Kangaroos are mammals that lack a placenta. Therefore, they must have an alternate way of supplying the developing embryo with

yolk sac

explanation:

the placenta does not develop for a long time so the alternate way of supplying the developing embryo is through the yolk sac which the embryo can receive nutrients and respiratory gas exchange through which the placenta will be formed later.

succession returns a disturbed

ecosystem to a more stable state. this is also classified into two (2) types:

primary succession and secondary succession. the primary succession arises when

a new land is transformed and a bare rock has been exposed providing an environment

that can be occupied for the first time. while, secondary succession occurs

when a previously occupied environment was disturbed that kills much of all its

community

explanation: