Chapter 3

Question 1

Genetics

Answer 1

The scientific study of heredity

Question 2

Heredity

Answer 2

The passing of physical characteristics from parents to offspring

Question 3

Trait

Answer 3

Specific characteristics

Question 4

Fertilization

Answer 4

When a new organism begins to form due to an egg and a sperm joining

Question 5

Purebred

Answer 5

Offspring of many generations that have the same form of a trait

Question 6

Gene

Answer 6

A factor that controls a trait

Question 7

Alleles

Answer 7

Different forms of gene

Question 8

Dominant allele

Answer 8

One whose trait always shows up in the organism when the allele is present

Question 9

Recessive allele

Answer 9

Hidden whenever the dominant allele is present

Question 10

Hybrid

Answer 10

Has two different alleles for a trait

Question 11

Probability

Answer 11

A number that describes how likely it is that an even will occur

Question 12

Punnett Square

Answer 12

A chart that shows all the possible ways that alleles can combine in a genetic cross

Question 13

Phenotype

Answer 13

How a trait looks or expressed

Question 14

Genotype

Answer 14

An organism’s alleles

Question 15

Homozygous

Answer 15

An organism that has two identical alleles for a trait

Question 16

Heterozygous

Answer 16

An organism that has two different alleles for a trait

Question 17

Incomplete dominance

Answer 17

Occurs when one allele in only partially dominant

Question 18

Codominance

Answer 18

Occurs when both alleles for a gene are expressed equally

Question 19

Multiple alleles

Answer 19

Mean that’s three or more possible alleles determine the trait

Question 20

Polygenic inheritance

Answer 20

Occurs when more than one gene affects a trait

Question 21

Meiosis

Answer 21

Is the process by which the number of chromosomes in reduced by half as sex cells form.