How are enzymes used in a chemical reaction?

Elephants in the savanna regions of africa dig holes in dried up river beds to reach water lying just below the surface. these holes provide drinking water for other animals as well. so, without the elephants, many animals might otherwise die from lack of water during the dry season. the location in which the elephants live is an example of a/n and the role they play in creating water holes is an example of a a) ecosystem; habitat b) community; niche c) habitat; niche d) niche; habitat

Crossing over and independent assortment are important activities that occur during meiosis. what is the significance of these activities

What do we call the process when two dominant alleles are expressed and do not blend? a.incomplete dominance b.codominance c.multiple alleles