Chapter 2

Question 1

Genes

Answer 1

Specific sequence of nucleotides and are recipes for making proteins

Question 2

Normal human cells contain _____ chromosomes

Answer 2

46

Question 3

Normal human cells contain _____ pairs of chromosomes

Answer 3

23

Question 4

Mitosis

Answer 4

The cell’s nucleus making an exact copy of all the chromosomes and splitting into two new cells

Question 5

Meiosis

Answer 5

The gamete’s chromosomes duplicate, and then divide twice resulting in four cells containing only half the genetic material of the original gamete

Question 6

Genotype

Answer 6

Refers to the sum total of all the genes a person inherits

Question 7

Phenotype

Answer 7

Refers to the features that are actually expressed

Question 8

Homozygous

Answer 8

Receive either the same version of a gene from our mother and father

Question 9

Heterozygous

Answer 9

If we receive a different version of the gene from each parent

Question 10

Dominant Gene

Answer 10

Genes that express themselves in the phenotype
even when paired with a different version of the gene

Question 11

Recessive Gene

Answer 11

Genes that express themselves only when paired with a similar version gene

Question 12

Alleles

Answer 12

Different versions of a gene

Question 13

Polygenic Genes

Answer 13

The result of several genes

Question 14

Incomplete Dominance

Answer 14

The dominant gene does not completely suppress the recessive gene

Question 15

Carriers

Answer 15

Those who have inherited only one recessive-gene

Question 16

Monozygotic/Identical Twins

Answer 16

Identical twins occur when a fertilized egg splits apart in the first two weeks of development

Question 17

Dizygotic/Fraternal Twins

Answer 17

Two eggs or ova are released and fertilized by two separate sperm

Question 18

Sex-linked Genetic Disorders

Answer 18

The defective gene is found on the X-chromosome

Question 19

Who is at greater risk for sex-linked genetic disorders: men or women?

Answer 19

Men

Question 20

Recessive/Homozygous Disorders

Answer 20

• The individual inherits a gene change from both
  parents
• If the gene is inherited from just one parent, the person is a carrier and does not have the condition

Question 21

Autosomal Dominant (Heterozygous) Disorders

Answer 21

In order to have the disorder, the individual only needs to inherit the gene change from one parent

Question 22

Chromosomal Abnormality

Answer 22

Occurs when a child inherits too many or two few chromosomes

Question 23

Trisomy 21/Down Syndrome

Answer 23

Occurs when there are three rather than two 21st chromosomes

Question 24

What is the most common cause of chromosomal abnormalities?

Answer 24

The age of the mother

Question 25

Sex-linked Chromosomal Abnormality

Answer 25

When the abnormality is on 23rd pair

Question 26

Autosomal Chromosome Disorders

Answer 26

The individual inherits too many or two few
chromosomes

Question 27

Genetic Counseling

Answer 27

A service that assists individuals identify, test for, and explain potential genetic conditions that could adversely affect themselves or their offspring

Question 28

Behavioral Genetics

Answer 28

The scientific study of the interplay between the genetic and environmental contributions to behavior

Question 29

Genotype-Environment Correlation

Answer 29

Refer to the processes by which genetic factors contribute to variations in the environment

Question 30

Passive Genotype-Environment Correlation

Answer 30

Occurs when children passively inherit the genes and the environments their family provides

Question 31

Evocative Genotype-Environment Correlation

Answer 31

Refers to how the social environment reacts to
individuals based on their inherited characteristics

Question 32

Active Genotype-Environment Correlation

Answer 32

Occurs when individuals seek out environments that support their genetic tendencies