Deck 45: Principles of Heredity

Question 1

How many autosomes pairs do humans have?

A) 1
B) 22
C) 11
D) 23

Answer 1

B

Question 2

Incomplete dominance occurs when .

A) only the recessive allele is expressed
B) only the dominant allele is expressed
C) each of the alleles is partially expressed

Answer 2

C

Question 3

Autosomes are pairs of chromosomes that contain genes for determining .

A) characteristics for internal organs
B) characteristics for surface features
C) body characteristics
D) the sex of the individual

Answer 3

C

Question 4

What is true about the sex chromosomes?

A) Possession of the Y chromosome determines maleness.
B) Normal females possess two sex chromosomes that look different, X and Y, and normal males possess two sex chromosomes that look the same, X and X.
C) Normal males possess two sex chromosomes that look the same, X and X.
D) Normal females possess two sex chromosomes that look different, X and Y.

Question 5

ABO blood types are determined by three alleles designated IA, IB, and i. A person with alleles IA and i will have the blood type .

A) B
B) O
C) A
D) AB

Question 6

Genotype is _.

A) the manner in which a particular trait is expressed
B) an individual's actual genetic makeup
C) the diploid number of chromosomes in an individual
D) the expression of sex chromosomes in an individual

Question 7

The genes for color blindness are sex-linked and recessive. What is not true about the expression of color blindness?

A) It is infrequently seen in women.
B) Fathers can transmit sex-linked genes to their daughters.
C) It is frequently seen in women.
D) Fathers cannot transmit sex-linked genes to their sons.

Question 8

Inheritance of ABO blood types is an example of .

A) sex-linked inheritance
B) incomplete dominance
C) codominance

Question 9

If white flowers are crossed with red flowers and the resulting plants have pink flowers, that condition is known as .

A) total dominance
B) sex-linked inheritance
C) total heterozygosity
D) incomplete dominance

Question 10

If the parental genotypes for sickle cell anemia/trait are Ss and ss, what is the probability of offspring having the sickle cell trait? If there is some probability of offspring having sickle cell anemia, what is that probability?

A) trait 50%; anemia 50%
B) trait 25%; anemia 75%
C) trait 75%; anemia 25%

Question 11

If the genotype of an individual contains alleles for a particular trait that differ in their expression, the individual is said to be for that trait.

A) heterozygous
B) homozygous
C) recessive

Question 12

A complement of an individual's chromosomes displayed as homologous pairs is called the .

A) genotype
B) karyotype
C) phenotype

Question 13

If a person is homozygous for a particular trait, the alleles for that trait .

A) differ in their expression
B) are unrelated to the expression of that trait
C) have the same expression

Question 14

Predict the phenotype of a particular individual if the genotype of both parents is TT (T determines tallness, it is dominant; t determines dwarfism, it is recessive).

A) Tt
B) the person is short
C) the person is tall
D) TT

Question 15

Genes present only on the X chromosome are called _.

A) sex-linked genes
B) male genes
C) female genes
D) These genes do not have a special name.

Question 16

What is the probability of a male having color blindness if his X chromosome carries the c allele? (He is Xc. XC determines normal color vision, it is dominant. Xc determines color blindness.)

A) 100%
B) 50%
C) 0%
D) 25%

Question 17

If an individual has alleles for a particular trait that differ in their expression, and one of the alleles always exerts its effect, the individual is said to express the _ gene.

A) combined
B) recessive
C) dominant
D) crossed

Question 18

A pair of chromosomes, one from the egg and one from the sperm, that carry complete (or nearly complete) genetic instructions for the same traits are called _.

A) a homologous pair
B) biparental genes
C) the paternal genotype
D) dominant genes

Question 19

Alleles are _.

A) chromosomes that have been duplicated prior to mitosis
B) recessive genes
C) genes coding for the same trait on a pair of homologous chromosomes
D) dominant genes

Question 20

The inheritance of sickle cell anemia involves incomplete dominance. (S determines normal hemoglobin, it is dominant; s is the sickle cell gene). A homozygous recessive person has sickle cell anemia. A heterozygous person has the sickle cell trait. If parental genotypes are SS and ss, what is the probability of offspring having the sickle cell trait?

A) 50%; half are Ss
B) 25%; one quarter are Ss
C) 100%; all are Ss

Question 21

The probability of a certain event occurring is defined as: P = number of specific events/total number of events. If an event happens one out of every two times its probability is _.

A) 100%
B) 25%
C) 50%
D) 10%

Question 22

You observe that your friend has dimples. Dimples result from the presence of the dominant gene D; absence of dimples is a homozygous recessive condition (dd). What genotype or genotypes might your friend have?

A) DD only
B) DD or Dd
C) dd only
D) Dd only

Question 23

You have performed electrophoresis on a sample of normal hemoglobin (HbA), sickle-cell hemoglobin (HbS), a mixture containing HbA + HbS, and a sample of hemoglobin from a patient. The patient sample shows 2 bands, one at the same distance as the HbA band and one at the same distance as the HbS band. What is true about your patient?

A) The patient has sickle-cell anemia.
B) The patient has sickle-cell trait.
C) The patient has normal hemoglobin.
D) The answer cannot be determined from the data.

Question 24

You notice that both of your parents have a widow's peak that is determined by the dominant allele W. You however, have a straight hairline, which is a homozygous recessive condition (ww). What are the possible genotypes of your parents?

A) Ww and Ww
B) WW and Ww
C) ww and ww
D) WW and WW

Question 25

If the probability of an event occurring is 50%, what is the probability of that event occurring 5 times in a row?

A) 1/2
B) 1/20
C) 1/8
D) 1/32