Here We Go

AGENDA:
1) Take out stampsheet with UP 29-31
2) Review meiosis/Mendel
3) Face lab on UP 23-28

HOMEWORK:
1) Finish UP 23-28
2) Read section 11.2

Meiosis Review:
Gametes- Sex cells

• Males: Sperm
• Females: Eggs

Diploid (2N)- Two sets of chromosomes

Haploid (N)- One set of chromosomes

Zygote- A fertilized egg

Note- Gametes are haploid (N) and fertilization restores the diploid state (2N)

Meiosis is the process to make haploid gametes and the chromosome number is cut in half. This process takes place in the ovaries and testes and there are two cell divisions (look for photo below). Meiosis increases genetic variation which leads to the formation of many different gametes.

CELLS THAT UNDERGO MEISOS ALSO UNDERGO MITOSIS, NOT JUST MEIOSIS.

Genetics and Such:

Alleles: The letter which is either dominant or recessive

Heterozygous: Two different alleles

Homozygous: Two identical alleles

Genotype: The alleles (i.e., TT)

Phenotype: The outward, physical part (i.e., tall)

Punnett square can help determine the ratio of offsprings. You cross genotypes on the punnett squares.

The genotypes for this punnett square are Rr x Rr

The genotypes for the offspring would be 25% RR; 50% Rr; 25% rr

The next scribe is Josh