Active muscles demand huge amounts of oxygen, and the circulatory system works hard to provide it. Blood carries oxygen to the muscles. When the body is at rest, blood carries nutrients to the muscles so that they can repair and rebuild themselves. Blood also carries away the waste products that hard-working muscles produce, back out through the lungs to be filtered.
so they Circulatory system xx muscular system :)
Answer:
The ability of caffeine to inhibit adenosine receptors, plays a very important role in heightened alertness and sleeplessness.
Explanation:
"<em><u>Caffeine</u></em>" (<em>1,3,7-trimethylxanthine</em>) is an alkaloid obtained from plants. It has a chemical formula of C8H10N4O2.
Caffeine is generally <em>hydrophillic</em> but sufficiently <em>lipophilic</em> to pass through all biological membranes and readily cross the blood-brain barrier.
Therefore can bind with the adenosine receptors. Due to the blocking of adenosine inhibitory effects through its receptors held by paraxanthine and caffeine, it indirectly affects the release of <u>norepinephrine, dopamine, acetylcholine, serotonin, glutamate</u> e.t.c.
The release of the above-mentioned hormones have a great impact on the heightened alertness of the body, especially <em>dopamine</em> and <em>serotonin</em>.
Vitamin D plays a vital role in the regulation of calcium deposits and maintenance of the phosphorous levels in the blood which are two elements that are significantly important for maintaining healthy bones.
The human body needs vitamin D to absorb calcium in the intestines and to recover calcium that would otherwise be excreted through the kidneys. It also essential for the development and strengthening of bones and it blocks the release of parathyroid hormones.
The answer would be letter E. None of the above
It would be 2) two atoms exchange electrons and become ions
Answer:
A. eukaryotes and heterotrophic
Explanation:
Remember Fungi is not either bacteria or a plant. But we know Fungi has a membrane-bound nucleus that makes it eukaryotic. They obtain material from the enviroment, instead of creating their food, which makes them heterotrophic.
