Life Science: Meiosis Flashcards
Q: What is meiosis?
A: Cell division to create haploid gametes in diploid organisms
Q: What happens during Prophase I?
A: As the nuclear envelope breaks down, chromosomes condense and form homologous pairs. Homologous pairs will crossover and exchange DNA at random. Centrioles move to opposite poles, spindle fibers begin to form mitotic spindles (made from microtubules).
Which stage of meiosis I do chromosomes condense and form homologous pairs?
Prophase I
Which stage of meiosis I do homologous pairs crossover and exchange DNA?
Prophase I
Q: What happens during Metaphase I?
A: Spindle fibers attach to homologous chromosomes and line up in the middle
Which stage of meiosis I has homologous chromosomes pairs lined up at the middle of the cell?
Metaphase I
Q: What happens during Anaphase I?
A: Homologous chromosomes separate to opposite sides of the cell by spindle fibers.
Which stage of meiosis I are homologous chromosomes are separates to opposites side of the cell?
Anaphase I
Q: What happens during Telophase I?
A: Nuclear membrane forms as a cell separates into haploid daughter cells with chromosomes consisting of two sister chromatids.
What stage in meiosis I does a nuclear envelope form and chromosome decondense?
Telophase I
Q: What happens during Prophase II?
A: As the nuclear envelope breaks down, Haploid daughters’ cells condense and contain half the chromosomes from the original cell. Centrioles move to opposite poles, spindle fibers begin to form mitotic spindles (made from microtubules).
What stage in meiosis II do chromosomes condense?
Prophase II
Q: What happens during Metaphase II?
A: Spindle fibers attach to chromosomes that are independently assorted and line up in the middle.
what stage in meiosis II do chromosomes align at the center of the cell?
Metaphase II
Q: What happens during Anaphase II?
A: Sister chromatids separate to opposite sides of the cell (towards poles) by spindle fibers (coming from centriole).
what stage in meiosis II seperates the sister chromatids to the poles of the cell?
Anaphase II
Q: What happens during Telophase II?
A: Nuclear membrane forms as the two daughter cells from meiosis I separate into four haploid daughter cells with chromosomes consisting of a single chromatid.
What stage of meiosis II forms a nuclear membrane and chromosomes decondense?
Telophase II
Q: How does meiosis contribute to genetic diversity?
A: Meiosis increases genetic diversity through crossing over during Prophase I and Independet assormtment in Metaphase I (homologous pairs line up randomly)
What is crossing over? When does crossing over occur?
The exchange of genetic material between two homologous chromosomes during Prophase I.
