<span><span>the relevant controlled variable is the frog's body temperature, heart rate, breathing rate, and blood pressure. The controlled is a neutral pH level of 7 for the water that the frog is placed in, so that it does not obscure the effects of the water temperature on the frog's physiological factors.</span>
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Answer:
Plant cell
Explanation:
If you are trying to observe a cell wall, you should look at a plant cell. There are only two different types of cells, which are plant and animal cells. The plant cell is the only one which contains a cell wall. Animal cells actually only have a cell membrane.
The right ventricle pumps the oxygen-poor blood to the lungs through the pulmonary valve. The left atrium receives oxygen-rich blood from the lungs and pumps it to the left ventricle through the mitral valve. The left ventricle pumps the oxygen-rich blood through the aortic valve out to the rest of the body.
<span>Nothing is likely taking place. During REM sleep, which is when dreaming usually takes place, the body is usually in a still state, with eye-twitching as the only movement that is experienced. The body usually does not do anything to "act out" the movements experienced in the dreams.</span>
