"Double fertilization involves two sperm cells; one fertilizes the egg cell to form the zygote, while the other fuses with the two polar nuclei that form the endosperm."
Muscle contraction that results in a change in joint angle is called <span>concentric contraction.
This contraction occurs when enough force that can overcome the resistance applied is developed by the muscle where this force developed is larger than the force of the resistance applied.</span>
Apparently it’s called the ovum
