The answer is light.
One of the factors that affect photosynthesis is light. Without light, the photosynthetic rate is reduced or even stopped which consequently affect algal growth. With increasing depth in the ocean, there is less sunlight present. Still, a<span>lgae have accessory photosynthetic plastids other than the chloroplasts</span><span> that can absorb different light in greater ocean depths. This helps them to maximum use sunlight in such conditions. But, in the end, at some particular depth, they would not be able to survive.</span>
Answer: Capillaries connect the arterial system — which includes the blood vessels that carry blood away from your heart — to your venous system. Your venous system includes the blood vessels that carry blood back to your heart. The exchange of oxygen, nutrients, and waste between your blood and tissues also happens in your capillaries.
Mitosis refers to the procedure of cell division, in which a cell goes through a carefully mediated nuclear division, which results in the production of two genetically similar daughter cells. The mitosis comprises five active stages, that is, prophase, premetaphase, metaphase, anaphase, and telophase.
In a single-celled species like an amoeba, it is the process of mitosis by which the cells reproduce. After undergoing through the five stages of mitosis, it is via the procedure called cytokinesis, the single cell dissociates into two similar cells, thus, completing the reproduction.
During injury, the process of mitosis takes place to substitute the damaged cells. This repair is mainly essential for the blood vessels and skin that safeguards the organs and muscles in the body. Mitosis also assists to substitute the lost blood via a wound.
Thus, if the process of mitosis would not take place, then the organism would remain a single-cell, asexual reproduction would not take place, and the tissues of the body would not be able to repair themselves.
I haven't taken biology since my freshman year of high school, so this is kind of a guess. But I know for sure it isn't a solid. So I would go with a gas.