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|[pic] |1.3.5 Practice: DNA and Heredity |
| |Practice Assignment |
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| |[pic] |
| |Biology Sem 2 (S2598061) |
| \ …show more content…

(1 point)

Prophase: the chromosomes darken and become more defined, the nucleic envelope breaks down

metaphase the Sister chromatids meet up in the MIDDLE. (m for middle and metaphase)

anaphase: the pairs move APART (a for apart and anaphase)

telophase: the new cells begin to develop

2. a) How does meiosis introduce genetic variation into offspring? Think about how the chromosomes line up.(1 point)

1 by crossing over in prophase I , 2 , by indpendenent assortment and three by mutations in S phase

b) How do the products of meiosis compare to the original cell? Think about chromosome number. (1 point)

Meiosis results in four daughter cells (gametes) which have half the number of chromosomes of the original cell. They are therefore called haploid cell

c) Why are there two sets of phases during meiosis, but only one during mitosis? Think about what is different about meiosis and mitosis. (1 point)

Mitosis is the cell cycle for somatic cells which are diploid (2n).

Meiosis is the cell cycle for germ cells (gametes) where they are haploid (n) so that is why they have two sets of phases.

3. a) A plant can have either tall (T) stems or short (t) stems. Two plants are crossed. One has the genotypeTt and the other has the genotype Tt. Fill in the Punnett square below for this cross. (1

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