Chapter 13

Question 1

What is the process that results in formation of haploid gametes (egg and sperm)?

Question 2

Define fertilization.

Question 3

What does a karyotype show?

Question 4

What are the sex chromosomes in humans? What codes for female? What codes for male?

Question 5

What are the chromosomes that code for traits other than sex determination called?

Question 6

What are chromosomes of the same type (homologs that code for the same genes, however versions of the genes may differ) called?

Question 7

Define gene.

Question 8

Define haploid and diploid, and include their symbols.

Question 9

What is the vocabulary for an organism with three or more versions of each type of
chromosome?

Question 10

What is the overall result of meiosis?

Question 11

After replication has occurred in the parent cell, how many chromosomes are there total?

Question 12

What is the difference between the results of meiosis I and meiosis II?

Question 13

Define gametogenesis.

Question 14

Does a zygote undergo meiosis or mitosis?

Question 15

List the five phases of meiosis I, in order.

Question 16

Define when the homolog pairs come together in a pairing process. In what stage does this occur?

Question 17

Name the structure that results from synapsis.

Question 18

Are the chromatids between the paternal and maternal chromosomes identical?

Question 19

What is the network of proteins that holds non-sister chromatids together along their entire length?

Question 20

During which phase does crossing over occur? Explain crossing over.

Question 21

Summarize metaphase I, anaphase I, and telophase I.

Question 22

Summarize the results of meiosis I.

Question 23

List the four phases of meiosis II, in order.

Question 24

Summarize the four stages of meiosis II.

Question 25

Summarize the results of meiosis II.

Question 26

What are the three ways that genetic variation can occur in sexual reproduction?

Question 27

Are the offspring from asexual reproduction genetically variable?

Question 28

What is the most significant result of sexual reproduction? (Hint: Asexual reproduction severely lacks this and suffers greatly!)

Question 29

Define nondisjunction. What is the result?

Question 30

Define when a gamete lacks a chromosome.

Question 31

Define when a gamete has an extra copy of a chromosome.

Question 32

What is an important factor correlated with the frequency of trisomy 21?