MEIOSIS Flashcards
1
Q
- MEIOSIS ONE ?
A
- it is the base of any sexual reproduction .
2
Q
- what happen in meiosis ?
A
- the gametes have haploid number of chromosomes ,
- then the gametes becomes a diploid number of chromosomes during a process called “ fertilization “ .
- then we can have the “ zygote “ .
3
Q
- what is the “ zygote “ ?
A
- its the complete process of the fertilization
- haploid-sperm + haploid-egg = diploid-zygote .
4
Q
- what is the “ replication of chromosomes “ ?
A
- its the process of DNA´s synthesis and condensation
- un replicated chromosome —- DNA synthesis and condensation —- “DYAD” 2 sister chromatids .
5
Q
- where does the sister chromatids connect ?
A
- the sister chromatids are connected in the centromere area .
6
Q
- when does the replication occurs ?
A
- the replication occurs in the interphase during S-phase .
7
Q
- stages of meiosis one/two ?
A
- prophase one/two
- metaphase one/two
- anaphase one/two
- telophase one/two
8
Q
- early prophase one ?
A
- chromosomes becomes in pairs
- crossing over occurs
- chiasmata “ its an exchange of the genetic-info between both chromatids “ ( genetic recombination ) .
9
Q
- late prophase one ?
A
- chromosomes becomes condense ,
- appearance of spindle strings/fibers ,
- nuclear envelope fragments .
10
Q
- metaphase one ?
A
- spindle fibers begins to capture the homologous pairs of chromosomes ,
- homologous pairs are organized in the center .
11
Q
- anaphase one ?
A
- homologous chromosomes separate and move into opposite poles .
- the sister chromatids remain connection at their centromeres .
12
Q
- telophase one ?
A
- nuclear envelopes reappear
- each group of homologous chromosomes move to the opposite pole
- spindle fibers disappears
- cytokinesis divides the cells into two .
13
Q
- MEIOSIS TWO ?
A
- meiosis ii is similar to “ mitosis “ .
- except one thing, the cells have the half number of chromosomes . ( haploid number ) .
- before meiosis two DNA replication does not occur .
- the interphase is short .
- four identical haploid cells .
14
Q
- prophase two ?
A
- nuclear envelope disappear ,
- spindle fibers forms .
15
Q
- metaphase two ?
A
- spindle fibers are connected in the centromere .
- the chromosomes are located in the meddle of the cell .
16
Q
- anaphase two ?
A
- the centromere breaks down and separate the chromatids ,
- each chromatid move into the opposite pole .
17
Q
- telophase two ?
A
- nuclear envelopes reappears ,
- four cells form in this phase .
18
Q
- what is the tetrad, when does tetrad happen exactly ?
A
- its when the chromosomes are attached ,
- in exact point called ( synapsis ) .
19
Q
- how much division in the mitosis ?
A
- there is one division .
20
Q
- how much division in the meiosis ?
A
- there is two division .
21
Q
- the number of produced cells in case of mitosis ?
A
- two produced cells .
22
Q
- the number of produced cells in case of meiosis ?
A
- four produced cells .
23
Q
- the genetic match in case of mitosis ?
A
- there is no genetic match .
24
Q
- the genetic match in case of meiosis ?
A
- there is no genetic match .
25
Q
- the number of chromosomes in case of mitosis ?
A
- complete number of chromosomes ( diploid number )
26
Q
- the number of chromosomes in case of meiosis ?
A
- the half number of chromosomes ( haploid number ) .
27
Q
- the mitosis division occur in ?
A
- the mitosis division occur in ( somatic cells ) .
28
Q
- where does the meiosis division occur ?
A
- the meiosis division occur in ( germ cells ) .
29
Q
- when does the mitosis happen ?
A
- it happen during live .
30
Q
- when does the meiosis happen ?
A
- it happen in sexual maturity .
