Answer:
Carboxylic acid.
Explanation:
Amino acids are made up of the amine group, carboxyl group, hydrogen and R hydrophobic chain. Amino acids are the monomers of the protein and they are coded by the particular codons.
Amino acids contains both the amino group and the carboxyl group. The carboxylic group is a polar group and becomes negative charged when the pH of the solution is greater than the pKa value of the amino acids.
Thus, the answer is carboxylic acid.
Answer: Valves in the veins
Explanation: The flow of the blood inside the body takes place through the veins and arteries. The oxygenated blood from the heart is supplied to the different parts of the body.
The blood flows from the capillaries to the venules and from there to the veins. The blood moves in the veins by the rhythmic movement of the smooth muscles in the body.
Most of the blood moves against the gravity so there is a chance that it can backflow so to prevent this there are valves in the veins known as one way valves.
Answer:
it depends on changes in gene expression
<span>The answer is shared an evolutionary
history. Homologous structures evolved
from the same ancestor structure. An example of homologous features is the four
limbs of all tetrapods. In birds, the forelimbs evolved
into wings while in crocodiles they still used for walking, and in humans, they evolved into hands. </span>