Reproduction Notes

I.Reproduction A. – offspring arise from a parent and inherit all of the genes of that parent 1. Offspring have of the same chromosomes as the parent 2. Offspring are “clones” of the parent Asexual reproduction exact 100% single only

Asexual Reproduction 3. Most cellular organisms reproduce this way 4. Mitosis – duplication of all of its parts, two daughter cells formed uni simple

5. Types: a. – every organelle is copied and the organism divides into two equal halves - Bacteria and protist Binary fission

b. – new individual develops from an outgrowth of a parent, splits into two unequal halves and lives independently - Hydra and sponge Budding

c. – body part has broken off and the organism grows a new one - Starfish and flatworm Regeneration

d. – single parent breaks into parts that regenerate into whole new individuals - Planarians Fragmentation

e. – production of many spores in a spore case (spore – nucleus and cytoplasm within a hard case) - Molds, mushrooms and ferns Sporulation

f. – a new plant grows from a vegetative part - Bulb – short underground stem with stored food in leaves (onion and tulip) - Corm – short underground stem with stored food in stem (water chestnut and crocus) Vegetative reproduction

- Tuber – enlarged underground stem (potato and yam) - Runner – horizontal stem with buds along ground’s surface (strawberry and spider plant)

- Rhizome – underground horizontal stem (ginger and iris) - Cutting – cut a piece of plant (Philodendron)

- Grafting – stem or bud of one plant is joined permanently to another (rose and apple tree) - Layering – stem is bent over and covered with soil (raspberry)

B. – offspring arise from parents that share half of the genetic information 1. Offspring have of the chromosomes from each parent 2. Offspring the characteristics of each parent Sexual reproduction 50% 2 2 share

Sexual Reproduction 3. – cell division that reduces the chromosome number by half, 4 daughter cells formed Meiosis

4. Types: a. – egg is fertilized by the sperm inside the female - Mammals, birds, reptiles, insects and spiders Internal

b. – egg is fertilized by the sperm outside of the female - Female lays eggs and male fertilizes them -Fish, some amphibians and flowering plants External

Reproduction ProsCons Asexual Sexual Sexual vs. Asexual: Sexual vs. Asexual: Can you tell which one it is? Do not need to find a mate No genetic diversity (any harmful traits that the parent has will be passed on to offspring) Genetic diversity (less chance of getting harmful traits from parents) Need to find a mate