Lecture 11- Meiosis

Question 1

What are autosomes/somatic cells?

Answer 1

Any chromosome that is not a sex chromosome

Question 2

How many autosomes do humans have?

Answer 2

23 pairs-> 44 total autosomes

Question 3

Are somatic cells haploid or diploid?

Answer 3

Diploid (2n)

Question 4

What are the sex chromosomes for a male human?

Answer 4

XY

Question 5

What are the sex chromosomes for a female human?

Answer 5

XX

Question 6

From when to when does the human life cycle occur?

Answer 6

From conception to production of offspring

Question 7

What ploidy change occurs during fertilization?

Answer 7

Haploid (n) + Haploid (n) → Diploid (2n)

Question 8

What does fertilization result in?

Answer 8

Zygote

Question 9

What ploidy change occurs during meiosis?

Answer 9

Diploid (2n) → haploid (n) [ploidy is halved]

Question 10

What is the overall goal of meiosis?

Answer 10

Produce 4 genetically unique daughter cells

Question 11

How many chromatids are present in a human somatic cell following interphase?

Answer 11

92

Question 12

When does ploidy change during meiosis?

Answer 12

Anaphase I

Question 13

What is the longest stage of meiosis?

Answer 13

Prophase I

Question 14

When does chromosomal crossover occur?

Answer 14

Prophase I

Question 15

What is synapsis?

Answer 15

Process by which homologous chromosomes pair up and form a tetrad

Question 16

What is the name of a chromosome that has undergone crossing-over?

Answer 16

Recombinant chromosome

Question 17

What occurs during anaphase I?

Answer 17

Homologous chromosomes separate (disjunction)

Question 18

True or False: Cells are still diploid (2n) following meiosis I

Answer 18

False; following meiosis I, each cell is haploid (n)

Question 19

True or False: Cells undergo interphase following meiosis I, before proceeding to meiosis II

Answer 19

False; cells only go through interphase once per cycle

Question 20

True or False: Crossing-over occurs once more during prophase II

Answer 20

False; chromosomal crossover only occurs during prophase I

Question 21

What occurs during anaphase II?

Answer 21

Sister chromatids are separated

Question 22

True or False: A homologous pair is two sister chromatids joined at the centromere

Answer 22

False; a homologous pair consists of one maternal chromosome and one paternal chromosome