Meiosis Flashcards
What is reduction division?
Starting cell that has 46 chromosomes and ending cells that only have 23 chromosomes
Where does Meiosis occur in males and females?
Testes and Ovaries
What happens in Prophase I?
Early prophase
Homologs pair.
Late prophase
Chromosomes condense.
Crossing over occurs.
Spindle forms.
Nuclear envelope fragments.
What is the forming of two sister chromatids called?
A tetrad.
What is crossing over?
Homologous
chromosomes in a
tetrad cross over each
other
Pieces of
chromosomes or
genes are exchanged
Produces Genetic
recombination in the
offspring
What happens in Metaphase I?
Centrosomes are at opposite
sides of the cell.
Microtubules attach to the
centromere/kinetochores
What is the Law of Independent Assortment?
What is the Law of Segregation?
What is the Law of Dominance?
A dominant allele will always yield the dominant trait when combined with a recessive allele.
What happens in Anaphase I?
Homologs separate and move
to opposite poles.
Sister chromatids remain
attached at their centromeres.
What happens in Cytokinesis i?
Chromosomes completely uncoil to become chromatin
Nuclear membrane completely reforms
What happens in Telophase I?
Nuclear envelopes reassemble.
Spindle disappears.
Cytokinesis divides cell into
two.
Cells are now haploid (n)
What happens in Interphase II?
Cell prepares for division
Chromatin begin to coil/condense into
chromosomes
DNA is NOT DUPLICATED so it
remains a haploid (n)
What happens in Prophase II?
Nuclear envelope
fragments.
Chromosomes condense
Spindle forms.
No crossing over
What happens in Metaphase II?
Chromosomes line up at the
center of the cell (no longer in
pairs)
Independent assortment occurs
again (of the sister chromatids
Microtubules attach to
centromere/kinetochore
