Meiosis Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What is meiosis?

A

making gametes

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

What are gamets?

A

egg and sperm ( s*x cells)

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

What is asexual reproduction?

A

binary fission, budding, and regeneration are used by plants and animals to reproduce asexually through mitosis. Produces IDENTICAL copies of paretn cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q
  • faster
  • doesn’t need a partner
    are …
A

advantages of asexual reproduction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q
  • all ALIKE
  • species can’t change and adopt
    -one disease can wipe out a whole popultation
    are…
A

disadvantages of asexual reproduction

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

What is sexual reproduction?

A

combines genetic material from 2 parents ( sperm and egg) so offspring are genetically different from paretn

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q
  • allows for variation in population
  • allow species to adopt to canges in environment
    are…
A

advantages of sexual reproduciton

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

What is another word for body cells?

A

somatic cells

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

Body cells ( somatic cells) have ____ copies of each chromosome= diploid ( 2n) ( one from mom and one from dad)

A

2 copies

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

All sperm and egg cells are

A

haploid(1n)

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

s*x cells have only ___ copy of each chromosome

A

one copy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q
  • makes 2 cells genetically identical to parent cell and to each other
    0 used by organisms to increase size of organism, repair inguries, repalce worn out cells
A

mitosis creates diploid body cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q
  • makes 4 cells genetically different from paretn cell and from each other
  • used for sexual reproduction
A

meiosis creates haploid sex cell

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

What are the two steps Meiosis takes place in?

A

1) Meiosis I : IPMAT
2) PMAT

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

DNA replicates creating hmologous chromosomes

A

interphase I

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q
  • Homologous chromosomes pair up = synapsis
  • this group of FOUR (4) chromatids is called a =tetrad
A

Prophase I

17
Q

Homologous chromosomes pair up

A

synapsis

18
Q

This group of FOUR (4) chromatids is called a

A

tetrad

19
Q
  • exchange of DNA between homoglous pairs
    -allows for rearranging of DNA in different combinations
  • after crossin gover, chromatid arms are NOT identical anymore
A

crossing over

20
Q

tetrads line up in the middle

A

metaphase 1

21
Q

tetrads pull apart to opposite ends of the cell

A

anaphase 1

22
Q

cell separates into 2 new cells

A

telophase 1

23
Q

No interphase II which means chromosomes are NOT copied again

A

Meiosis II

24
Q

2 cells begin meiosis II

A

Prophase II

25
Q

Chromosomes line up in the middle of the cell

A

Metaphase II

26
Q

Chomarids are pulled to opposite ends of the cel

A

Anaphase II

27
Q

The 2 cells divide to form 4 genetically different cells (gametes )

A

Telophase II / cytokinesis

28
Q

End result of meiosis

A
  • 4 new cells
  • half number of chromosomes ad parent cell ( haploid )
  • humans 23 chromosomes
29
Q

Spermatogenesis

A

Making mature sperm

30
Q
  • spermatogenesis
  • mature and grow flagella
  • 4 sperms
A

Male

31
Q

Oogenesis

A

Making a mature egg

32
Q
  • oogenesis
  • produced :1 “good “ egg and 3 polar bodies
  • cytoplasm divides unevenly ; polar bodies degenerate ( die )
A

Female

33
Q

Why make only one “good egg “

A
  • sperm donated mostly DNA
  • most of the cell parts and nutrients needed for baby come from egg !