Answer: D
Explanation: endocrine gland cells that secrete hormones (chemical messengers), which are carried in the bloodstream to the target cells which they act upon
Answer:
False
Explanation:
Scientist believe that the primitive atmosphere lacked free oxygen. Oxygen is a highly reactive molecule that would have made difficult for complex macromolecules to appear and then create life. Rocks from the precambrian period support this theory.
Anaerobic cells appeared first, then photosynthesis appeared filling the atmosphere with oxygen and the aerobic organism develop cellular respiration to obtain energy, a process more efficient than anaerobic respiration.
The answer is; Benedict’s reagent
It is used to test for reducing sugars. In presence of these sugars, the reagent, that is blue in color, turns different shaded of red (to brick red), depending on the amount of reducing sugars in the solution. It is important to note that the solution has to be heated.
