Genetics: Class Notes 2- Traits and Chromosomes

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Genetics Class Notes 2- Traits and Chromosomes
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I. Where do my traits come from?

1. From your parents
2. More specifically, from the chromosomes your
   parents gave you.

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II. Chromosomes in detail

• Chromosomes are made of _______.
• Each chromosome contains many genes.

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• C. Each chromosome has a partner (homologous
  chromosome) that contains the same type of genes.
  
• D. One chromosome is from your mother, and one is
  from your father.

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III. Chromosome quantities

• A.Organisms of the same species have the same
  number of chromosomes
• humans46 23 pairs
• goldfish94 47 pairs
• fruit flies8 4 pairs

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IV. What are the two types of cells?

1. Body cells have 2 sets of chromosomes diploid
   cells
2. Reproductive cells (sperm egg) have one set.
   These are called gametes haploid cells

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V. How are these cells formed?

1. New body cells are exactly the same as the
   original and are formed through a process called
   __________.
2. Gametes have HALF the chromosomes as the original
   and are formed through a process called meiosis.

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Summary

• What are the two processes that make new cells?
• What type of cell does each process make?