Answer: B. strong natural selection.
Explanation:
Speciation is the process by which new species form from the existing parent species. It occurs when the population of the species become reproductively isolated. In sympatric speciation the organisms living in the same geographical area becomes reproductively isolated due to changes in the behavior, morphology and genetic make up.
Among the option given, strong natural selection is the correct option. This is because of the fact that natural selection brings changes in the living being in terms of adaptation. The organism having better phenotypic trait will survive and reproduce. The beneficial traits will pass on to next generation may lead to evolution of new species. The members of the new species may not be able to breed with parent species.
Answer:
The correct answer is option D. Permissive.
Explanation:
The permissive effect or interaction of a hormone is in which hormone can not show or exert its complete effect without the presence of another hormone on a specific target site or cell.
The interaction of a hormone can occur in two more ways - synergies and antagonism where synergy occurs when two hormones perform the same action on a target cell and impact are amplified, and antagonist has the opposite role in the presence of another hormone.
Thus, the correct answer is - d. Permissive.
Option D
Research on the physiological states accompanying specific emotions indicates that each emotion has a unique pattern of sympathetic nervous system activity
<u>Explanation:</u>
Emotions are usually characterized by thinking and sense elements that point our consciousness and control our response. By the sympathetic portion of the autonomic nervous system, sensitive events followed by excitement feel and actions of the physical acknowledgments are produced.
Emotions enhance especially prominent in leading options when the dilemmas among various complicated and contradictory options confer us with a great measure of contingency and vagueness, proffering a comprehensive cognitive study challenging. Urges are powers that control the action. The cognitive evaluation also enables us to encounter a kind of trivial sensations.
Answer: If a husband and wife who are both carriers of the sickle-cell anemia allele (Ss) but do not have the disease decide to have a child, the offspring can be Normal (SS), carrier (Ss) or sick (ss) with the probability ¼, 2/4 (½) and ¼ respectively.
Explanation: If the mother contributes the dominant allele and the father also contributes the dominant allele, the genotype of the child will be SS. The probability is ¼. This means there is a 25% chance that a randomly selected offspring will be a normal child and will not have sickle-cell anemia.
If the mother contributes the dominant allele and the father contributes the recessive allele, the genotype of the child will be Ss. The probability is 2/4 or ½. This means there is a 50% chance that a randomly selected offspring will be a carrier of sickle cell anemia, but will not have sickle-cell anemia.
If the mother contributes the recessive allele and the father also contributes the recessive allele, the genotype of the child will be ss. The probability is ¼. This means there is a 25% chance that a randomly selected offspring will have sickle cell anemia.
Check attached image for illustrations.