Answer:
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Explanation:
In a cell protein synthesis is the primary function of ribosomes
The answer to the question stated above is non-disjunction.
Complete Question:
Which of the following might stimulate the cephalic phase of gastric secretion?
A. stomach distention
B. the production of saliva
C. the thought of food
D. the production and secretion of gastrin.
Answer:
C. the thought of food
Explanation:
Gastric secretion usually occurs in three different phases, namely;
- Cephalic
- Gastric
- Intestinal
The thought of food usually stimulate the cephalic phase of gastric secretion in organisms. The presence of lipids or low pH inhibits Gastric secretion during the intestinal phase.
Answer:
The correct answer is: Yes, this is an example of Reproductive Isolation.
Explanation:
- Reproductive Isolation can be defined as the mechanism adopted by different species during the course of their evolution, due to which the individuals belonging to different species are incapable of mating with each other and producing viable offspring.
- The given question is an example of Mechanical, Pre-zygotic Reproductive Isolation.
- Prezygotic Isolation refers to the mechanism adopted by individuals of different species during the course of evolution such that successful fertilisation of gametes from individuals of different species never occur, hence a viable zygote is never formed.
- Mechanical Isolation refers to the mechanism adopted by individuals of different species during the course of evolution such that their reproductive organs or the organs that assist in the process of reproduction are incompatible to each other. Hence, the gametes of each species are unable to come in vicinity of each other.
- Here, the pollen grain from the flower of one species of juniper is unable to form the pollen tube when its sits on the stigma of the flower of another species of juniper. This is an example of Mechanical Isolation.
