Ch 7: Mitosis and Meiosis

Question 1

After interphase, a human cell has a total of __ chromosomes, each made up of two ______.

Answer 1

46, chromatids

Question 2

During the stage called interphase, how many of the cell’s chromosomes replicate?

Answer 2

All

Question 3

Each chromosome has a _______ at its center that joins the chromatids together

Answer 3

centromere

Question 4

Is DNA replication the only process that takes place during interphase?

Answer 4

No, it is one of the many processes

Question 5

Before a cell undergoes mitosis, what phase does it go through?

Answer 5

Interphase, in which chromosomes replicate

Question 6

What are the 4 steps of mitosis?

Answer 6

Prophase
Metaphase
Anaphase
Telophase

Question 7

What happens in prophase?

Answer 7

Centrioles separate and begin forming a spindle fiber apparatus called the mitotic spindle

Question 8

What happens in metaphase?

Answer 8

Centrioles go to opposite poles, chromosomes line up at the equator, and spindle fibers attach to centromeres

Question 9

What happens in anaphase?

Answer 9

spindle fibers shorten and pull chromatids to opposite poles

Question 10

What happens in telophase?

Answer 10

A nuclear membrane forms in each new cell, chromosomes uncoil and condense

Question 11

What happens in cytokinesis?

Answer 11

Cytoplasm divides

Question 12

Where does mitosis occur in plant cells?

Answer 12

Meristems- certain growing regions

Question 13

During which phase do the cell’s chromosomes become visible?

Answer 13

Prophase

Question 14

The spindle apparatus forms during a stage called _________

Answer 14

Prophase

Question 15

The division of the cell’s cytoplasm is known as ________ and occurs during _________.

Answer 15

Cytokinesis, telophase

Question 16

Chromatids separate from each other and move to opposite poles of the cell during what stage?

Answer 16

Anaphase

Question 17

During what stage do all of a cell’s chromosomes replicate?

Answer 17

Interphase

Question 18

The centromeres divide during what stage?

Answer 18

Anaphase

Question 19

During prophase, the ________ move away from one another toward opposite sides of the cell.

Answer 19

Centrioles

Question 20

What is a gene?

Answer 20

A portion of a chromosome that produces one protein

Question 21

What is gene expression?

Answer 21

When a gene creates a protein

Question 22

What is a gamete?

Answer 22

A sex cell

Question 23

What is a diploid cell?

Answer 23

A cell that has 2 complete sets of chromosomes

Question 24

What is a haploid cell?

Answer 24

A cell that has only 1 set of chromosomes

Question 25

What are the only human cells that are haploid?

Answer 25

Sperm and ovum

Question 26

What is a zygote?

Answer 26

The cell that is formed when chromosomes from the sperm join with the chromosomes in the ovum

Question 27

The zygote is ______, so it must undergo ______

Answer 27

diploid, meiosis

Question 28

What is synapsis?

Answer 28

When homologous chromosomes pair up in meiosis

Question 29

When does synapsis occur?

Answer 29

Prophase I

Question 30

In prophase I, instead of 46 replicated chromosomes, there are ______.

Answer 30

23 pairs of replicated chromosomes

Question 31

When does crossing over take place and what is it?

Answer 31

prophase I, segments on homologous chromosomes are exchanged

Question 32

What happens in metaphase in both meiosis and mitosis?

Answer 32

Chromosomes line up on the equator of the cells

Question 33

What is independent assortment of chromosomes?

Answer 33

The random way that chromosomes line up during metaphase, which affects the outcome of the genetic information in the gametes that form.

Question 34

What are linked genes?

Answer 34

Genes that are on the same chromosome and are inherited together

Question 35

What separates in mitosis and meiosis? What happens in both?

Answer 35

Mitosis- chromatids of each chromosome separate Meiosis- homologous pairs separate Move to opposite poles of the cell

Question 36

What happens in telophase I?

Answer 36

The cells finish dividing their cytoplasm, and nuclear membranes reform. The 2 new cells have 23 REPLICATED CHROMOSOMES not 23 homologous pairs

Question 37

Meiosis II is virtually identical to _______.

Answer 37

Mitosis, except in mitosis the cell starts with 46 replicated chromosomes and in meiosis, it has only 23 replicated chromosomes.

Question 38

What is the difference between mitosis and the second round of meiosis?

Answer 38

In interphase II, the chromosomes do not replicate

Question 39

If the diploid number of chromosomes is 10, then the haploid number is _

Answer 39

5

Question 40

Metaphase I of meiosis differs from metaphase of mitosis in that a _____ of chromosomes lines up on each spindle fiber.

Answer 40

pair

Question 41

The four cells resulting from meiosis are _____.

Answer 41

Haploid

Question 42

What refers to a cell for which each chromosome does not have a homologous partner?

Answer 42

Haploid

Question 43

Anaphase I of meiosis differs from anaphase of mitosis in that centromeres _____ divide

Answer 43

do not

Question 44

Prophase I of meiosis _____ similar to prophase of mitosis

Answer 44

Is not

Question 45

The cells produced at the end of telophase I are considered to be ______

Answer 45

haploid

Question 46

How many mature sperm are produced from a single spermatogonium?

Answer 46

4

Question 47

How many mature ova are produced from a single primary oocyte?

Answer 47

1

Question 48

Spermatogenesis takes place on a _____ basis, whereas oogenesis takes place on a ______ basis.

Answer 48

daily, monthly

Question 49

The cells that disintegrate during oogenesis are called ________.

Answer 49

polar bodies

Question 50

A cell that undergoes meiosis will yield how many cells?

Answer 50

4

Question 51

What is the diploid cell that starts spermatogenesis called and where does it live?

Answer 51

spermatogonium, seminiferous tubules

Question 52

What are the 3 causes of variation among offspring?

Answer 52

1. Independent assortment of chromosomes during metaphase I of meiosis 2. Crossing over during synapsis in Prophase I of meiosis 3. Random fertilization