In gymnosperm reproduction, which of these takes the place of water in the transfer of sperm to eggs?
a)haploid cells
b)male cones
c)small gametophytes
d)pollen tubes

What do nitrifying bacteria convert

Milk production during breastfeeding is increased by the suckling of a newborn from his mother's nipple. this type of feedback mechanism best describes a positive or negative

Identify the structures ! 20 points