Answer:
Carbon dioxide, Oxygen
Explanation:
The circulatory system of our body works following two pathways -
In pulmonary pathway the deoxygenated blood is carried to the lungs while in the second pathway, known as systemic pathway, the oxygenated blood is carried to the various parts and organs of our body. Thus the completed sentence in the question will be -
Blood being pumped by the heart is circulated in two circuits. One circuit carries blood with high levels of carbon dioxide to the lungs, and the other circuit carries blood with high levels of oxygen to the body.
Answer:
It takes place in the absence of oxygen
The parathyroid glands is group of tiny glands that is located in the neck which controls the calcium levels of the body. This gland produces parathyroid hormone (PTH). This hormone raises the blood calcium level by breaking down the bone causing the release of calcium. It also increases the ability of the body to absorb calcium from the food that we eat and it increases the ability of the kidney to hold on to calcium that would be lost in the urine later on.
The regulation of calcium levels in the body is crucial for the heart, nervous system, kidneys and bones to function normally.
Therefore, the answer is parathyroid glands.
Answer:
7 - sun
8 - its energy requirements are unbelievably, terribly high
9 - fission
10 - radioactive waste material, for example from the use or reprocessing of nuclear fuel.
11 - The Nuclear Regulatory Commission licenses and regulates civilian use of nuclear energy to protect public health and safety and the environment
12 - ?
13 - ?
