Genetics Test 1

A mutation in a gene that results in the increased expression of a gene best defines what type of mutation?

gain of function

Which of the following elements is responsible for determining male sex in humans?

SRY

What percentage of children will have the AB blood type if one parent is type AB and the other is type O?

0%

A couple each with blood type AB and normal pigmentation have a child with AB blood type and albinism. What is the probability that their next child will have the same phenotype as the first child?

1/8

Tightly curled or wooly hair is caused by a dominant gene in humans. If a homozygous curly-haired person marries a person with straight hair, what percentage of their offspring would be expected to have curly hair?

100%

Polydactyly is expressed when an individual has extra fingers and/or toes and is transmitted via an autosomal dominant allele. Assume that a man with six fingers on each hand and six toes on each foot marries a woman with polydactyly. The couple has a son with normal hands and feet, but the couple's second child has extra digits. What is the probability that their next child will have polydactyly?

3/4

Klinefelter's syndrome in humans, which leads to underdeveloped testes and sterility, is caused by which chromosomal condition?

47, XXY

A recessive allele in dogs causes white spots. If two solid-colored dogs are mated and produce a spotted offspring, what is the percentage chance their next two puppies would be solid-colored?

9/16 = 56.25%

The diploid chromosome number of an organism is usually represented as 2n. Fruit flies have a diploid chromosome number of 8. What would be the expected tetraploid chromosome number in a human?

92

If an F2 generation from a F1 self-cross always yields offspring in a 3:1 phenotypic ratio, which of the following F1 crosses could have occurred?

Aa x Aa

Living organisms with no nuclei are categorized into two major groups, called domains. What groups of the two is defined by the ability to survive in extreme environments?

Archaea

Imagine you discover an unknown species of reptile that has a male to female ratio that is very low in cool climates. As seasonal temperatures warm you notice that the male to female ratio increases. What mode of sex determination appears to be involved?

Class 1 temperature dependance

In the 1600s, William Harvey studied reproduction and development. What is the term given to the theory which states that an organism develops from the fertilized egg by a succession of developmental events that lead to an adult? - epistasis -epigenetics -epilogy -epigenesis

Epigenesis

If a reptile had a null mutation in the aromatase gene what would be the predicted outcome?

Males even in female producing temperatures

In many species, there are eight representatives of each chromosome. In such species, the characteristic number of chromosomes is called the __ number. it is usually symbolized as ___.

Octoploid; 8n

Which of the following is not part of the Y chromosome in humans?

Xic

Which of the following is an example of natural selection? -a bird is effectively able to feed itself by cracking seeds with its wide beak -an opossum can eat infinite amounts of seeds -depending on what a tiger eats, it will gain less or more weight -turtles can effectively be killed by predators in the Galapagos

a bird is effectively able to feed itself by cracking seeds with its wide beak

A cross between two individuals with different phenotypes that resulted in approximately 50% of each type of offspring would indicate the cross was ________. -true breeding dominant to recessive -a heterozygous crossed to another heterozygous -a heterozygous crossed to a homozygous recessive -a homozygous dominant crossed to a homozygous recessive

a heterozygous crossed to a homozygous recessive

In humans, the genetic basis for determining the sex "male" is accomplished by the presence of ________. -a portion of the Y chromosome -one X chromosome -a balance between the number of X chromosomes and the number of haploid sets of autosomes -high levels of estrogen

a portion of the Y chromosome

What is the term given to the theory which put forth the idea that living organisms could arise by incubating nonliving compounds? -a spontaneous selection -a spontaneous generation -a spontaneous creation -a spontaneous genesis

a spontaneous generation

Assuming a typical monohybrid cross in which one allele is completely dominant to the other, what outcome is expected if a homozygous dominant and a homozygous recessive parent are crossed? -half homozygous dominant, half heterozygous -all heterozygous -half homozygous dominant, half homozygous recessive -all homozygous recessive

all heterozygous

Cohesion holds the chromatid arms together prior to ___

anaphase of mitosis

Which protein is responsible for converting androgens into estrogens?

aromatase

Which of the following is not an example of hereditary?

blue-eyes siamese cats are mean

Gain-of-function mutations are associated with being ________. -dominant -recessive -neutral -wild type

dominant

A condition in which one gene pair masks the expression of a nonallelic gene pair is called ________.

epistasis

With incomplete dominance, a likely _______________ratio resulting from a monohybrid cross would be ________. -genotypic, but not phenotypic: 1:2:1 -genotypic ratio; 1:2:2:4 -genotypic and phenotypic ratio; 1:2:1 -phenotypic, but not genotypic; 1:2:1

genotypic and phenotypic ratio; 1:2:1

Mendel utilized the garden pea, Pisum sativum for his studies based on features that include all but ________. -easy to grow -being able to hybridize artificially -reaches maturity in a single season -has visible features with a wide spectrum of intermediates

has visible features with a wide spectrum of intermediates

A fruit fly with a chromosome formulation of X:2A would be which of the following?

male

Which of the following terms defines a chromosome in which the centromere is located as close as possible to the middle of it?

metacentric

The presence of more than two alternative forms of a given gene would be called ________. -multiple alleles -alternation of generations -codominance -hemizygosity

multiple alleles

Which is not a component of RNA?

nucleosome

For an individual with the XXY chromosomal composition, the expected number of Barr bodies in interphase cells is ________.

one

The observable genetic constitution of an organism is referred to as a __

phenotype

The AB blood group is a codominant trait as a result of which of the following? -presence of both A and B cell surface glycoproteins on the same blood cell -presence of both A and B cell surface glycolipids on the same blood cell -presence of A or B cell surface glycoproteins on some blood cells -presence of A or B cell surface glycolipids on some blood cells

presence of both A and B cell surface glycoproteins on the same blood cell

Which of the following represents the correct sequence of events in mitosis?

prophase-prometaphase-metaphase-anaphase-telophase

a branch of biology associated with the analysis of proteins produced by genes is called

proteomics

The process that leads to the development of haploid gametes is best described as ________. -segregation -disjunction -non-disjunction -replication

segregation

Which of the following is not a characteristic of the ABO gene locus? -six possible phenotypes -multiple alleles -codominance -dominant and recessive alleles

six possible phenotypes

Organized by the centrioles, what structures are important in the movement of chromosomes during cell division?

spindle fibers

What significant genetic function occurs in the S phase of the cell cycle?

synthesis of deoxyribonucleic acid

through his experiments with the pea plants, Gregor Mendel established...

that traits are passed from parents to offspring in predictable ways

During interphase of the cell cycle, __

the cell grows

which of the following is not a true statement about mitochondria?

the mitochondrial genome is found in animals but not plants

Mendel crossed two pea plants with round seeds. most, but not all of the offspring were round. Which of the following is true? -round is recessive -the parental round peas were heterozygous -the plants he used were true breeding -wrinkled is co-dominant

the parental round peas were heterozygous

If a population of humans carries an X-linked lethal recessive allele that causes spontaneous abortions in the first trimester, how would you expect this to affect the sex ratio of that population?

the ratio of females to males would increase

The event referred to a disjunction refers to __

the separation of homologous chromosomes only

Alfred Wallace, along with Charles Darwin, formulated __. -the hypothesis of spontaneous generations -the theory of survival -the theory of natural selection -the hypothesis of evolution

the theory of natural selection

The investigative approach of genetics attributed to Gregor Mendel is ________.

transmission genetics

If the wrinkled-wing mutation in Drosophila is dominant and designated Wr, a fruit fly with the genotype Wr/Wr+ would exhibit what phenotype?

wrinkled wings