1. Human Chromosome and Karyotyping
Biology 12

2. Human Chromosomes: Humans have 23 pairs of chromosomes
22 pairs are called autosomes (they are the same in males and females

3. Sex Chromosomes: One pair of chromosomes differ in males and females,
Called sex chromosomes, there are two types:
X chromosome
(similar to all other
chromosomes)
Y chromosome
(shorter and hook
shape)

4. Females:
Have two x chromosomes (one from mother and one from father)

5. Males:
Have one x chromosomes (from mother) and one y (from father)

6. Karyotyping:
A karyotype is an organized profile of a person's chromosomes.
Chromosomes are arranged and numbered by size, from largest to smallest. This helps scientists quickly identify chromosomal alterations that may result in a genetic disorder.
To make a karyotype, scientists isolate DNA and then take a picture of the chromosomes. Then they cut them out and match them up using size, banding pattern and centromere position as guides.

7. Karyotyping: the process

8. Joke of the day:

9. To do:
Worksheet: Chromosomes and Genes
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