The answer is mitochondria.
The Lock-and-key mechanism was first proposed by Emil Fischer which described as the enzymatic reactions whereby an enzyme with a single substrate binds temporarily to form a substrate complex.
The lock-and-key mechanism is usually associated with the complementary shapes of an enzyme with a single substrate, wherein the lock that is being referred to is the enzyme and the substrate is the key. One right sized substrate (key) fits into the active site (key hole) of the enzyme (lock).
The active site which is mentioned above is structurally complementary to the substrate. This is the temporary binding site on the enzymes. Just like a lock and key, the enzyme as the lock and the substrate as the key is said to fit together.
The human body has living cells that interact with other living cells (Food) and inorganic cells (Salt, Oxygen). It also has a lot of chemical reactions that simultaniously happen inside of it.
Inorganic systems usually do not interact with themselves, and the reactions are mostly exterior.
Answer: B.) More research is needed to reach a conclusion, including related variables
Explanation:
As it is evident that oxygen is necessary element for living beings. It is required for the process of respiration, in which the food particles are broken down in the presence of oxygen into simpler substances.
Applying this knowledge to the given study suggests that all organisms require oxygen which can be less or more depending upon their habitat either in the shallow waters or in the depths. This conclusion is invalid and requires more explanatory approach which can be achieved by more research so as to derive a valid conclusion in which the two variables oxygen and relative habitats can be compared.
