The competitive effect of one species on another (interspecific competition) is related to…
a. how strongly each competitor can obtain and retain the limiting resource
b. the population density of the competitors
c. the degree of niche overlap
d. all of the above
e. none of the above

d)All of the above

Explanation: Competitive effect is defined as the interaction created between species or organism , which usually results in negative situation. There are certain condition for the competition such as  supply of any resource in limited quantity, etc.So competition is also invoked by the density of the species present and in order to exist  in an ecosystem and thus there is the high chances of the overlapping of species as well.

Therefore,option(d) is the correct option.

fertilization, pictured in figure 24.23a is the process in which gametes (an egg and sperm) fuse to form a zygote. the egg and sperm each contain one set of chromosomes. to ensure that the offspring has only one complete diploid set of chromosomes, only one sperm must fuse with one egg. in mammals, the egg is protected by a layer of extracellular matrix consisting mainly of glycoproteins called the zona pellucida. when a sperm binds to the zona pellucida, a series of biochemical events, called the acrosomal reactions, take place. in placental mammals, the acrosome contains digestive enzymes that initiate the degradation of the glycoprotein matrix protecting the egg and allowing the sperm plasma membrane to fuse with the egg plasma membrane, as illustrated in figure 24.23b. the fusion of these two membranes creates an opening through which the sperm nucleus is transferred into the ovum. the nuclear membranes of the egg and sperm break down and the two haploid genomes condense to form a diploid genome.

explanation: