MEIOSIS and Sexual Reproduction - · PDF fileMEIOSIS and Sexual Reproduction Please submit...
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MEIOSIS and Sexual Reproduction 6.1 Meiosis Please submit the lab report at the front. Pick up new study guide and funpack.
Transcript of MEIOSIS and Sexual Reproduction - · PDF fileMEIOSIS and Sexual Reproduction Please submit...
MEIOSIS and Sexual Reproduction
6.1 Meiosis Please submit the lab report at the front. Pick up new study guide and funpack.
! 1!
Compare(the(Events(of(Mitosis(and(Meiosis(!
Meiosis(I( Mitosis(Interphase! Interphase!
Chromosome!#!Chromatid!#!Paired?!
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Prophase!I! Prophase!Chromosome!#!Chromatid!#!Paired?!
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Chromosome!#!Chromatid!#!Paired?!
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Metaphase!I! Metaphase!Chromosome!#!Chromatid!#!Paired?!
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Anaphase!I! Anaphase!Chromosome!#!Chromatid!#!Paired?!
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Chromosome!#!Chromatid!#!Paired?!
!!!!
Telophase!I! Telophase!Chromosome!#!Chromatid!#!Paired?!
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Chromosome!#!Chromatid!#!Paired?!
!!!!
Interkinesis! Cytokinesis!Chromosome!#!Chromatid!#!Paired?!
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Metaphase!II! Metaphase!Chromosome!#!Chromatid!#!Paired?!
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Anaphase!II! Anaphase!Chromosome!#!Chromatid!#!Paired?!
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Chromosome!#!Chromatid!#!Paired?!
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Telophase!II! Telophase!Chromosome!#!Chromatid!#!Paired?!
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Chromosome!#!Chromatid!#!Paired?!!
!!!!
Cytokinesis! Cytokinesis!Chromosome!#!Chromatid!#!Paired?!
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Chromosome!#!Chromatid!#!Paired?!
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!!
6.1 Meiosis ! Meiosis is an important aspect of sexual reproduction. ! Sexual reproduction, through
the shuffling of DNA, produces genetic diversity.
! This variation offspring produces individuals that may have advantages over one another.
Terminologies ! Gametes = egg cell or sperm cell ! Fertilization = process in which gametes
are combined to form a zygote ! Zygote = combination of egg and sperm
cell ! Embryo = cells that are formed after
zygote undergoes mitosis
�Meiosis��is derived from the Greek word meion, which means to reduce. ! The process of meiosis results in the production
of special cells called gametes. ! Cell division occurs over two stages in meiosis:
once at the end of meiosis I and again in meiosis II.
! The process of meiosis shuffles genetic information and results in variation in genes.
Role of Gametes
! Normal body cells have a diploid chromosome number, meaning chromosomes occur in pairs. ! One from father and one from mother
! In humans, the male and female each contribute 23 chromosomes, total of 46.
! When fertilization takes place: 23 (egg) + 23 (sperm) = 46 (zygote)
g2 ( paired )
Role of Gametes
! The zygote goes on to develop into an embryo, and on into a complete individual.
! When the time comes, the cycle repeats.
Role of Gametes ! Humans produce gametes (either egg
or sperm) that have half (haploid) the normal number of chromosomes.
