Answer: 37.2 trillion cells
D. Photosynthesis only takes place in the light, while cellular respiration takes place in the light and dark.
Answer:
The correct answer is: positive feedback.
Explanation:
Positive and negative feedback are terms that are used to define the way a system is regulated by its products. For example, when the production of a certain substance <u>inhibits</u> its producer that is called <u>negative feedback</u>. On the other hand, when a substance <u>stimulates</u> its producer to keep secreting said substance, this is called <u>positive feedback</u>.
Estrogen is a hormone of great importance in the female reproductive cycle and is secreted by the follicle cells in response to the presence of FSH (follicle-stimulating hormone), released by the anterior pituitary when stimulated by the GnRH (gonadotropin-releasing hormone).
Estrogen appears at the beginning of the cycle to stimulate the development of the ovarian follicles, and the hormone levels continue to rise as the cycle advances. Up until the 14th day of the cycle, estrogen has a negative feedback on GnRH and FSH, but then it makes an abrupt change to now exert positive feedback on GnRH to stimulate the release of LH (luteinizing hormone), which will be responsible for ovulation.
The gas form of water is water vapor.
The atmosphere is divided into different regions, called layers. The layer closest to the surface is known as troposphere, after which comes the stratosphere. The stratosphere begins at an altitude of 10 miles above the surface of the earth and stretches up to 31 miles above the surface of the earth. It is the second layer of the atmosphere (beginning from the surface of the earth) and it is the region which contains ozone, which plays a vital role in stopping ultraviolet radiation from reaching the earth's surface.