Chapter 19

Question 1

______reproduction produces individuals that are genetically distinct from their parents and siblings. _____ reproduction does not.

Answer 1

Sexual ; Asexual

Question 2

The haploid cells that fuse to create a new individual are called

Answer 2

gametes

Question 3

Cells of the body are known as ____ cells. They differ from gametes in that somatic cells are diploid (having two sets of chromosomes), while gametes are haploid (having one set of chromosomes).

Answer 3

somatic

Question 4

Humans have __ autosomes in each somatic cell and __ sex chromosomes, totaling __ chromosomes.

Answer 4

44, 2, 46

Question 5

Humans have ___ autosomes in each gamete and __ sex chromosome, totaling __ chromosomes.

Answer 5

22, 1, 23

Question 6

For chimpanzees, each somatic cell has __autosomes and __ sex chromosomes. In each gamete, they would have __autosomes and __ sex chromosome.

Answer 6

48, 2, 24, 1

Question 7

If an organism is diploid, you would expect it to reproduce

Answer 7

sexually

Question 8

Organisms that reproduce only by asexual reproduction are generally

Answer 8

not diploid

Question 9

The human ___ chromosome is larger than the ___ chromosome. Females have more genes in each cell because they have two X chromosomes. The ___ chromosome is necessary for all humans. Males have more unique genes in each cell because they possess one X and one Y chromosome.

Answer 9

X, Y, X

Question 10

The gene necessary for the production of testes is _____. If this gene is not present or has a mutation, the genital tissue develops into female structures.

Answer 10

SRY (Sex-determining Region Y)

Question 11

_____ chromosomes are the same size and have the same genes at the same positions, but are not identical (differ up to about 1%).

Answer 11

Homologous

Question 12

Sister chromatids are identical because they are the two resulting copies of a chromosome produced during

Answer 12

DNA replication.

Question 13

The same gene on two ______ chromosomes is called homologs.

Answer 13

homologous

Question 14

In humans, the cells that undergo meiosis are found in the _____ in females and the _____in males.

Answer 14

ovaries, testes

Question 15

Meiosis differs from mitosis because the cell divides ____times. The first round is called Meiosis I, and the second is called Meiosis II.

Answer 15

two

Question 16

Starting with one cell at the beginning of meiosis, there are ______ cells at the end. These resulting cells are called _______.

Answer 16

four, gametes

Question 17

During Meiosis I, _________ are separated. During Meiosis II, _______are separated.

Answer 17

homologous chromosomes, sister chromatids

Question 18

The aligning of homologous chromosomes during Meiosis I is called _______. The four chromatids bound together are known as a ______. This occurs during _________

Answer 18

synapis, tetrad, Prophase I

Question 19

In Meiosis I, 23 _______chromosomes align at the midpoint during Metaphase I.

Answer 19

homologous

Question 20

In Meiosis II, 23 ________ chromosomes align at the midpoint during Metaphase II.

Answer 20

duplicated

Question 21

Another name for a tetrad is a _______. The probability a gamete receives the maternal or paternal copy of Chromosome 12 is ____ each.

Answer 21

bivalent, 50% each

Question 22

In males, the _________ “tumbles” with the X chromosome. The probability a sperm ends up with an X chromosome is ___ and a Y chromosome is ___, matching the approximate male-to-female ratio in the population.

Answer 22

Y chromosome, 50%, 50%

Question 23

Recombination involves the cutting and attaching of two different ___ molecules. Recombination events are called ________ and occur at _______.

Answer 23

DNA, crossing over, chiasmata

Question 24

Places where homologous chromosomes overlap are called _______. The singular is ______.

Answer 24

chiasmata, chiasma

Question 25

Chiasmata undergo ________. A ________ structure is produced during the repair of these breaks.

Answer 25

double strand breaks, holiday junction

Question 26

The number of different combinations of maternal and paternal chromosomes in a human is _______, which equals ________.

Answer 26

2^23, 8,388,608

Question 27

When two genes are on the same chromosome, their inheritance will be

Answer 27

linked