Summary Life Sciences P1: Reproduction in Vertebrates

PAPER 1

REPRODUCTION IN VERTEBRATES

TYPES OF FERTILIZATION

External Internal
Occurs outside of the female’s body, in the Occurs inside the female’s body
water

TYPE OF REPRODUCTIVE STRATEGY

1 Ovipary
- Eggs are laid and hatch aftertime
- A shell protects the embryo
- Yolk nourishes the embryo

2 Ovovivipary
- An embryo develops inside an egg
- The egg develops inside the body
- The young hatch inside the mother’s body
- The young are born alive

3 Vivipary
- Egg is fertilized internally.
- An embryo develops inside an egg
- Young are born alive

PARENTAL CARE
- Prenatal energy (before birth) or postnatal energy (after birth) that is supplied by the
parents to ensure survival of the offspring
1 None
- Many eggs are laid
- Prenatal energy is given before birth
- Low survival rate

2 Lots
- Few eggs are laid
- Postnatal energy is given after birth
- High survival rate