Ch. 12 - Introduction to Genetics Vocab

Question 1

genetics

Answer 1

• scientific study of heredity

Question 2

fertilization

Answer 2

• process in sexual reproduction in which male and female reproductive cells join to form a new cell

Question 3

trait

Answer 3

• specific characteristics of an individual

Question 4

hybrid

Answer 4

• offspring of crosses between parents with different traits

Question 5

gene

Answer 5

• sequence of DNA that codes for a protein and thus determines a trait; factor that is passed from parent offspring

Question 6

allele

Answer 6

• one of a number of different forms of a gene

Question 7

principle of dominance

Answer 7

• Mendel’s second conclusion, which states that some alleles are dominant and others are recessive

Question 8

segregation

Answer 8

• separation of alleles during gamete formation

Question 9

gamete

Answer 9

• sex cell

Question 10

probability

Answer 10

• likelihood that a particular event will occur

Question 11

homozygous

Answer 11

• having two identical alleles for a particular gene

Question 12

heterozygous

Answer 12

• having two different alleles for a particular gene

Question 13

phenotype

Answer 13

• physical characteristics of an organism

Question 14

genotype

Answer 14

• genetic makeup of an organism

Question 15

Punnett square

Answer 15

• diagram that can be used to predict the genotype and phenotype combinations of a genetic cross

Question 16

independent assortment

Answer 16

• one of Mendel’s principles that states that genes for different traits can segregate independently during the formation of gametes

Question 17

incomplete dominance

Answer 17

• situation on which one allele is not completely dominant over the other allele

Question 18

codominance

Answer 18

• situation in which the phenotypes produced by both alleles are completely expresses

Question 19

multiple alleles

Answer 19

• a gene that has more than two alleles

Question 20

polygenic trait

Answer 20

• trait controlled by two or more genes

Question 21

homologous

Answer 21

• term used to refer to chromosomes in which one set comes from the male parent and one set comes from the female parent

Question 22

diploid

Answer 22

• term used to refer to a cell that contains two sets of homologous chromosomes

Question 23

haploid

Answer 23

• term used to refer to a cell that contains only a single set of genes

Question 24

meiosis

Answer 24

• process in which the number of chromosomes per cell is cut in half through the separation of homologous chromosomes in a diploid cell

Question 25

tetrad

Answer 25

• structure containing four chromatids that forms during meiosis

Question 26

crossing over

Answer 26

• process in which homologous chromosomes exchange portions of their chromatids during meiosis