1. Genetics and Heredity

2. Genetics and traits Genetics: the study of how certain features are passed from parents to their offspring Trait: a distinguishing quality that all members of a species have in common (eyes, chin, etc.) Variations: Different forms of the same trait (blue/brown/or green eyes, cleft chin)

3. Traits Heredity: the passing of traits from parents to offspring. Heredity plus your environment will work together to influence who you will become – “Nature Vs. Nurture Which do you think bear a greater impact on your development?

4. Reproduction and Heredity Four basic methods of asexual reproduction: – 1.Rooting: a cutting is taken from a mature plant and rooted to create a new plant (often used to get desirable traits in agriculture) – 2.Spores: like seeds can grow into new organisms – 3.Budding: small bud forms on the parent and breaks off to form a new organism’ – 4.Fission: (most common) dna is copied, cell divides, new cell membrane encases new daughter cells

5. Sexual Reproduction Requires male and female cells (sperm and egg) called gametes. Does asexual or sexual reproduction generate greater variety? Sexual reproduction creates greater variety due to a greater variety of trait possibilities. Traits are passed from parent to offspring in the form of genes Genes: small segment of DNA that carries hereditary info.

6. Genes Genes have all info needed to build, maintain, and reproduce an organism. Genes link together to form chromosomes Organisms’ cells can read the codes in chromosomes just like we read a book

7. Genetic Code

8. Genetic Code/Traits Some genes determine on trait: – Straight hairline or widow’s peak – Earlobes are attached or free

9. Heredity Recessive trait Dominant trait This woman’s genotype homozygousheterozygous

10. DNA http://www.youtube.com/watch?v=8kK2zwjR V0M http://www.youtube.com/watch?v=8kK2zwjR V0M

12. DNA is a molecule shaped like a twisted ladder called a double helix Sugar and phosphate make the support/legs of the ladder Nitrogen bases such as adenine (A), thymine (T), guanine (G), and cytosine (C) are paired together to make the “rungs” of the ladder

13. Nucleotide: the “rungs,” or the combination of bases Certain nitrogen bases always pair up: – A-> T – C->G

14. Replication: The DNA strand unwinds, unzips, new nucleotides pair up with existing, exposed nitrogen bases and new sugar/phosphate support is produced.

16. Mutations Mutations are “errors” in genetic code Seedless grapes are an example. Mutation: a change in the sequence of one or more nucleotides in a DNA molecule

17. Substitution:Sickle Cell Anemia Insertion:Huntington’s disease Deletion:Cystic Fibrosis Inversion:Hemophilia

18. Mutations Cont Some mutations do not effects the organism Some affect appearance and health, some only one of these Some mutations are caused by a mistake in DNA replication and take years to develop. Some are uncontrollable, others are not Mutagen is a physical or chemical agent that causes mutations to occur Radiation, smoke, chemicals, pesticides, drugs, x- rays, ultraviolet light, radiation.

20. Chernobyl http://www.youtube.com/watch?v=IEmms6vn -p8 http://www.youtube.com/watch?v=IEmms6vn -p8