Describe how is mitosis different in prokaryotic versus ... Describehow is mitosis different in...
Transcript of Describe how is mitosis different in prokaryotic versus ... Describehow is mitosis different in...
Warm-UpDescribe how is mitosis different in prokaryotic versus eukaryotic cells?Hint: go back to the difference between prokaryotes and eukaryotes during replication.
Yesterday’s Picture UNIT
3B
Meiosis UNIT
3C
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UNIT
3CMeiosis
4-chromosome somatic cell with a maternal (m) and a paternal (p)
homologue of each chromosome
2nn = 4
1m
1p
2p 2m
3p
3m 4m
4p
Meiosis starts with a somatic cell (non-gamete) which has a paternal copy and a maternal copy of each chromosome (“homologous” chromosomes).
1m 1p
2p 2m
3p 3m
4m 4p
UNIT
3CMeiosis
4-chromosome somatic cell with a maternal (m) and a paternal (p)
homologue of each chromosome
2nn = 4
1m
1p
2p 2m
3p
3m 4m
4p
Chromosome pairs line up randomly prior to division: homologues can be on either side.
Chromosome pairs line up in the middle of the cell randomly; the maternal
homologue can be either on one side or another for each chromosome.
2nn = 4
Meiosis starts with a somatic cell (non-gamete) which has a paternal copy and a maternal copy of each chromosome (“homologous” chromosomes).
UNIT
3CMeiosis
Chromosome pairs line up randomly prior to division: homologues can be on either side.
Meiosis starts with a somatic cell (non-gamete) which has a paternal copy and a maternal copy of each chromosome (“homologous” chromosomes).
1m 1p
2p 2m3p
3m
4m 4p
1p2m 3m
4p
1m2p3p
4m
Two genetically distinct gametes are born. Each have only four
chromosomes, not paired.
1nn = 4
Cell divides into two, each with of the four chromosomes, but different
combinations of homologues.
2nn = 4
Cell division causes each new cell to have different combinations of chromosomes.
Illustrate how a single somatic cell with 2 chromosomes can generate four genetically distinct gametes by drawing the process of meiosis. (LO 3.9)
CTQ #1UNIT
3C
UNIT
3CMeiosis is a process of producing gametes (sperm and egg).
Meiosis
UNIT
3CMeiosis is a process of producing gametes (sperm and egg).
Meiosis
Purpose: to increase genetic diversity during sexual reproduction.
Maize
UNIT
3CMeiosis is a process of producing gametes (sperm and egg).
Meiosis
How? by:1. Sharing genes with
another individual (sex).
Purpose: to increase genetic diversity during sexual reproduction.
UNIT
3CMeiosis is a process of producing gametes (sperm and egg).
Meiosis
How? by:1. Sharing genes with
another individual (sex).2. Making gametes as
genetically distinct from each other as possible.
Purpose: to increase genetic diversity during sexual reproduction.
I know they don’t look different, but they are!
UNIT
3CMeiosis is a process of producing gametes (sperm and egg).
Meiosis
How? by:1. Sharing genes with
another individual (sex).2. Making gametes as
genetically distinct from each other as possible.
3. Crossing over during meiosis.
Purpose: to increase genetic diversity during sexual reproduction.
UNIT
3CMeiosis
1m 1p
2p 2m
3p 3m
4m 4p
How? by:1. Sharing genes with
another individual (sex).2. Making gametes as
genetically distinct from each other as possible.
3. Crossing over during meiosis.
Purpose: to increase genetic diversity during sexual reproduction.
Crossing over creates even new combinations of maternal-paternal DNA.
UNIT
3CMeiosis
1p2m 3m
4p
1m2p3p
4m
1m 1p
2p 2m
3p 3m
4m 4p
How? by:1. Sharing genes with
another individual (sex).2. Making gametes as
genetically distinct from each other as possible.
3. Crossing over during meiosis.
Purpose: to increase genetic diversity during sexual reproduction.
Crossing over creates even new combinations of maternal-paternal DNA.
Explain how meiosis contributes to increased genetic diversity in a population. (LO 3.10)
CTQ #2UNIT
3C
State two events during meiosis that contribute to increased genetic diversity and describe how they function to increasing variation in a population. (LO 3.28)
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