Biology Chapter 11

Question 0

What happens when pollen fertilizes an egg cell?

Answer 0

A seed for a new plant is born

Question 1

What is genetics?

Answer 1

The scientific study of heredity

Question 2

What does the phrase true-breeding mean?

Answer 2

If a plant is allowed to self-pollinate, it will produce offspring identical to itself

Question 3

How did Mendel prevent plants from self-pollinating?

Answer 3

He cut away parts that produce pollen and dusted pollen from one plant to another

Question 4

What are specific characteristics that vary from one individual to another?

Answer 4

Traits

Question 5

What are genes?

Answer 5

Chemical factors that determine traits

Question 6

What are the offspring crosses between parents with different traits called?

Answer 6

Hybrids

Question 7

What are alleles?

Answer 7

The different forms of a gene

Question 8

What does the principle of dominance mean?

Answer 8

Some alleles are dominant while others are recessive

Question 9

True or false: In Mendel’s pea plants, tall and yellow were controlled by dominant alleles.

Answer 9

True

Question 10

About how many of Mendel’s F2 generation showed a recessive trait?

Answer 10

1/4

Question 11

What are gametes?

Answer 11

Sex cells that, when produced, cause a segregation of a dominant and recessive allele

Question 12

What is probability?

Answer 12

The likelihood that something will occur

Question 13

True or false: Alleles do not segregate randomly.

Answer 13

False

Question 14

How do geneticists use Punnett squares?

Answer 14

To predict and compare the genetic variations that will result from a cross

Question 15

What is the difference between genotype and phenotype?

Answer 15

Genotype is the genetic makeup of an organism while phenotype is the physical characteristics

Question 16

What does it mean when a plant is homozygous or heterozygous?

Answer 16

A homozygous plant have two identical alleles for a particular trait while a heterozygous plant has two different alleles for the same trait

Question 17

True or false: Homozygous organisms are true-breeding for a particular trait.

Answer 17

True

Question 18

What was the genotype for Mendel’s true-breeding round yellow peas?

Answer 18

RRYY

Question 19

True or false: Mendel observed that genes segregate independently in the F2 generation.

Answer 19

True

Question 20

What was Mendel’s principle of independent assortment?

Answer 20

Genes for different traits can segregate independently during the formation of gametes

Question 21

What happens in incomplete dominance?

Answer 21

One allele is not completely dominant over another

Question 22

What happens during codominance?

Answer 22

Both alleles contribute to the phenotype of the organism.

Question 23

What three criteria was Thomas Hunt Morgan looking for in a model organism for genetic studies?

Answer 23

Small
Easy to keep in a laboratory
Able to produce lots of offspring in little time

Question 24

What two factors determine an organism's characteristics?

Answer 24

Genes | Interaction with the environment

Question 25

What does it mean when two sets of chromosomes are homologous?

Answer 25

Each chromosome from the female parent corresponds with the male parent

Question 26

What does 2N stand for?

Answer 26

A diploid cell

Question 27

Why is meiosis described as the process of reduction division?

Answer 27

The number of chromosomes per cell is cut in half through the separation of homologous chromosomes in a diploid cell

Question 28

What are the two distinct divisions of meiosis called?

Answer 28

Meiosis I and Meiosis II

Question 29

How many chromatids are in a tetrad?

Answer 29

4

Question 30

What results from the process of crossing-over?

Answer 30

The exchange of alleles between homologous chromosomes and produces new combinations of alleles

Question 31

What are the four phases of meiosis?

Answer 31

Prophase Metaphase Anaphase Telophase

Question 32

True or false: Sperm and egg gametes are diploid cells.

Answer 32

False (haploid)

Question 33

What are polar bodies?

Answer 33

Cells produced in females that do not produce in reproduction

Question 34

True or false: Meiosis begins with a diploid cell and produces two genetically identical diploid cells.

Answer 34

True

Question 35

True or false: Thomas Hunt Morgan discovered that all genes follow the principle of independent assortment.

Answer 35

False

Question 36

What two conclusions did Morgan make about genes and chromosomes?

Answer 36

Each chromosome is actually a group of linked genes | Mendel's principle of independent assortment still holds true

Question 37

What process sometimes separates linked genes?

Answer 37

Crossing-over

Question 38

True or false: Crossing over limits genetic diversity

Answer 38

False

Question 39

True or false: Genes that are closer are more likely to be separated by a crossover event in meiosis.

Answer 39

False

Question 40

What is a gene map?

Answer 40

A diagram that shows the relative location of each new gene