Title your page: Sexual vs. Asexual Reproduction Notes Purpose of Reproduction • To make sure a species can continue. • Reproduction - the process by which an organism produces others of its same kind. Use the whole rest of the page to draw this chart. Write in margin Sexual Reproduction Asexual Reproduction A= Not Number of Parents Picture with explanation Offspring looks like… Genetic Diversity? Time to reproduce Examples You will then use the following slides to fill in notes on each section in the chart. Write small so that all the information will fit. Sexual Reproduction (write in chart) • Requires 2 parents: two sex cells (egg and sperm) that require fertilization Egg Picture Offspring Sperm The egg and sperm join to form an entirely new organism with traits of both parents • Offspring look genetically different from the parent organism due to mixing of DNA • The advantage is that genetic diversity allows a variation in traits and enables a species to be more able to adapt to environmental changes Time required to sexually reproduce Reproduces slowly (ranges from a few to many months) since the organism’s DNA is more complex that an organism that uses Asexual reproduction Examples of Sexual Reproduction • Mammals such as humans, gorillas, elephants, rats, zebras, and dolphins • Flowers that contain a pistil (female part) and stamen (male part) also There MUST be a male and female parent for an organism to sexually reproduce. Draw this picture and label the pistil and stamen Read the following slide. Then on the next page in your notes (after your chart), write the title and summarize the difference between internal and external fertilization. Sexual Reproduction: Internal vs. External Fertilization Internal Fertilization • • Fertilization occurs within the female. Internal fertilization occurs in mammals, insects, birds, reptiles. – Mammals (gorillas, lions, elephants, rats, zebras, and dolphins have live births) – Insects, birds, reptiles lay eggs • • External Fertilization External fertilization usually requires a medium such as water, which the sperms can use to swim towards the egg cell. External fertilization usually occur in fish and amphibians. The females lay the eggs in the water and the male squirts the sperm in the same area. Asexual Reproduction (write in chart) • A new organism (sometimes more than one) is produced from one organism. Offspring Offspring Offspring Parent One parent produces uniform offspring that are Offspring an exact copy as the parent (same DNA). • The offspring will have hereditary material uniform with the hereditary material of the parent organism. This means they will be genetically identical. • Asexually reproduced organisms cannot develop much variety (no genetic diversity), because they are “copying” the original organism exactly. • Asexual Reproduction happens quickly causing rapid population growth Types of Asexual Reproduction • • • • • • Budding Vegetative Reproduction Fragmentation Regeneration Spores Fission (Binary fission) Only write the types in the box on your chart. On the next page in your notes, you will describe each type in detail. Sexual vs. Asexual Reproduction Notes continued Sexual Reproduction: Internal vs. External Fertilization (your summary should be written here) Types of Asexual Reproduction Type of Asexual Reproduction Budding Definition Picture with examples Budding • Process by which a new, duplicate plant or animal begins to form at the side of the parent and enlarges until an individual is created. • Very common in plants. Hydra offspring Yeast Cactus Vegetative Reproduction • Form of asexual reproduction in plants where parts of the plant fall off and develop into new plants without seeds or spores. • Examples: potato tubers, tulips, strawberry, blackberry Fragmentation • When a plant is broken in 2 or more pieces, and each one grows into a new individual. • Lichens, Airplane Plant Amoeba Lichen Airplane Plant Regeneration • The ability to restore lost or damaged tissues, organs or limbs. • It is a common feature in invertebrates, like starfish. Spores • Uni-cellular bodies formed by the parent organism to carry out reproduction. If environmental conditions are suitable, the spore will develop into an individual. • Most common in fungi. Fission (Binary Fission) • A type of cell division in which one cell divides into identical cells. • Examples: Paramecium, Amoeba, Euglena IMPORTANT! • Asexual reproduction results in offspring that are genetically identical to the parent organism. • Sexual reproduction results in offspring that are genetically different from the parent organisms.