CH.7 Flashcards
Know the difference between mitosis and meiosis
Mitosis is shown to produce 2 identical daughter cells vs. meiosis is where a single cell divides twice to produce 4 cells
Know all the phases of meiosis and what happens during each phase
Interphase
Prophase 1
Prometaphase 1
Metaphase 1
Anaphase 1
Telophase 1
Cytokenesis
Prophase 2
Prometaphase 2
Metaphase 2
Anaphase 2
Telophase 2
Know the cells in which mitosis and meiosis take place
Meiosis- Plant, animal and fungi
Mitosis- all organisms except virus
Know the meaning of homologous chromosomes
A pair of chromosomes made up of two homologs. Homologous chromosomes have corresponding DNA sequences and come from separate parents; one homolog comes from the mother and the other comes from the father.
Know the outcome of meiosis
Outcome: Four sex cells
Know what crossing over and independent assortment means and at what stage of meiosis they happen, know that they contribute to genetic variability
In prophase #1
crossing over occurs.
Crossing over
exchanging genetic material between homologous pairs of chromosomes
In metaphase #1
independent assortment occurs.
Independent assortment
produces 2n distinct
gametes, where n = the number of unique
chromosomes.
2. In humans, n = 23 and 223 = 8,388,608
combinations!
Know about errors in meiosis
Non disjunctions, Duplications, and
Deletions
Euploid
An individual with the appropriate
number of chromosomes
Aneuploid
An individual with an error in
chromosome number.
Monosomy loss of one chromosome
Trisomy gain of an extraneous chromosome.
Know about chromosomal abnormalities
disorder characterized by a morphological or numerical alteration in single or multiple chromosomes, affecting autosomes, sex chromosomes, or both.
