Internal and External Fertilization

Compare:

Basic:
•both need egg and sperm together
•both create offspring

Contrast:

Basic:
•internal- egg and sperm are required to find each other inside of bodies
•external- egg and sperm are required to find each other outside of the female's body
•internal- child is formed inside mother's body
•external- child is formed outside mother's body

Animals:
•internal- most land animals, both vertebrate and invertebrate
•external- almost all aquatic animals, most fish, and many amphibians

Internal Fertilization:
internal fertilization is where the egg and sperm are combined within the female and the child remains inside of the mother until birth

External Fertilization:
external fertilization is where the egg and sperm are required to find each other outside of their bodies and the child is contained in eggs underwater

Advantages:
increases chance gametes meet
higher chance of survival
Disadvantages:
limited amount of offspring
higher risk of std's

Advantages:
more offspring
more genetic variation
Disadvantages:
wasted gametes
less chance of contact between sperm and eggs