Sexual Reproduction & Meiosis Why It’s Important They are the reasons why no one else is exactly like you

Sexual Reproduction 2 sex cells, sperm & egg, join to form a zygote, which will develop into a new organism with a unique identity A human egg & sperm at fertilization

Sex Cells Sperm- male sex cell (formed from meiosis) Egg- female sex cell (formed from meiosis)

Vocabulary Fertilization- joining of sperm & egg Forms a zygote Zygote- a diploid cell formed when sperm and egg join Diploid Cells- body cells; cells with pairs of chromosomes Skin, bone, brain cells, etc Haploid Cells- cells with HALF the number of chromosomes as body cells Sperm & Egg Haploid is Half of Diploid!

You Try It Q: How many chromosomes are in a human’s body cell? A: That’s Right! 46 Q: How many chromosomes would be in a human sex cell (haploid cell)? A: YES…23 Why?- Haploid cells have HALF the # of chromosomes as Diploid cells

How are sex cells formed? Meiosis- process by which the number of chromosomes is reduced by half to form sex cells Ensures offspring will have the same # of chromosomes as the parent

Fertilization

Fertilization Activity: Guess Who!!!! Kangaroo 16 Opposum 22 Snail 24 Corn 20 Cabbage 18

Slime: What is it???? Objective: Determine the state of matter of slime. How is your slime like a solid? How is your slime like a liquid? What state of matter were the slime ingredients?

Meiosis Review 1) If the haploid # of a white-tailed deer is 35. How many chromosomes would be in their sex cells? 2) A rabbit has a haploid number of 22. What is the number of chromosomes in the zygote of a rabbit? 3) The giant panda’s diplioid number is 42. What is its haploid number? 4) The hyena has 40 chromosomes in its body cells. How many chromosomes are in its sex cells?

Haploid v. Diploid 1. _______________: body cells, has double (or pairs) of chromosomes. 2. _________________: sex cells, had half the number of chromosomes in the body cells. 3. If dogs have 39 chromosomes in their sex cells, how many chromosomes are in their body cells? 4. If the diploid number of a koala’s body cell is 16, what would be the haploid number? 5. A fruit fly has 3 chromosomes in their sex cells. How many chromosomes would be present in the zygote? 6. The diploid number for a rabbit is 44. How many chromosomes are in their sex cells?  7. A spinach haploid cell contains 5 chromosomes. How many chromosomes are in spinach’s diploid cell?