Reproduction and Genetics CHapter 6+7

Inside the Cell Chromosomes - tightly wound DNA

Mitosis and Meiosis Mitosis - creates identical copies, can be used for growth, repair, and reproduction Meiosis - creates sperm and egg (1/2 the number of chromosomes), only used for reproduction

Types of reproduction Sexual Reproduction - union of gametes through meiosis (sperm and egg meet) - half the number of chromosomes are found in each gamete - creates four new cells Asexual Reproduction - identical copies of cell through mitosis - identical number of chromosomes in both parent and offspring - creates two new cells

Sexual Reproduction Meiosis - makes sperm and egg (each have 1/2 the number of chromosomes) Fertilization - sperm and egg meet (together they provide the full set of chromosomes) Differentiation - the cell rapidly grows due to mitosis

Which has more variation? SEXUAL REPRODUCTION! Random assortment of genes from mom and dad

Plant Reproduction Occurs in the flower: Pistil - female reproductive organs Stamen - male reproductive organs

Seed

cancer Rapid Mitotic division

punnet Squares Dominant - trait shows up most frequently Recessive - trait shows up less frequently Phenotype - the trait that shows Genotype - the gene that shows

genetic Engineering Manipulating genes to create modified organisms Cloning - taking the DNA from one organism and placing it into the egg cell of a different organism to create an identical organism.

Evolution Gradual change in an organism over time Adaptation - traits allow you to survive in your environment Extinction - this occurs when you cannot survive in your environment