Asexual vs. Sexual One parent Two Parents Genetically Identical Genetic Variation

Mitosis Reminder Cell division  genetically identical cells ***Asexual Reproducing Organisms use mItosis!!

EQUAL division of the cytoplasm EX: Paramecium, Amoeba Video Clip

Cytoplasm divides unequally but still same DNA Ex:Hydra, yeast budding yeast time-lapse

Regeneration New organism from part of one Restoration of lost body parts Ex: Star fish, planaria planaria in ?

Spore – grow into identical organism –Ex: Mold, Mushrooms –SPORULATION SONGSPORULATION SONG

Asexual Plant Reproduction Growing identical plants from original Quick Video

Vegetative Propagation: Cuttings grafting Pieces of stems, roots, or leaves are used Ex. Roses, sugar cane, bananas, apples

Vegetative Propagation: Runners Stems grow on the surface New plants grow from stem Ex. strawberries

Vegetative Propagation: Tubers Underground stem for food storage Ex. Potatoes, yams

Vegetative Propagation: Bulbs Underground stems for food storage Each bulb becomes new plant

Vegetative Propagation: Rhizomes Stems grow underground New plants produced on nodes Ex. Lawn grasses, ferns, irises

Made possible by: Sex Cells ONLY (gametes) –Sperm and Egg –½ # chromosomes ****Gives genetic VARIATION Used to make ME and You!!!

Gametogenesis (meiosis) Definition – using of meiosis to make gametes (Gamete – Sex Cell Genesis – To make) Oogenesis Oogenesis Makes 1 Functional Egg Makes 1 Functional Egg and 3 Polar Bodies and 3 Polar Bodies (which are unused and discarded) Spermatogenesis Spermatogenesis Makes 4 functional sperm Makes 4 functional sperm

The basics - 2 divisions No interphase 2!!! IPPMMAATTIPPMMAATT

Exchanging of genes during Metaphase 1 LEADS TO MORE VARIATION DRAW IT from next page!!! CROSSING-OVER

Crossing-Over Crossing-over multiplies the already huge number of different gamete types produced by independent assortment 

Independent Assortment – Genes are inherited randomly Genes are inherited randomly A gamete may get some chromosomes from the mother and some from the father A gamete may get some chromosomes from the mother and some from the father Leads to More Variation Leads to More Variation In humans over 8,000,000 different In humans over 8,000,000 different chromosome arrangements!!! Red Brown Blue Red Black Blue Red Brown Green Red Black Green Yellow Brown Blue Yellow Black Blue Yellow Brown Green Yellow Black Green

Some Problems that can occur during Meiosis – Genetic Disorder passed to Offspring (Nondisjunction  ) Genetic Disorder passed to Offspring (Nondisjunction  ) Chromosomes do not separate properly Chromosomes do not separate properly Zygotes end up with more or less chromosomes than they are supposed to Zygotes end up with more or less chromosomes than they are supposed to Example: Down Syndrome – extra 21 st chromosome Example: Down Syndrome – extra 21 st chromosome

Karyotype: - Picture of chromosomes -Way to look for genetic diseases Sex determination: -XX - Female -XY - Male

Boy or Girl? The Y Chromosome “Decides” X chromosome Y chromosome

External Fertilization – Needs water for sperm to swim Internal Fertilization – usually on land (moist inside for sperm to swim) External Development – (Eggs) –Water – many, no protection, nutrients given by yolk –Land – less, more protection, nutrients given by yolk Internal Development – Inside mother –Advantage – protection during development, care after birth –Disadvantage – less offspring, harmful to mother while pregnant

External Fertilization – Water needed for sperm to swim External Development – In the water Lay MANY eggs No parental care Naming Eggs 1:16Naming Eggs Video Clip in HD FISH and AMPHIBIANS Fill in the chart while we go over the next bunch of slides

Internal Fertilization – On DRY land!! External Development – True Egg turtle laying eggs turtle laying eggs Reptiles – Medium amount of eggs Reptile - Parental Care?

Internal or External Fertilization? Internal or External Development? Many Eggs or Few Eggs? Little Parental Care or A lot of Parental Care? Feeding clip

On land – True EGG A – Allantois B – Amnionic Sac C – Chorion D – Shell E – Embryo F – Yolk G - Albumin G

A – Allantois – Wastes stored here B – Amnionic Sac – Protects, cushions C – Chorion – Membrane surrounds all structures D – Shell – Protects, exchange of gases occurs here E – Embryo – developing animal F – Yolk – Provides nutrients G – Albumin – Egg Whites (protein)

All have INTERNAL FERTILIZATION most have internal development # Eggs (offspring) – Few Parental Care – YES!!!! Mammal Mother Clip Birth Clip

Non- placental Give birth to immature babies that develop in pouch Examples: Kangaroo Opossum Koala Tasmanian Devil BIRTH

Mammals that LAY EGGS!!! Examples: Duck-billed platypus Echidnas Birth

Involves 2 parents Each gives ½ information This is possible because of MEIOSIS Leads to RECOMBINATION AND VARIATION