Oak Anthracnose. Anthracnose is a general term used to describe diseases that result in a wide range of symptoms including leaf spots, blotches or distortion, defoliation, shoot blight, twig cankers and dieback on many different deciduous trees and shrubs. In most cases, anthracnose does not cause permanent damage to established trees.
1 Germ cells have only half the number of chromosomes as a diploid cell Â­ one of each pair-and are termed haploid (n) . 2  In a human egg or sperm, there are 23 chromosomes, one of which is an X or Y. 3  The number of chromosomes is reduced from 46 to 23 during the process of meiosis.
In the case of humans, this means that parent cells have two chromosomes and gametes have one. During fertilization, gametes from the sperm combine with gametes from the egg to form a zygote. The zygote contains two sets of 23 chromosomes, for the required 46. All of the gametes in the motherâs eggs possess X chromosomes. The fatherâs sperm contains about half X and half Y chromosomes. The sperm are the variable factor in determining the sex of the baby.