I'm alittle confused on how I'm supposed to answer this could you help me ?

a) Petiole

b) initiate growth of cells at the tips of the shoot and roots

Explanation:

Petiole is the plant structure that attaches leaf blade to plant stem. Meristem is present at the tip and sides of stems, roots and at inter nodes and helps in its growth.

Hope it helps! :)

a tetrad is the foursome during meiosis made by two homologous chromosomes that have each already replicated into a pair of sister chromatids.

i think that it is plants