A. Hormones act as signal molecules between all body systems
Peripheral Chemoreceptors (Carotid + Aortic Bodies) and Central Chemoreceptors in the Medulla Oblongata detect high Carbon Dioxide levels in the blood during exercise. The respiratory centre in the Medulla Oblongata + PONS stimulate the intercostal muscles and the diphragm to contract in order to increase the rate and depth of breathing as to decrease levels of Carbon dioxide in the blood.
The thyroid gland secretes thyroxine which speeds up metabolism (the rate at which cells use glucose)
Answer:
Option A, Hormones are controlled by a feedback loop; information about a system is sent back to the controller of the system to improve its function.
Explanation:
Negative feedback loop controls the hormone production and release. This is done by eliciting the release of substances till a certain level after which the stop signal is activated thereby preventing further release. By this method, concentration of hormones in blood is maintained within the narrow range.
For example – Thyroid hormones is released when the anterior pituitary signals the thyroid. This continues till the hormones in the blood reach the threshold level. Once the threshold level is reached, hypothalamus receives a feedback and then signals anterior pituitary to inhibit further signaling to the thyroid
Hence, option A is correct
Author's use of details convey to Eleanor Rossevelt life and legacy are described below.
Explanation:
1.She advocated for expanded roles for women in the workplace, the civil rights of African Americans and Asian Americans, and the rights of World War II refugees. Following her husband's death in 1945, Roosevelt remained active in politics for the remaining 17 years of her life.
2.The fireside chats were a series of evening radio addresses given by U.S. President Franklin D. Roosevelt (known colloquially as "FDR") between 1933 and 1944.
3..President Theodore Roosevelt, an Oyster Bay Roosevelt, was the uncle of Eleanor Roosevelt later wife of Franklin Roosevelt. Despite political differences that caused family members to actively campaign against each other, the two branches generally remained friendly.
4.Champions of Human Rights. Eleanor Roosevelt (1884–1962)
- Continuing her work on behalf of all people, she advocated equal rights for women, African-Americans and Depression-era workers, bringing inspiration and attention to their causes.
Answer:
Option D
Explanation:
The cornea is one of the most sensitive tissues of the body, as it is densely innervated with sensory nerve fibres via the ophthalmic division of the trigeminal nerve by way of 70–80 long ciliary nerves. Hence the answer would be option D.
Amoebas are single-celled organisms, which means that they are composed of just one cell. Each amoeba is a cell capable of performing all living functions by itself. They can reproduce asexually. They are protozoans with no fixed shape. Most have no hard parts and look like blobs of jelly.
