1. 7B- Genes, Chromosomes, and Heredity

2. 1. Chromosomes Found in the nucleus
Number of chromosomes in each cell varies by organism
Occur in pairs

3. 2. Human Chromosomes All human cells contain 46 chromosomes (23 pairs)
Each member of the pair of chromosomes contains the same type of genes (ex: eye color)

5. 3. Sexual Reproduction
Egg and sperm each contribute one member of each pair of chromosomes
The zygote that is formed has 23 pairs, (46)chromsomes
One of each type of gene comes from each parent

6. 4. Punnett Squares

7. 5. Incomplete Dominance
Two traits combine or blend together to produce a different trait
No dominant trait and no recessive trait
Both traits have about the same influence
Examples: chickens and flowers

8. 5. Incomplete Dominance

9. 6. Multiple Gene Inheritance
More than two genes are responsible for producing a single trait
Example: height, hair color

10. 7. Determining Gender 23rd set of chromosomes determines gender
Females only have X chromosomes
Males have X and Y chromosomes
X = female; Y=male
Father determines the gender of child

11. 7. Determining Gender

12. 8. Sex Linked Traits
Inherited traits that have genes on the 23rd chromosomes
Carrier – someone who carries a gene but does not express it themselves
Example: red-green colorblindness

13. Can you find the hidden symbols?

14. What do you see in the circle?

15. Can you see what is hidden?

16. 9. Inherited Disorders
Abnormal traits that are passed on through genes
We know that all things work together for the good of those who love God: those who are called according to his purpose. (Romans 8:28)