Reproduction! Purpose: Create offspring for the continuation of your species

Asexual (clones) Only 1 parent needed made by prokaryotes, protists! Binary fission & Mitosis: photocopy all DNA & rip cell in half Circular DNA in prokaryotes Bacteria dividing by fission. Ameoba dividing by fission.

3 different examples of budding Yeast Hydra The most common mode of vegetative growth in yeast is asexual reproduction by budding.[30] Here, a small bud (also known as a bleb), or daughter cell, is formed on the parent cell. The nucleus of the parent cell splits into a daughter nucleus and migrates into the daughter cell. The bud continues to grow until it separates from the parent cell, forming a new cell.[31] The daughter cell produced during the budding process is generally smaller than the mother cell. Some yeasts, includingSchizosaccharomyces pombe, reproduce by fission instead of budding,[30] thereby creating two identically sized daughter cells. Organisms such as hydra use regenerative cells for reproduction in the process of budding. In hydra, a bud develops as an outgrowth due to repeated cell division at one specific site. These buds develop into tiny individuals and when fully mature, detach from the parent body and become new independent individuals Spider Plants

Sex: why bother?!?! Plants, animals, fungi… Cell still duplicates DNA first But, meiosis rips the cell apart TWICE creates gametes (eggs & sperm) with genetic variety crossing over and independent assortment Diploid (2n) cell  Haploid (n) cells

Locations of meiosis in tulip and lily (hermaphrodite flowers) Anthers produce pollen (sperm) Pd 4 did a lot of plant reproduction Monday since lab is not until Wednesday. Ovaries make eggs at flower base

Seed to fruit… the next generation! Seed’s energy comes from stored starches It knows which way to grow = TROPISMS Photosynthesis picks up once above ground

Figure 46.8 Reproductive anatomy of the human male It takes 64 days from start to finish for a single sperm cell to develop. The testes create millions of sperm every day, so there are always sperm at different developmental stages in the testes, ensuring a constant production. After the sperm are created they take up to a couple of weeks to a month to move through the ducts and epididymis before ejaculation. Testes produce hormones and create sperm

Human Spermatogenesis Starts at puberty (~11-15) Testes produce sperm and testosterone, (hormone responsible for male characteristics) Millions made daily! Quantity over quality ALL 4 HAPLOID GAMETES SURVIVE

2) Fertilization occurs (= zygote) 3) Implantation; placenta attaches here 1) Releases egg & hormones Egg release in human female image.

Human Oogenesis Primary eggs made while in womb! 4 Hormones prepare for fertilization  Ovaries make hormones develop nutrient-rich uterus lining Ovulation releases mature egg If no fertilization, lining dissolves (menstruation/”period”) Can get pregnant 5 days around ovulation! Sperm live 5 days inside womans body Eggs only viable for 1 day

Fertilization = merging of 2 complete sets of DNA What organelle will sperm require a ton of since they have to swim a lot? http://science.howstuffworks.com/life/human-biology/human-reproduction10.htm

Ovary  Fallopian Tube  Uterus

Figure 46.18 Mommas belly growing Cool Sonogram Fetal movie 4 min baby moving kicking in belly

Embryo  Fetus Time lapse birth to 12 years – cool! http://www.youtube.com/watch?v=RtyqS68ViWk&safety_mode=true&persist_safety_mode=1&safe=active “The embryo is defined as the developing pregnancy from the time of fertilization until the end of the eighth week of gestation, when it becomes known as a fetus,” says James A. O’Brien, MD, ob-gyn, medical director of inpatient obstetrics at Women & Infants Hospital of Rhode Island. During the embryonic period, cells begin to take on different functions. The brain, heart, lungs, internal organs, and arms and legs begin to form. Once baby is a fetus, it’s more about growth and development to prep for life on the outside

Identical Twins (monozygotic)

Fraternal twins (dizygotic) 2 eggs released at same time Both fertilized with sperm Not identical babies!

Conjoined Twins

Pregnancy Woman ovulates  sex (~6 day window!) Fertilization: sperm(n) & egg(n) DNA unite Diploid zygote divides  2  4  8 cells, etc Ball of stem cells implants itself into uterine lining Embryo: Heart beats, brain forms Fetus obtains nutrients through placenta & umbilical cord (11 weeks  birth) Uterus contracts… baby is born… more contractions… placenta is released

Delivery is initiated by hormone spikes: a positive feedback loop

How do other organisms reproduce?

C. elegans roundworms Hermaphrodites (XX) and males (XO)

Gymnosperm reproduction Angiosperms, also called flowering plants, have seeds that are enclosed within an ovary (usually a fruit), while gymnosperms have no flowers or fruits, and have unenclosed or “naked” seeds on the surface of scales or leaves. Gymnosperm seeds are often configured as cones. The characteristics that differentiate angiosperms from gymnosperms include flowers, fruits, and endosperm in the seeds. Gymno = uncovered Angio = covered

Frog Reproduction At the breeding site, the male mounts the female and grips her tightly round the body. Typically, amplexus takes place in the water, the female releases her eggs and the male covers them with sperm; fertilization is external. In many species such as the Great Plains toad (Bufo cognatus), the male restrains the eggs with his back feet, holding them in place for about three minutes.[103] Members of the West African genus Nimbaphrynoides are unique among frogs in that they are viviparous; members of the Tanzanian genus Nectophrynoides are the only frogs known to be ovoviviparous. In both cases, fertilization is internal and females give birth to fully developed juvenile frogs.[106][107]