(a)(i) Placentation: This is the arrangement of ovules, within the ovary.
(b) (i) Organs Associated with human
placenta: Umbilical cord, Uterus
(b)(ii) Functions of Placenta:

Establishes connection between the embryo and the mother.
Carries oxygen/water/food/ nutrients from mother's blood to foetus.
Removes waste/urea/salt/carbon dioxide from foetus blood to mother's blood for elimination.
Produces progesterone/hormone for maintenance of uterine wall/ endometrium/pregnancy.
Carries antibodies from mother's blood to foetus.

(c) Viviparity: This is a type of reproduction in which the young develops inside the mother's body. Obtaining nutrients directly from the parent. When fully developed, the young are born alive.
(ii) Territoriality: In many animal species individuals, usually males mark out areas/territories where they can live and breed.

They guard these territories fiercely.
Chasing away other members of the species.
Only vigorous individuals are able to establish large territories, secure suitable mates and produce many offspring.
Territoriality limits overcrowding.
Animals that carry out this phenomenon are lizards, lions, etc.

(iii) Seasonal migration:

In many habitats food supply is affected by seasonal changes. Food is abundant in rainy seasons but scarce in dry seasons.
Animals overcome these seasonal food shortages by moving to other habitats during unfavourable seasons.
Such large scale seasonal movements of animals between habitats are called migrations.
Other causes of migrations are temperature changes and breeding seasons.