Answer: C
Explanation: When four oxygen molecules bind up , the hemoglobin forms a compound called oxyhemogoblin
Babies are born with reflexes or programmed responses to certain stimuli, such as touch. These reflexes help ensure survival. But they also provide an opportunity for a baby to interact with the world. For example, the rooting reflex is elicited by gently stroking a newborn's cheek.
An antigen triggers a response from the immune system and an antibody is produced. All antibodies are immunoglobulins, therefore, the correct answer is immunoglobulin. More specifically, an immunoglobulin is a protein produced by plasma cells to fight and neutralize pathogens. To do so, the immunoglobulin has a specific region which is complementary to a specific region of the antigen. Immunoglobulin's mechanism of action is to bind to the pathogen and either block its action or trigger a response of other cells of the immune system.
Answer:
Darwin proposed the theory of natural selection to explain the process of evolution. According to Darwin’s theory of natural selection, all organisms have the potential to reproduce limitlessly irrespective of the fact that each species maintain a constant density over time. However, the struggle for existence, i.e. the competition among individuals for available resources to survive and reproduce, put a check on species density (D) and maintains it at a constant level (B). Survival of fittest is unequal ability of individuals to survive and reproduce based on suitability of their inherited characters to prevailing environmental conditions (A). It imparts the reproductive advantage to certain organisms which account for major part of the gene pool of the species. Thus, natural selection favors the individual with survival and/or reproductive advantage over others under existing environmental condition (E). Thus, the correct answer is option C.