It would slow down in the stage of growing or
Answer:
D
Explanation:
Nutrition wise euglena is a producer, but locomotion wise it is classified as animal. Other example is chlamydomonas
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.
Presence of a teratogen in the body of mother during pregnancy is responsible for mal growth of child or incomplete growth which may lead to abortion, still birth or even a defective child.
<h3><u>Explanation:</u></h3>
A teratogen is a substance that is known to cause <em>defects</em> in growth of child during the intrauterine growth period. Thalidomide was used as a morning sickness drug which relieved the vomiting nature of the would be mother. But the presence of thalidomide was responsible for less growth of limbs of the child. Alcohol in intrauterine life may cause Fetal Alcoholic Syndrome which damages the fetus' sense organs and neural cord.
The presence of a teratogen during the 1st trimester is more serious than in last trimester because the main formation of different organs and systems take place in the 1st trimester and maturity takes place in third trimester.