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Flashcards in fertilization Deck (13):
0

external fertilization

outside body
in water
many egg many sperm, lack of protection
ex. fish and amphibians

1

internal fertilization

inside body
mostly on land
fewer eggs
still many sperm
ex land animals, Sharks, lobsters

2

parthenogenesis

development of an unfertilized egg into and adult
ex some insects

3

external development in water

fish and amphibians, yolk in egg source of food, O2 diffuses in from water, waste diffuse out, little of no parental care, survival rate is low

4

external development on land

yolk is a source of food, better survival rate, fewer eggs, birds and reptiles

5

internal development

involves growth of embryo within the body of the parent, high survival rate

6

internal placenta

umbilical cord: connects fetus to placenta
placenta: organ rich in blood vessels of mother and embryo, attached to the wall of the uterus, allows movement of nutrients oxygen and carbon dioxide by diffusion and active transport

7

internal non placenta

marsupials: pouched mammals
internal development without placenta attachment , embryo gets food from yolk in egg, born before development is complete, completes development in pouch on outside, mammary glands are source of nutrients in pouch
ex kangaroos

8

fish

external fertilization, external development, lots of eggs, no parental care

9

amphibians

external fertilization, external development, lots of eggs, no parental care

10

reptiles

internal fertilization, external development, many eggs, some parental care

11

birds

internal fertilization, external development, few eggs, much parental care

12

mammals

internal fertilization, internal development, few eggs, most parental care