1. Genetics Notes

2. How does this happen?

3. Heredity
The passage of genetic instructions from one generation to the next generation
Traits are passed from parents to offspring through genetic material

4. Genetic Material: In the Nucleus
DNA
Genes
Chromosomes
Genetic material is located in the nucleus of each cell!!!

5. DNA Deoxyribonucleic Acid
DNA has a double helix shape (twisted ladder)
DNA is divided into segments called genes

6. Genes and Chromosomes
Gene: A segment of DNA that codes for a specific trait
Each of your cells has 46 strands of DNA inside (in the nucleus)
Each DNA strand is wound up tightly around itself and is called a chromosome
Replicated Chromosome

7. Karyotype: picture of all of the chromosomes in the nucleus of a cell

8. DNA, Genes, and Chromosomes

9. Traits
Inherited traits: physical characteristics that are passed on from parent to child through DNA
An organism can only pass its DNA to its children...nothing else!
This means that an organism can only pass on traits that they are born with!
Examples: eye color, height, gender, ear lobe shape, skin color, baldness, etc.

10. Traits
Acquired traits: changes to physical characteristics that occur after conception/birth due to the environment
Examples: broken bones, tattoos, haircuts, weight, bacterial/viral diseases, good grades, athletic achievements, etc.
Acquired characteristics CANNOT be passed on from parents to offspring!

11. Environmental Influence
Inherited traits are sometimes influenced or changed by the environment (these changes are NOT inherited/passed on)
Example: height is affected by diet
Example: muscle strength is affect by exercise

12. Inherited Traits and Genetic Material
Inherited traits are governed in the genetic material found in genes, within chromosomes in the nucleus