Answer:
The correct answer is option C. secrete chemical messengers that travel in the bloodstream.
Explanation:
Endocrine glands are organ or gland that secrets hormones that are chemical messengers travel through the bloodstream instead of the duct. There are several glands that are part of the endocrine system such as the thyroid gland, pancreas, hypothalamus, and others.
These chemical agents are the travel through the blood and act on the site of action.
Thus, the correct answer is option C. secrete chemical messengers that travel in the bloodstream.
Oxygen is what animals need in order for Carbon Dioxide to be exhaled while breathing. This is part of what the Respiratory System does. Carbon also enters animals that are in contaminated environments such as living next to a factory or a polluted area.
<em>Chemical weathering is most effective in;</em>
C) A warm, moist climate
<u>Chemical processes need water, and occur more rapidly at higher temperature, so warm, damp climates are best.</u>
Electromagnetic waves diffract around the cell phones antenna