chapter 6 pt 2 study guide

Question 1

What term is given to the specific location of genes on a chromosome?

Answer 1

locus

Question 2

What are alternative forms of a gene called?

Answer 2

allele

Question 3

How many alleles do cells have for each gene?

Answer 3

two

Question 4

Which type of allele is expressed when 2 different alleles or 2 dominant alleles are present on a chromosome?

Answer 4

Dominant

Question 5

Which type of allele is expressed when 2 copies of a recessive allele are present on a chromosome?

Answer 5

recessive

Question 6

What is commonly done by scientists while studying genetics?

Answer 6

Focusing on a single trait or set of traits

Question 7

esides genotype, what also interacts with genes and affects their expression?

Answer 7

The environment

Question 8

hat was the profession of R.C. Punnett?

Answer 8

Poultry geneticist

Question 9

What type of system did Punnett develop for predicting all possible genotypes resulting from a genetic cross?

Answer 9

grid

Question 10

By counting the number of squares in a genetic combination, what can be figured concerning genotypes?

Answer 10

Ratio of
genotypes in that generation

Question 11

What process restores the diploid number in offspring?

Answer 11

fertilization

Question 12

List the three types of monohybrid crosses.

Answer 12

Homozygous x homozygous,
heterozygous x heterozygous,
and heterozygous x
homozygous

Question 13

List the three types of monohybrid crosses.

Answer 13

Homozygous x homozygous,
heterozygous x heterozygous,
and heterozygous x
homozygous

Question 14

What type of phenotype must an organism have in order for a testcross to be necessary?

Answer 14

Recessive phenotype

Question 15

What was the phenotypic ratio that Gregor Mendel consistently obtained in the second generation of breeding?

Answer 15

9:3:3:1

Question 16

What name is given to Mendel’s second law of genetics?

Answer 16

Law of independent assortment

Question 17

According to the law of independent assortment, how do allele pairs separate during meiosis?

Answer 17

Independently of each
other

Question 18

Which type of outcomes are predicted through the use of the mathematics called probability?

Answer 18

Genetic

Question 19

What is a major advantage of sexual reproduction that is produced within a species?

Answer 19

great genetic variation

Question 20

In the formation of gametes, how many different possible human chromosome combinations are there?

Answer 20

8 million

Question 21

What are mixed during the joining of gametes during fertilization?

Answer 21

alleles

Question 22

How many possible genetic combinations are there in the joining of two human gametes?

Answer 22

70 trillion

Question 23

What is ensured for organisms through sexual reproduction?
What does this result in for the organism?

Answer 23

A unique combination of genes
Unique phenotypes

Question 24

What is another term for the process of ensuring genetic diversity called crossing over?

Answer 24

recombination

Question 25

When does crossing over occur?

Answer 25

During prophase I of meiosis I

Question 26

What affects the likelihood of whether genes are separated when crossing over happens?

Answer 26

How far apart two genes are on the chromosome

Question 27

Which kind of genes tend to be inherited together?

Answer 27

Genes located close together

Question 28

What have scientists been able to build for many species by exploring relationships between many genes?

Answer 28

Genetic map