1. Meiosis 1.After fertilization, 23 chromosomes from the female parent (egg) and 23 chromosomes from the male parent (sperm) join to make 46 chromosomes 2.Genes are found on chromosomes – one allele for each gene pair comes from each parent

2. How does all this happen? 1.Human body cells are diploid because they have 46 chromosomes 2.Human sex cells are haploid because they only have 23 chromosomes 1.Sex cells are formed during meiosis

3. 2.During meiosis, chromosome pairs separate and are distributed to two different cells. The resulting cells only have half the number of chromosomes from the original parent cell (haploid). Meiosis

4. 3.Similar to mitosis, meiosis results in four cells total.

5. 2.When sex cells combine (fertilization), mitosis begins and a new organism develops.

6. What is Selective Breeding? Organisms with desirable characteristics are mated Ex.) Your pet dog is an example of selective breeding Dogs are selectively bred for temperament and a variety of appearance traits (coat type, color, size). Some of this has to do with breeding dogs for certain jobs (hunters, herders, protectors etc) but a lot of it is just a matter of companionship. Cows have also been selectively bred. Angus cows are bred to increase muscle mass so that we can get more meat out of them, dairy cows are bred for increased milk production.

7. HUMAN INTERVENTION

8. SELECTIVE BREEDING The selection of certain seeds or animals for reproduction in order to influence the traits inherited by the next generation.

9. SELECTIVE BREEDING The Liger is the result of breeding a female Tiger to a male Lion. The liger has both stripes and spots. The stripes are inherited from its tiger parent and the spots from the lion parent. On their hind legs, ligers stand approximately 12 feet tall. At most, ligers may weigh up to 1,000 pounds.

10. The Cama is the result of breeding a Llama to a Camel. Parents in background of picture.

11. The Zebroid is the result of breeding a female Horse and a male Zebra. The Zedonk / Zonkey is the result of breeding a female Donkey and male Zebra.

12. Geep - These are the result of a sheep and a goat.

13. The Mule is the result of breeding a female horse (mare) to a male donkey (jack). The mule is superior to the horse in strength, endurance, intelligence and disease resistance.

14. Maroon & Red Bluebonnets

15. Polygenic inheritance (many genes, one trait) 1.A group of gene pairs acts together to produce a trait, which creates more variety in phenotypes. 2.Many human traits are controlled by Polygenic inheritance (many genes, one trait), such as hair, skin, and eye color. Polygenic traits: structure, body shape, hair, eye, and skin color

16. One Gene, Many Traits 1.Sometimes one gene influences more than one trait. Ex.) the white tiger’s white fur is caused by a single gene, but this gene influences more than just fur color. The gene that controls fur color also influences eye color.

17. Incomplete Dominance One trait is not completely dominated over another. These traits do not blend together, but each allele has its own degree of dominance.

18. Importance of the Environment Genes are NOT the ONLY influences on traits Ex.) 1. A guinea pig born with long hair, but its fur could be cut. 2.Your GENES make it possible that you will grow to be tall, but you need a healthy diet to reach your full potential height.

19. Recessive genetic disorders 1.When this occurs, both parents have a recessive allele responsible for this disorder and pass it to their child. 2.Because the parents are heterozygous, they don’t show symptoms 3.Cystic Fibrosis is a homozygous recessive disorder.

21. Recessive genetic disorders, cont. 4.Genes that determine the sex of an organism are XX in females and XY in males 5.Females produce eggs with X chromosomes only. Males produce sperm with either the X or Y chromosome.

22. Sex-linked disorders 1.An allele inherited on an X or Y chromosome is a sex-linked gene 2.Color blindness is a sex-linked disorder caused by a recessive allele on the X chromosome. 3.A Pedigree follows a trait through generations of a family

23. Color Blindness test: WITHOUT SPEAKING, please write down the numbers contained in the circles above and below.

24. ALBINOS Little or no pigmentation in the eyes, skin, and hair (or in some cases in the eyes alone). Inherited an altered copy of a gene that does not work correctly. The altered gene does not allow the body to make the usual amounts of a pigment called "melanin". True albinos have pink eyes and skin.

26. These are not albinos; they have pigmented eyes.

27. White Bengal Tiger

29. White Bluebonnets

30. Pink Bluebonnets

31. GENETIC ENGINEERING The selective, deliberate change of genes (genetic material) by man. The technique of removing, modifying or adding genes to a DNA molecule in order to change the information it contains.

32. Bright face of genetically modified corn plant: pest- infected non-GM (left) and pest-free GM plant (right) planted side-by-side in a field trial. (photo: Dr. Yu Jialin, China Agricultural University)

33. French genetic researchers created Alba for artist Eduardo Kac. Thanks to genes borrowed from a jellyfish, the albino rabbit glows green when placed under special lighting. In regular light, Alba appears like any other furry white rabbit. But place her under a black light, and her eyes, whiskers and fur glow a otherworldly green.

35. "Glow in the dark" fish. these genetically modified fish were developed by a Taiwanese aquatic firm, Taikong Group. They are planning to reproduce these fish in numbers and sell them for pets.

37. Scientists in the agriculture department of the Hebrew University in Rehovot have genetically engineered a chicken that has no feathers.

38. Weird Genetics No… I mean really, REALLY weird! Some of these disorders are mutations, others were selectively chosen by people. Enjoy the show!

44. DNA 1.X-ray photographed by Rosalind Franklin -1952 2.James Watson and Francis Crick identify structure – 1953 1.Appearance – twisted ladder/spiral staircase 2.Sides are made up of sugar (called deoxyribose) and phosphates

45. DNA 4.Each step is made up of a pair of molecules called nitrogen bases 1.4 kinds - Adenine, Thymine, Cytosine, Guanine 2.Adenine only pairs with Thymine; Cytosine only pairs with Guanine

46. DNA Replication 5.Replication begins when DNA separates and unwinds – like a zipper 1.Free-floating nitrogen bases pair with the bases of each half of the DNA molecule 2. 2 new DNA strands are formed

47. Mutations—genes that are altered or copied incorrectly 1.A mutation can be harmful, beneficial, or have no effect. 2.Chromosome disorders— caused by more or fewer than normal chromosomes. 3.(For Example:) Down Syndrome—caused by an extra copy of chromosome 21