Answer:
The correct answer is - the cell membrane.
Explanation:
When a human cell gets an external stimulus it triggers the production of the specific compound or chemical release which is packed in vesicles from the endoplasmic reticulum and Golgi apparatus to the cell membrane. The cell membrane is the cell organelle that allows or prohibits the entry or exit of any substance.
Chemical release or secretion also depends on the cell membrane and it allows the secretion of chemicals and plays an important role in the secretion of chemical, hormones, or any substance.
Answer:
Extrinsic regulatory mechanisms are external and depend on the firing of some factor outside the population itself. Among them are interspecific competition, food and space restrictions, very strong climatic variations, weathering and inharmonious relationships with other populations (parasitism and predatism).
Good examples of interspecific competition appear when rabbits, caves, rats compete for the same plant, or different fish and birds, such as the heron, vie for the same species of smaller fish. This is because these different species keep their populations in the same ecological niche. Competition is often so strong that some species eventually, as one example of an extrinsic homeostatic mechanism overriding an intrinsic homeostatic process is their disappearance or migration to other regions.
In this competition, the presence of adaptations among individuals in the population that promote better food search, speed, vision, and others can make the difference between elimination and survival.
All the organic molecules produced by autotrophs CONTAINS ENERGY.
Autotrophs are plants that produce their own food using energy from the sun. Products produced by these autotrophs contain inherent energy which humans and animals absorb when they eat these products.
Answer:
NAD is a coenzyme found in all cells. It consists of two nucleotides linked through their phosphate groups with a nucleotide that contains an adenosine ring and another that contains nicotinamide.
Explanation:
In metabolism, NAD participates in oxidation reduction reactions. This coenzyme is found in two forms in the cells: NAD and NADH. NAD accepts electrons from other molecules and is reduced, forming NADH, which you can use as a reducing agent to donate electrons. These electron transfer reactions are the main function of the NAD.
In living organisms, NAD can be synthesized from scratch from the amino acids tryptophan or aspartic acid. Some NADs are found in nicotinamide adenine dinucleotide phosphate (NADP), whose chemistry is similar to NAD, although it has different functions in metabolism.
