Chapter 3

Question 1

Heredity

Answer 1

The passing of physical characteristics from parents to offspring.

Question 2

Trait

Answer 2

Each specific characteristic, such as stem height or seed color.

Question 3

Genetics

Answer 3

The scientific study of heredity.

Question 4

Fertilization

Answer 4

A new organism begins to form when egg and sperm join in the process.

Question 5

Purebred

Answer 5

Organism offspring of many generations that have the same form of a trait.

Question 6

Gene

Answer 6

The factors that control a trait.

Question 7

Alleles

Answer 7

The different forms of a 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

Organism has two different alleles for a trait.

Question 11

Probability

Answer 11

A number that describes how likely it is that an event will occur.

Question 12

Punnett square

Answer 12

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

Question 13

Phenotype and genotype

Answer 13

Two terms that genetics use.

Question 14

Homozygous

Answer 14

An organism that has two identical alleles for a trait.

Question 15

Hererozygous

Answer 15

An organism that has two different alleles for that trait.

Question 16

Meiosis

Answer 16

The chromosome pairs separate into two different cell. The sex cells that form later have only half as many chromosomes as the other cells in the organism.