Answer:
The correct answer is b. must be present in a population before natural selection can act upon the population
Explanation:
Genetic variation can be caused by mutation, recombination between chromosomes during meiosis and by fusion of two genetically different gametes during sexual reproduction.
This genetic variation is necessary for the evolution of any population. Natural selection acts on every individual and it decreases the frequency of those alleles that are not suited for the environment and increase the frequency of those alleles which helps the individual to survive in the changing environment.
Therefore genetic variation must be present in the population before natural selection act on the.
Prokaryotes don't have a nucleus so it's bacteria :)
Chemical properties? raft? 2 different realms my friend
Answer;
A person who sprints for 45 seconds obtains most of his or her energy from muscle glycogen.
Explanation;
Muscle glycogen is the glycogen that is stored in the muscles and liver.
Glycogen is the primary source of energy during exercise, and low glycogen levels decreases the ability to gain strength and muscle. An athlete who sprints for 45 seconds obtains most of his or her energy from the muscle glycogen.
Answer: down
Explanation: bio teacher here
