Solar energy provides the reducing power within green leaves to convert CO2 and H2O into sugars. ... During illumination, leaf cells have both a source (respiration) and sink (photosynthesis) for CO2. Respiration in some species appears to be greatly stimulated by light.
Answer: Pulmonary aortic valve
Explanation:
The kidneys.
The kidneys keep blood isotonic by removing excess salt and water through urine.
Answer:
b. They express the appropriate receptor.
Explanation:
The signal transductions are extraordinarily specific and sensitive. Specificity is achieved by a <u>precise molecular complementarity between the signal molecules and the recepto</u>r. For example, the thyrotropin-releasing hormone produces a response in cells of the adenohypophysis, but not in hepatocytes, which lack the receptors to this hormone.
