1.    Each human body cell contains _____ chromosomes.

A)    46 pairs of

B)    46

C)    23

D)    20 pairs of

2.    A small section of a chromosome that is the basic unit for the transmission of heredity is a _____.

A)    chromosome

B)    gene

C)    genotype

D)    zygote

3.    The name of the full set of genes that provides the instructions for making living organisms is the _____.

A)    phenotype

B)    genotype

C)    genome

D)    allele

4.    Each human has a total of about _____ genes.

A)    10,000

B)    20,000

C)    30,000

D)    40,000

5.    Each gene directs the formation of specific proteins made from a string of _____ amino acids.

A)    10

B)    20

C)    30

D)    40

6.    All living things are composed of cells. The work of cells is done by _____.

A)    proteins

B)    zygotes

C)    genotypes

D)    phenotypes

7.    Each molecule of deoxyribonucleic acid (DNA) is stored on a(n) _____.

A)    chromosome

B)    RNA

C)    gene

D)    zygote

8.    One aspect of both nature and nurture that profoundly affects each person is the _____, which refers to all microbes that live within every part of the body.

A)    genome

B)    allele

C)    microbiome

D)    zygote

9.    A variation that makes a gene different in some way from other genes for the same characteristics is a(n) _____.

A)    chromosome

B)    zygote

C)    genotype

D)    allele

10.    The process of methylation can do all the following to genetic instructions EXCEPT _____ them.

A)    alter

B)    connect

C)    remove

D)    transcribe

11.    Some genes are _____, which means “many forms.”

A)    polymorphic

B)    multimorphic

C)    allelemorphic

D)    transmorphic

12.    Dr. Garcia studies how environmental factors affect gene expression—enhancing, halting, shaping, or altering the expression of genes. Dr. Garcia studies _____.

A)    atypical longevity

B)    sociobiology

C)    human pathogenesis

D)    epigenetics

13.    The single cell formed from the union of two gametes, a sperm and an ovum, is called a “_____.”

A)    chromosome

B)    phenotype

C)    genotype

D)    zygote

14.    Every human begins life as a single cell, which is called a _____.

A)    chromosome

B)    zygote

C)    genotype

D)    genome

15.    Humans have 23 pairs of _____, which contain the instructions to make the proteins needed for life and growth.

A)    chromosomes

B)    alleles

C)    genotypes

D)    zygotes

16.    The instructions for making amino acids are on about 3 billion pairs of chemicals called “_____ pairs.”

A)    couple

B)    foundation

C)    base

D)    copy

17.    An individual's genetic inheritance is called a(n) “_____.”

A)    phenotype

B)    allele

C)    genotype

D)    gamete

18.    In 22 of the 23 pairs of chromosomes, both members of the pair are closely matched. Each of these 44 chromosomes is called a(n) “_____.”

A)    allele

B)    gamete

C)    autosome

D)    blastocyst

19.    The first 22 chromosomes contain hundreds of genes in the same positions and sequence. If the code of the gene from one parent is exactly like the code on the same gene from the other parent, the gene pair is _____.

A)    homozygous

B)    heterozygous

C)    monozygotic

D)    dizygotic

20.    The first 22 chromosomes contain hundreds of genes in the same positions and sequence. If the code of the gene from one parent differs from the code on the same gene from the other parent, the gene pair is _____.

A)    homozygous

B)    heterozygous

C)    monozygotic

D)    dizygotic