Chapters 11.4, 34.3, 34.4, and 10.4 Flashcards
What is produced by meiosis?
4 haploid cells total
Describe how crossing over increases genetic diversity.
Chromosomes exchange DNA. This creates more unique chromosomes and more genetic diversity.
What happens during metaphase 1 and how is genetic diversity increased?
Spindle fibers move tetrads to the cell equator randomly which increases genetic diversity.
What is the end product after cytokinesis 1?
2 haploid cells
What determines when cytokinesis 1 begins?
The formation of the cleavage furrow
What are the two different cell types?
Somatic and sex cells
Meiosis creates more ______ and ______, while mitosis creates more
egg & sperm, body cells
What is meiosis?
A process in which our gametes (sperm & egg) reproduce
What else is meiosis called? Why?
Reduction division because the number of chromosomes is being cut in half.
What does meiosis 1 alone create?
2 haploid cells
What does interphase 1 start with?
A diploid cell (set of chromosomes from each parent)
What are the three stages of interphase and what happens in each?
G1 period of growth, S DNA replication, G2 organelles copied and preparation for division.
What all happens in prophase 1?
Centrioles begin to create spindle fibers and move to opposite poles, nuclear membrane and nucleolus break down, chromatin coils into chromosomes
What are homologous pairs?
Chromosomes that are the same size, shape, or genetic material
What’s a synapsis and what does it form?
A synapsis is when homologous chroomosomes pair up, forms a tetrad.
What is a tetrad?
4 sister chromosomes
What is crossing over and what does it do?
When homologous chromosomes wrap around each other. It also increases genetic diversity by creating unique chromosomes.
Crossing over is completely _______.
random. ex: yeet, 21
How can you tell the difference between metaphase in mitosis and meiosis?
in mitosis there is one row of chromosomes, in meiosis there are two rows of chromosomes
What happens in anaphase 1 and what is left on both sides after?
pulls the tetrads apart to both sides, one chromosome is left on each side after
What happens in telaphase 1 and what marks the end of it?
Nucleolus and nuclear membrane reform, spindle fibers break apart. Cleavage furrow marks the end of this stage.
What marks the beginning of cytokinesis and what happens in this stage?
Formation of the cleavage furrow. It is the division of the cytoplasm.
What is created after cytokinesis?
2 haploid sex cells
List two major differences between meiosis 1 and 2.
Meiosis 2 normally skips interphase 2 and goes straight to prophase 2, and DNA isn’t copied in meiosis 2