The given question is incomplete. The complete question is:
In humans, the maintenance of a stable internal temperature is a direct result of___________.
a. detection of and reaction to stimuli in the environment
b. digestion of starches and absorption of protein from the internal environment
c. diffusion of water and excretion of glucose to the external environment
d. transport of ATP and locomotion through the environment
Answer:
a. detection of and reaction to stimuli in the environment
Explanation:
Thermoreceptors present in skin layers of the human body sense the deviation of the body temperature from the normal range. As the body temperature rises above normal, the thermoreceptors send signals to the brain which n turn signals dermal blood vessels to dilate and sweat glands to secrete sweat. The heat from the body surface is lost to the surroundings to drop the body temperature towards the normal range.
On the other hand, when the body temperature goes below the normal range, thermoreceptors send signals to the brain which in turn signals dermal blood vessels to constrict to conserve the body heat. If body temperature continues to drop, muscles are signaled to contract involuntarily to generate body heat to raise the body temperature towards the normal range.
Cell membrane fluidity is determined by many things, including the presence of or absence of saturated and or unsaturated fatty acid tails, and because of that the ability of the phospholipids in a cell membrane to tightly pack together or not. I believe though in terms of an additional substance it would have to be cholesterol. These specific lipid molecules are inserted in between the phospholipids preventing phospholipids from tightly packing together thus allowing the cell membrane to have greater fluidity and flexibility.
<span>Scientists found that the cytoplasm of cells undergoing mitosis, if injected into cells at other stages of the cell cycle, could induce the non-dividing cells to start mitosis. This suggested that a chemical signal was present in the cytoplasm of dividing cells that was responsible for "telling" the cells that they should proceed into mitosis. By fractionating the cytoplasm into its components, scientists were able to isolate the signal that triggers mitosis.</span>
Deep sea creature. These are animals that usually eat decaying matter or sea animal carcass sinking in the floor of the ocean. This is an ocean zone where in there is a high water pressure, no sunlight reached the area, and extremely low temperatures. The area where they live is called abyssal zone. The condition is very harsh where in they need to adapt in the enrinment through bioluminescence. Organism produce light through chemical reaction and chemosynthesis they transform energy from the chemicals available.
