Chapter 8: Mendel and Genetics

Question 1

Dominant

Answer 1

The trait will be displayed even if only one factor specifying it is present

Question 2

Recessive

Answer 2

The trait will be displayed only in the absence of the dominant

Question 3

Allele

Answer 3

The different forms of a gene

Question 4

Homozygous

Answer 4

Having two identical alleles (dominant or recessive) for a trait

Question 5

Heterozygous

Answer 5

Having two different alleles (one dominant and one recessive) for a trait

Question 6

Genotype

Answer 6

An organism’s individual collection of genes (allele combination)

Question 7

Phenotype

Answer 7

The physical traits that appear in an individual as a result of its genotype and from the environment

Question 8

Monohybrid Cross

Answer 8

a genetic cross that involves one pair of contrasting alleles for a trait

Question 9

Gene

Answer 9

The set of information that controls a trait; a segment of DNA on a chromosome that codes for a specific trait

Question 10

Incomplete Dominance

Answer 10

A blended phenotype. One allele is not completely dominant over the other

Question 11

Chromosomes

Answer 11

Coiled chromatin, 46 are found in human body cells

Question 12

Diploid

Answer 12

Two copies of each gene

Question 13

Haploid

Answer 13

One copy of each gene

Question 14

Testcross

Answer 14

A way to determine the genotype of an individual with an unknown dominant phenotype using a homozygous recessive individual

Question 15

Gametes

Answer 15

Sex cells; eggs and sperm

Question 16

Sex-linked

Answer 16

when traits are determined by alleles on the sex chromosomes

Question 17

The Law of Segregation

Answer 17

When any individual produces gametes, the two copies of a gene separate, so each gamete receives only one copy

Question 18

Punnett Square

Answer 18

A chart that shows all possible combinations of alleles that can result from a genetic cross

Question 19

Punnett Square box

Answer 19

Where the genotypes of haploid gametes from one parent are on the horizontal axis, and the genotypes of the other parent are on the vertical axis

Question 20

Dihybrid cross

Answer 20

a genetic cross that involves two pair of contrasting alleles for traits

Question 21

Law of Independent Assortment

Answer 21

Where alleles of different genes assort independently of one another during gamete formation

Question 22

Genotype Ratio

Answer 22

The ratio of genotypes that could appear in offspring

Question 23

Phenotype Ratio

Answer 23

the ratio of phenotypes that could appear in offspring

Question 24

Codominance

Answer 24

When two alleles of a gene both produce their phenotypes when present in a heterozygote

Question 25

Cytoplasmic Inheritance

Answer 25

Present for organelles with their own genomes (mitochondria and chloroplasts)

Question 26

Non-Mendelian Inheritance

Answer 26

is any pattern of inheritance in which traits do not segregate in accordance with Mendel’s laws

Question 27

Locus (loci)

Answer 27

is the location of a certain gene on a chromosome

Question 28

Artificial Selection

Answer 28

Is the process of humans selectively breed plants and animals

Question 29

Polygenic Inheritance

Answer 29

Is when the phenotype of a heterozygote contains the products of both alleles