Meiosis Flashcards
How many daughter cells does meiosis create?
4
what type of cell division is meiosis?
sexual
what does meiosis produce?
four haploid gametes that are all genetically different
What are gametes?
Sex cells (sperm and egg)
What is a diploid cell?
A cell with a full set of chromosomes
What is a haploid?
A cell with a half set of chromosomes.
What symbol can represent diploid cells?
2N
What symbol can represent haploid cells?
N
What are homologous pairs?
Chromosomes that are the same size
What is crossing over?
the process of sections of non-sister chromatids exchanging
When does crossing over occur?
Prophase 1
What do homologous chromosomes create when they pair up?
tetrad
how many phases of PMAT does meiosis go through?
2
what is the order of meiosis?
P1,M1,A1,T1, cytokenisis, P2,M2,A2,T2
do chromosomes cross over in prophase 2?
no
what happens during prophase 1?
chromosomes double and thicken. the nuclear membrane disappears, crossing over occurs
what happens during metaphase 1?
homologous pairs of chromosomes line up at the center of the cell. spindle fibers attach
what happens during anaphase 1?
chromosomes pairs separate and move to opposite sides of the cell.
what happens during telephase 1?
two new cells are formed with the same number of chromosomes
what happens during prophase 2?
the nuclear membrane disappears. chromosomes do not double
what happens during metapahse 2?
duplicated chromosomes line up along the center of the cell
what happens during anaphase 2?
chromosomes split at the middle and chromatids are pulled to opposite sides of the cell
what happens during telephase 2?
Four new cells are formed. each daughter cell has half of the number of chromosomes as the original
what does crossing over help create?
genetic variation
what is the difference from prophase 1 from prophase 2?
In prophase 2, there are no homologous pairs and no crossing over
what is the difference from metephase 1 from metaphase 2?
In metaphase 2, duplicated chromosomes line up, NOT homologous chromosomes.
when a sperm fertilizes an egg, when does it create?
a zygote
Does meiosis create haploid or diploid cells?
Haploid