Chapter 4: Genes, Gene-environment Interaction, And Epigenetics

Question 1

The basic unit of inheritance

Answer 1

Genes

Question 2

Name the four nitrogenous bases

Answer 2

Adenine (A)
Cytosine (C)
Guanine (G)
Thymine (T)

Question 3

Each DNA subunit—consisting of one deoxyribose molecule, one phosphate group, and one base

Answer 3

Nucleotide

Question 4

This consists of the breaking of the weak hydrogen bonds between the bases, leaving a single stand with each base unpaired

Answer 4

DNA replication

Question 5

This enzyme travels along the subtle DNA strand, adding the correct nucleotides to the free end of the new strand

Answer 5

DNA polymerase

Question 6

Any inherited alteration of genetic material

Answer 6

Mutation

Question 7

A large number of agents that can increase the frequency of mutations

Answer 7

Mutagens

Question 8

The transport of the DNA code from nucleus to cytoplasm and the subsequent protein formation involves these two processes

Answer 8

Transcription

Translation

Question 9

The process by which RNA is synthesized from a DNA template

Answer 9

Transcription

Question 10

The result of transcription is the formation of:

Answer 10

messenger RNA (mRNA)

Question 11

How does RNA differ from DNA?

Answer 11

RNA uses uracil (U) as a base amino acid rather than thiamine (T)

Question 12

Transcription continues until a DNA sequence called _______ ________ is reached

Answer 12

Termination sequence

Question 13

The process by which RNA directs the synthesis of a polypeptide

Answer 13

Translation

Question 14

Translation utilizes this which is a clover shaped strand it about 80 nucleotides

Answer 14

Transfer RNA (tRNA)

Question 15

Human cells can be categorized into two types:

Answer 15

Germline (sperm and egg, or gametes)

Somatic cells (including all other cells)

Question 16

Gametes are ________ cells, so only 1 member of each chromosome pair

Answer 16

Haploid

Question 17

The process by which these haploid cells are formed from diploid cells is called

Answer 17

Meiosis

Question 18

The most well known form of aneuploidy is

Answer 18

Trisomy 21

Question 19

Broken chromosomes and loss of DNA cause

Answer 19

Deletions

Question 20

The occurrence of two breaks in a chromosome, followed by the reinsertion its missing fragment at its original site, but in inverted order

Answer 20

Inversion

Question 21

The interchange of genetic material between nonhomologous chromosomes

Answer 21

Translocation

Question 22

Each gene occupies a position along a chromosome known as a

Answer 22

Locus

Question 23

Genes at a particular locus can take different forms, known as

Answer 23

Alleles

Question 24

When two alleles are identical, the individual is __________. When the alleles are different, they are _____________.

Answer 24

Homozygous

Heterozygous

Question 25

The composition of genes at a given locus is known as

Answer 25

Genotype

Question 26

The outward appearance of an individual

Answer 26

Phenotype

Question 27

The ___________ of a trait is the percentage of individuals with a specific genotype who also exhibit the expected phenotype

Answer 27

Penetrance

Question 28

The most common lethal recessive disease in white children

Answer 28

CF

Question 29

___________ refers to the mating of two related individuals and their offspring are said to be _________

Answer 29

Consanguinity Inbred

Question 30

A trait that occurs much more often in one sex than the other

Answer 30

Sex-Influenced trait

Question 31

Different version of a paired gene

Answer 31

Allele

Question 32

Substance that alters genetic material

Answer 32

Mutagen

Question 33

Chromosome that is not a sex chromosome

Answer 33

Autosome

Question 34

Segment of DNA that is the basic unit of inheritance

Answer 34

Gene

Question 35

Sequence it three nitrogenous bases that specifies a particular amino acid

Answer 35

Codon

Question 36

No coding segment spliced out of mRNA

Answer 36

Intron

Question 37

Alteration of DNA capable of being passed off to offspring

Answer 37

Mutation

Question 38

Segment of mRNA that codes for proteins

Answer 38

Exon

Question 39

Strand of condensed chromatin visible right before cell division

Answer 39

Chromosome

Question 40

A display of chromosomes ordered according to length and centeomere location is called

Answer 40

Karyotyoe

Question 41

A somatic cell has how many pairs of chromosomes

Answer 41

23

Question 42

A _________ mutation of DNA involves addition or deletion of a number of base pairs that is not a multiple of three and thus alters all the codons downstream from the site of insertion or deletion

Answer 42

Frameshift

Question 43

A ______ gene will only be displayed if two copies are present

Answer 43

Recessive

Question 44

Person who has Down syndrome has a high risk of developing _________ disease because of involvement with chromosome 21

Answer 44

Alzheimer’s

Question 45

Person with the 47,XXY karyotyoe have ______ syndrome

Answer 45

Klinefelters

Question 46

X-linked recessive diseases are seen much more often in ——- rather than _______

Answer 46

Males more than females

Question 47

An error during mitosis or meiosis where homologous chromosomes fail to separate normally

Answer 47

Nondisjunction