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.
·meiosis ensures that the gametes formed are haploid from 2n to n
.ref to reduction division occurring in meiosis 2
.zygote becomes diploid due to the 2 sets of chromosomes from sperm and ovum
.can survive without the reproductive system
.reasons can be due to infection such as cancer of prostate in men or removal of uterus
.discuss the social implications that occur with the procedure that is in contrast with religion
<span>Synaptic cleft or the terminal buttons that transmits neurotransmitters to the next neuron, received by its dendrites and is relayed now throughout the system until it reaches the brain.
The messages must travel the distance of the nerves to the brain which are processed and made decisions, from the distance of the nerves from the sense organs, then travel back to the muscles that need to respond through the nerves.<span> </span></span>
The answer is cell. cell is the basic unit of humans
In the case of newborn twins, Brianna blood pressure is not normal but rather is low at 85/55 compared to Christophers 110/70. She has inadequate pumping of blood from her heart to the body while her breathing is rapid and deep in trying to get oxygen. It is because of inadequate pumping of blood that may lead to issues with her lungs.
Before she was diagnosed with retractile sclerosing mesenteritis, her eyes and lips were blue while her blood pressure could not read. After two weeks o her surgery, her blood pressure dropped severely low and had a breathing tube and 13 IV lines. She had caused lung damage caused by aspirations of contents in the stomach.
By third week she was in a coma but regained her physical skills and her consciousness after her last surgery (fourth).
