biology form 4 chapter 5 meiosis
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Biology Form 4 Chapter 5 Meiosis PowerPointTRANSCRIPT
Necessity for Trait Inheritance in offspring for Continuation:
Specific characteristic that varies from one individual to another
• Because they are uniquely adapted to enable survival in the environment.
Transmission of traits from one generation to another generation by means of genetic codes
A cell with 2 sets of chromosomes is referred to as
diploid (2n). Somatic cells are diploid.
A cell with a single set of chromosomes is referred to
as haploid (n).
Gametes are haploid.
Necessity to maintain diploiddiploid chromosomal number and
production of haploidhaploid gametes in sexual reproduction
2n
Human somatic cell has46 chromosomes
23 pairs of homologous
chromosomes
nn
ovum
sperm
2n
Fertilisation
Zygote
Human gametes
Meiosis is the process of nuclear division that reduces the number of chromosomes
in new cells to half the number of chromosomes in the parent cell.
Meiosis produces reproductive cells
(gametes)
Sperm &
Ovum
Pollen grains & Egg cells
MEIOSIS I MEIOSIS II
• Prophase I
• Metaphase I
• Anaphase I
• Telophase I
• Prophase II
• Metaphase II
• Anaphase II
• Telophase II