Reproduction

Asexual Reproduction

does not involve the production of gametes (common in invertebrates)

Sexual Reproduction

Involves the production of haploid gametes by meiosis (common in vertebrates, and many invertebrates use this in addition to asexual reproduction

Budding

One individual is produced by another

Fission

Creature divides in half

Fragmentation

Creatures break up into parts

Parthenogenesis

Female produces unfertilized diploid eggs. Some organisms can switch between parthenogenesis and sexual reproduction. Occurs in some invertebrates, arthropods, lizards, snakes, and fish

Dioecious

Male and female sex organs are found on separate individuals

Monoecious (hermaphroditic)

Male and female sex organs are found on the same individual. Most creatures will mate with another individual but some self fertilize

What species have temperature dependent sex determination?

Turtles and crocodilians Sequential hermaphrodites

Oviparity

Eggs are laid and may or may not be incubated Ex. most bony fish, some amphibians, most reptiles, all birds, some mammals

Ovoviparity

Fertilized egg develops inside the mothers body but is nourished by the yolk, live births. Ex. some cartilaginous fish, reptiles and bony fish

Viviparity

Fertilized egg develops inside the mothers body and get all their nutrition from the mother through the placenta. Ex. Most cartilaginous fish, some amphibians and reptiles, most mammals

What are the three extraembryonic membranes in embryonic eggs?

amnion, chorion, and allantois

How do all mammals feed their young?

with milk

Monotremes

Lay eggs and incubate them, the mammary glands lack nipples and the ducts open onto the skin, where it is then licked off of. Ex. duck pilled platypus and echidna

Marsupials

Babies are born underdeveloped after a short gestation, they make their way into the pouch and attach to the teat and finish their development. Ex. Kangaroos, wombats, opossums)

Placentals

Nourish unborn young through a placenta which is formed from an extraembryonic membrane and the lining of the uterus. The length of gestation varies based on the size of the animals and whether the baby is altricial or precocial