- The environment needs to change in order to natural selection to occur.
Reason:
Because, Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the heritable traits characteristic of a population over generations.
2. Population has some genetic variations.
Reason:
Genetic variation is essential for natural selection because natural selection can only increase or decrease frequency of alleles that already exist in the population. Genetic variation is caused by:
mutation and random mating between organisms
3. Nature select organism with specific traits to survive and reproduce.
Reason:
According to Charles Darwin's theory of evolution by natural selection, organisms that possess heritable traits that enable them to better adapt to their environment compared with other members of their species will be more likely to survive, reproduce, and pass more of their genes on to the next generation.
Answer:
An arterie is a vessel that carries blood away from the heart, and a vein carries blood to the heart
Explanation:
Mark as barinly plzzz :))))
Answer:
In this case, it is likely that the polypeptide chain assumed an alpha helix configuration because the lipid bilayer did not have beta-barrel proteins.
Explanation:
A polypeptide chain is naturally polar, however, a lipid bilayer is naturally non-polar. This makes it difficult and even prevents the polypeptide chain from crossing a lipid bilayer, since the composition of these two elements does not allow them to mix. In that case, the polypeptide chain has two options to take to successfully cross the lipid bilayer.
The first option that the polypeptide chain has is to allow the creation of twisted beta sheets in the shape of a closed barrel in its structure. This only works if the lipid bilayer has beta barrel proteins in its composition to act as a transport channel for the polypeptide chain. However, few lipid layers have this protein.
Most likely, the polypeptide chain assumes an alpha helix conformation to cross lipid bilayers that do not have beta-barrel proteins. By assuming the beta conformation, the polypeptide chain reinforces the hydrogen bonds present in its composition, allowing it to cross the lipid bilayer without having its conformation and structure disassembled.
<span> It is a hydraulic </span>system<span> used by echinoderms, such as sea stars and sea urchins, for locomotion, food and waste transportation, and respiration. The </span>system<span> is composed of canals connecting numerous tube feet.</span>
