A division between two opposite characteristic is known as a dichotomy. This is correct since the definition to the word is "two things being totally opposite or entirely different." The correct answer is A.
Answer:
D In Prophase I the chromosomes crossover, in Prophase II they do not crossover
Explanation:
Meiosis is a type of cell division in which four daughter cells, which are genetically different from one another, are produced. The daughter cells have their chromosomal number reduced by half. Since, the meiotic process aims at producing haploid gametes, it occurs in a series of two-division steps viz: meiosis I and meiosis II.
Meiosis I involves the separation of homologous chromosomes into two daughter cells while the meiosis II involves separation of chromatids to make four daughter cells. One major difference between meiosis I and meiosis II is that in the PROPHASE of meiosis I, a unique process called CROSSING OVER occurs but does not occur in meiosis II (as seen in the attached image).
Answer:
Here, the stimulus which is discussed in the question is the Suckling stimulus which is also known as Suckling reflex.
Suckling by a child stimulates the suckling reflex system. The stimulus (information) reaches to the Hypothalamus. Hypothalamus triggers the TRH (thyrotropin-releasing hormone) which further triggers the releases of the Prolactin (PRL) hormone by the Anterior Pituitary.
Finally, when Prolactin reaches the blood, it stimulates the Mammary glands which being stimulated, start to produce milk.
Explanation:
The main function of Prolactin is to produce milk. Prolactin production is mainly controlled by Hypothalamus. Prolactin hormone is produced in Pituitary, uterus, etc. The prolactin hormone production is also controlled by the estrogen.
- Prolactin regulation is also controlled by Dopamine and Oestrogen. Both of them regulates the onset and stoppage of prolactin production by sending the information to the pituitary gland. Dopamine mainly blocks the production when the level of prolactin is too high in the blood. Oestrogen mainly increases the production when the level of prolactin in the blood is too low.
- Not only Prolactin boost up the milk production but it also helps in maintaining the female's body metabolism, immune system, regulating the menstrual cycle, and regulating body fluid levels. In males, it increases sperm production.