Ch10 Foundations Of Genetics Exam Questions

Essentials of The Living World, 6e (Johnson)

Chapter 10 Foundations of Genetics

1) Gregor Mendel's work was different from that of other researchers working on inheritance in his day because he

A) was a religious man.

B) worked with pea plants.

C) knew how to grow plants.

D) counted the numbers and types of offspring.

E) studied both math and science.

2) In Mendel's initial experiments, he crossed two true-breeding pea plants, one with purple flowers (the dominant trait) and the other with white (the recessive trait). Their offspring, the F1 generation, were

A) non-true-breeding with purple flowers.

B) true-breeding with white purple flowers.

C) non-true-breeding with white flowers.

D) true-breeding with white flowers.

E) non-true-breeding with both purple and white flowers.

3) The offspring of the P generation are referred to as the

A) true recessives.

B) testcross.

C) F1 generation.

D) F2 generation.

E) P1 generation.

4) Tall is dominant to dwarf in pea plants. If two dwarf pea plants were crossed, their offspring will be

A) all tall plants.

B) all dwarf plants.

C) half tall and half dwarf plants.

D) plants of an intermediate height.

E) one dwarf and three tall.

5) Free earlobes are dominant over attached earlobes. What is the probability that a woman with attached earlobes (homozygous recessive) will have children with attached earlobes if their father has free earlobes (heterozygous)?

A) 1 in 2

B) 3 in 4

C) 1 in 10

D) None of the children will have attached earlobes.

E) All of the children will have attached earlobes.

6) In Japanese four o'clock flowers, pink-flowered plants are produced when red-flowered plants are crossed with white-flowered plants. This type of inheritance can best be described as

A) simple dominant and recessive traits.

B) codominance.

C) incomplete dominance.

D) sex-linked traits.

E) pleiotropic.

7) If several traits are affected by the same allele, the allele is said to be

A) recessive.

B) dominant.

C) epistatic.

D) pleiotropic.

E) codominant.

8) Yellow pea seeds are dominant over green pea seeds. What is the probability of getting a pea plant with green seed color when crossing two heterozygous pea plants?

A) 1 in 6

B) 1 in 4

C) about half

D) None, all will be yellow.

E) All will be yellow.

9) In the human ABO blood grouping, there are four basic blood types: A, B, AB, and O. The blood proteins A and B are

A) simple dominant and recessive traits.

B) codominant.

C) incompletely dominant.

D) sex-linked traits.

E) pleiotropic.

10) Foxes, cats, and rabbits have enzymes that are heat-sensitive, causing a seasonal variation in coat color due to

A) an environmental effect.

B) multiple alleles.

C) pleiotropy.

D) incomplete dominance.

E) codominance.

11) The diploid number of chromosomes in humans is 46. The haploid number is

A) 138.

B) 92.

C) 46.

D) 23.

E) None of the answer choices are correct.

12) To determine a plant's actual genetic composition, Mendel devised and used a

A) dihybrid cross.

B) testcross.

C) monohybrid cross.

D) true-breeding cross.

E) non-true-breeding cross.

13) Down syndrome in humans is due to ________ of the 21st chromosome.

A) three copies

B) two copies

C) 4 copies

D) one copy

E) None of the answer choices are correct.

14) Humans who have lost one copy of an autosome are called ________ and generally do not survive development.

A) monosomics

B) trisomics

C) eusomics

D) diploids

E) None of the answer choices are correct.

15) Hemophilia is a group of different inherited blood-clotting disorders. Which is true about hemophilia?

A) It causes sterility.

B) It is more common in females than in males.

C) It is more common in males than in females.

D) It is inherited only on the autosomes.

E) It is found on the Y chromosome.

16) Human height shows a continuous variation from very short to very tall. Height is most likely controlled by

A) a single gene.

B) sex-linked genes.

C) the environment.

D) multiple genes.

E) codominant alleles.

17) White flower color is recessive to purple. What is the genotypic ratio when two heterozygous pea plants are crossed?

A) 3 : 1

B) 4 : 0

C) 1 : 2 : 1

D) 1 : 1 : 1

E) All of the plants will be purple.

18) The ability to taste phenylthiocarbamide (PTC) is a dominant trait. If a heterozygous woman has a child with a man who is not a taster, what is the chance their child will be a taster?

A) 100%

B) 75%

C) 50%

D) 25%

E) 0%

19) Nondisjunction of chromosomes resulting in aneuploidy occurs during ________ of meiosis.

A) anaphase I

B) prophase I

C) metaphase II

D) anaphase I or II

E) metaphase I or II

20) Which cross represents a dihybrid cross?

A) RRrr × DdDd

B) RR × Dd

C) RrDd × RRdd

D) RD × Rd

E) Rd × RR

21) Genes are made of

A) ribosomes.

B) cytoplasm.

C) protein.

D) DNA.

E) lipids.

22) Where are genes located in the cell?

A) on chromosomes

B) part of the endoplasmic reticulum

C) part of the Golgi complex

D) free floating in the cytoplasm

E) within the plasma membrane

23) Which statement accurately describes how genotypes determine phenotypes?

A) Proteins determine the sequence of genes.

B) Amino acids are located on chromosomes and determine what genes will be expressed.

C) Associations of proteins form polypeptides, which contain genes.

D) Genes encode a sequence of amino acids for a particular polypeptide or protein.

E) Genes are located on proteins, which encode a sequence of amino acids.

24) The closer two genes are to each other on a chromosome, the more likely they are to segregate independently.

25) The outward expression of an organism's genotype is referred to as its genotype.

26) Mendel referred to traits as "factors" for inheritance. These are now known to be ________.

27) An individual is said to be ________ if it has two copies of the same factor for a given trait.

28) A recessive human genetic disorder that results in low oxygen delivery to tissues is called ________ disease.

29) Mendel's law that states only one allele specifying an alternative trait can be carried in a particular gamete is called the law of ________.

30) When homologous chromosomes or chromatids fail to separate properly in meiosis, this is called ________.

31) When an allele has more than one effect on a phenotype, it is said to be ________.

32) If a white-flowered pea plant (ww) is crossed with a heterozygous purple-flowered plant (Ww), what will their offspring look like?

33) Children look like their parents because they share genes. The tendency for children to acquire traits from their parents is called ________.

34) Mendel used the garden pea plant in his studies because of their ease to work with. Select all of the following garden pea characteristics that made them easy to work with.

A) There are few varieties available.

B) There were previous experiments that made counting his results reliable.

C) They are self-pollinating.

D) They are available in white and purple coloration.

E) The pea plants grow very large and bushy.

35) Recessive traits are always expressed.

36) In Mendel's third hypothesis, he stated alternative forms of a factor lead to alternative traits. The alternative forms of a factor were, and are still, called ________.

37) In biology lab, you are asked to use a dihybrid cross to determine what the seedlings will look like. You are being asked to predict the offspring's

A) genotype.

B) alleles.

C) phenotype.

D) genes.

E) heredity.

38) In biology lab, you and your classmates are recreating Mendel's experiments. After crossing pea plants, you observe a large variation of peas related to their texture and color. You are witnessing Mendel's law of

A) segregation.

B) inheritance.

C) independent assortment.

D) codominance.

E) recessive.

39) A male who has many female characteristics and is sterile may have Klinefelter syndrome. If this is true, his sex chromosomes would be

A) XXX

B) XY

C) XXY

D) XYY

E) XX

40) A karyotype shows an extra copy of an autosome. This individual has a form of ________.

41) Individuals with hemophilia need to be concerned when having surgeries because they are more likely to form excess bloods clots.