Aphotic zone of a body of water refers to the part where almost no sunlight. With this condition of water, marine life is limited to species who does not light for survival. The aphotic area also is the basin of the dead organism that submerges from the photic part. Temperatures at these areas are also low.
Answer:
The correct answer is option A.
Explanation:
Cellular organization is one of the characteristics of life that states that each living organism is made up cell or more than one cell, that is made up by organization of various components such as chemicals like micro molecule that form the macro molecule and these chemical level structural organization is formed together to make cells and this level of organization makes the tissue which is complex to cell but simpler to organ that is makeup of various together.
The makeup of organs is necessary as organs are the structural level that individuals facilitate the function and make up the organ system that is a complex system made up of organs that are similar in their function. The organism is the most complex of all levels.
Thus, the correct answer is option A.
The answer is; concentration of oxygen and/or total atmospheric pressure is lower at high altitudes
This means that at high altitude, due to the low pressure, every breath has a lower oxygen content than at a lower altitude. This, therefore, necessitates the body to increase the erythrocyte numbers in the blood to maximize the uptake of oxygen from the thinner air.
Answer:
Sister chromatids.
Explanation:
Sister chromatids are the two identical halves of a chromosome that are held together at centromere with help of cohesin. DNA replication in the S phase of the cell cycle doubles the amount of DNA. The copies of the DNA formed during DNA replication are accommodated in sister chromatids. Hence, two sister chromatids of a chromosome carry the identical DNA helices and associated proteins.