Answer AND Explanation:
There is a large number of biochemical reactions taking place in a cell at any given time. Enzymes being biological catalysts control these reactions and regulate them so that they proceed at a pace that is suitable for sustaining life. Thus enzymes regulate cellular activities. Enzymes also ensure that only the required reactions take place and progress to their appropriate extent.
Answer:
1 g/mL. Thus, 20 mL of pure water weighs 20 g.
Explanation:
B, Provide nutritional support to the embryo. It is not D, as the breasts are not part of the female reproductive system. It isn't C because during pregnancy, fetal and maternal blood do not mix. It also isn't D since women do not produce sperm.
During exercise, a number of changes occur to maximise the body's oxygen intake. Firstly our heart rate/ pulse increases. This is due to the heart beating much faster and more forcefully to pump blood faster around the body.
Our breathing rate increases to intake more oxygen and exhale more CO2.
The smooth muscle in our trachea and bronchi relaxes to increase the lumen size thus making breathing easier. Adrenaline may also be released leading further amplifying these changes as well as reducing blood flow to the gut and thus peristalsis occurs at a much slower rate.
Also when we exercise we respire more, producing heat, which must be expelled. This may be done through sweating. Another physiological change that occurs is vasodilation of arterioles closer to the skin to allow more blood to flow closer to the skin, allowing more heat to radiate out.