This question is incomplete as the specific food chain is not provided. In general, a food chain will have a primary producer at the base of the chain. This is an organism that is able to utilise a form of energy to convert carbon dioxide in the atmosphere to a carbohydrate. For terrestrial food chains, these are typically plants, who by utilising the energy from the sun, are able to convert carbon dioxide to carbohydrates. The subsequent level in the food chain may be a primary consumer, typically herbivores, that consume plant matter. Subsequent links in the chain would typically be secondary consumers, who would be carnivores, omnivores or decomposers. Carnivores would typically be predators and would be at the apex of the food chain. Energy is lost from one link to the subsequent link in the food chain, through basic respiration and inefficient energy transfer from one link to another. This explains why more resources (land, water and air) are required to grow meat rather than plant matter. More of the sun's energy is available within the lower trophic levels in a food chain, before much of it is lost as energy moves up the food chain. An easy example to illustrate this is that much of the livestock raised in the USA is fed grain. If people rather ate the grain than the livestock, they could obtain all their required energy from a smaller amount of grain then would be needed to raise the meat they require.
Answer:
The correct answer is a. sugar
Explanation:
Even though caffeine is also known for uprising the energy levels to a point where it could cause insomnia, the excess of sugar usually causes an increase in heart rate and insomnia. Also, coca-cola has a bigger amount of sugar than caffeine, so it explains how these high quantities could affect Xi's health.
Answer:
The correct answer would be B. semi-permeable.
Plasma membrane of any cell including red blood cell is semi-permeable in nature as it is made up of lipid bilayer.
It permits the passage of certain substances across the membrane while it blocks other substances.
Gases, small uncharged or non-polar substances such as oxygen, carbon dioxide, et cetera can easily pass through the cell membrane of a cell.
Large or charged molecules such as proteins, sodium ions, potassium ions et cetera can not pass through the cell membrane. They require carrier proteins to pass through the membrane.
Answer: Genetic Variation
Explanation: It is the presence of differences in sequences of genes between individual organisms of a species.