Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

AP Biology > Meiosis > Flashcards

Meiosis Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

Define homologous chromosomes

A

a pair of chromosomes that code for the same trait

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How many homologous chromosomes are in humans?

A

23

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a karyotype

A

an ordered display of the pairs of homologous chromosomes from a cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

are called X and Y

A

sex chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are autosomes

A

The 22 pairs of chromosomes that do not determine sex (determine everything else)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What does meiosis make

A

four haploid (n) gametes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is a zygote

A

Egg and sperm united to form a diploid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the longest phase of meiosis?

A

Prophase I

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What two main things happen in prophase I?

A

Synapsis

Crossing over

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is synapsis?

A

homologous chromosomes pair up

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is a tetrad

A

Sister chromatids connnected to other homologous sister chromatids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is crossing over

A

homologous chromosomes exchange DNA while connected as tetrads

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

The point at which homologous chromosomes connect to exchange DNA is called the ______

A

Chiasma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

In metaphase I, tetrads line up at the __________ _____

A

metaphase plate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is independent assortment

A

homologous chromosomes line up randomly on any side

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

In anaphase I, what happens to the tetrads?

A

tetrads separate (homologous chromosomes are separated)

17
Q

In anaphase I, what happens to the sister chromatids?

A

they remain attached at the centromere and move as one unit toward the pole

18
Q

Crossing over

produces ________ chromosomes

A

recombinant

19
Q

Define recombinant chromosomes

A

new combinations of chromosomes, which combines genes inherited from each parent

20
Q

How is prophase II of meiosis II similar to mitosis?

A

spindle fibers and kinetochores form

21
Q

How is metaphase II of meiosis II similar to mitosis?

A

chromatids line up

22
Q

How is anaphase II of meiosis II similar to mitosis?

A

chromatids are separated into individual chromosomes

23
Q

How is telophase II and cytokinesis of meiosis II similar to mitosis?

A

each cell splits, and nuclei reform (4 unidentical haploid cells are now present)

24
Q

What three mechanisms contribute to genetic variation?:

A

Independent assortment of chromosomes
Crossing over
Random fertilization

25
Q

Describe independent assortment of chromosomes

A

The number of combinations possible when chromosomes assort independently into gametes is 2^n, where n is the haploid number

26
Q

How does random fertilization add genetic variation

A

any sperm can fuse with any egg

27
Q

An egg and sperm can make about __ _______ diploid combinations

A

70 trillion

28
Q

Describe three events that occur during meiosis I but not mitosis

A
  1. Synapsis and crossing over in prophase I: Homologous chromosomes physically connect and exchange genetic information
  2. At the metaphase plate, there are paired homologous chromosomes (tetrads), instead of individual replicated chromosomes
  3. At anaphase I, it is homologous chromosomes, instead of sister chromatids, that separate

AP Biology (38 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions