrador dogs with normal vision and find that three of the puppies are like the parents, but one puppy is chocolate with normal vision and another is black with PRA (progressive retinal atrophy, a serious disease of vision). We can conclude that a. both of the parents are homozygous for both traits. b. one of the parents is homozygous for both traits. c. the same alleles that control coat color can also cause PRA. d. the alleles for color and vision segregate independently during gamete formation. e. the alleles for color and vision segregate dependently during gamete formation.

d.

Mendel's law of independent assortment states that a. chromosomes sort independently of each other during mitosis and meiosis. b. genes sort independently of each other in animals but not in plants. c. independent sorting of genes produces polyploid plants under some circumstances. d. each pair of alleles segregates independently of the other pairs of alleles during gamete formation. e. genes are sorted concurrently during gamete formation.

d.

The adaptive immune system is capable of mounting specific responses to particular microorganisms because a. stem cells determine which type of B and T cells to make. b. lymphocytes are able to change their antigen specificity as required to fight infection. c. stem cells make different antigen receptors depending on the invading microorganism. d. the body contains an enormous diversity of lymphocytes, each with the ability to respond to a different antigen.

d.

To protect U.S. soldiers serving overseas, each soldier receives vaccinations against several diseases, including smallpox, before deployment. Following intelligence about an imminent smallpox threat, the Army wants to ensure that soldiers stationed in Iraq are fully protected from exposure to the disease, so all the soldiers in the threat zone are given a second vaccination against smallpox.The second vaccination is beneficial because a. it requires two injections to stimulate antibody formation. b. it contains plasma cells that survive longer than 4-5 days. c. it keeps previously produced plasma cells circulating in the bloodstream. d. it stimulates production of a higher concentration of antibodies in the bloodstream.

d.

Which of the following statements regarding cross-breeding and hybridization is false? a. The offspring of two different varieties are called hybrids. b. Hybridization is also called a cross. c. The parental plants of a cross are the P generation. d. The hybrid offspring of a cross are the P1 generation e. The hybrid offspring of an F1 cross are the F2 generation.

d.

Which of the following statements regarding genotypes and phenotypes is false? a. The genetic makeup of an organism constitutes its genotypes. b. An organism with two different alleles for a single trait is said to be heterozygous for that trait. c. Alleles are alternative forms of a gene. d. An allele that is fully expressed is referred to as recessive. e. The expressed physical traits of an organism are called its phenotype.

d.

You conduct a dihybrid cross and then testcross the generation. A _________ ratio would make you suspect that the genes are linked. a. 3:1 b. 1:2:1 c. 1:1:1:1 d. 7:7:1:1 e. 9:3:3:1

d.

All the offspring of a cross between a black-eyed mendelian and an orange-eyed mendelian have black eyes. This means that the allele for black eyes is ___________ the allele for orange eyes.

dominant to

The individual features of all organisms are the result of a. genetics. b. genetics and cytoplasmic determinants. c. the environment. d. the environment and individual needs. e. genetics and the environment.

e.

The two main functions of the lymphatic system are a. coagulating blood and fighting infections b. producing hormones that regulate the immune system and coagulating blood c. producing hormones that regulate the immune system and fighting infections d. returning tissue fluid to the circulatory system and coagulating blood e. returning tissue fluid to the circulatory system and fighting infections

e.

Which of the following kinds of data could be used to map the relative position of three genes on a chromosome? a. the frequencies with which the genes exhibit incomplete dominance over each other b. the frequencies of mutations in the genes c. the frequencies with which the genes are inherited from the mother and from the father d. the frequencies with which the genes are heterozygous e. the frequencies with which the corresponding traits occur together in offspring

e.

Which of the following statements about antibodies is false? a. Antibody molecules are constructed from four polypeptide chains b. Antibodies recognize and bind to particular antigens c. Antibodies assist in eliminating particular antigenic particles d. The polypeptide chains of an antibody molecule have both a V region and a C region e. The antibodies of mammals can be divided into two major classes

e.

Which of the following terms refers to a situation where a single phenotypic character is determined by the additive effects of two or more genes?

polygenic inheritance

Most of a cell's enzymes are

proteins

Most genetic disorders of humans are caused by

recessive alleles