Answer: A) The 'lub' sound is caused as the atrioventricular valves close.
Explanation:
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<span>athlete’s foot, an itchy foot rash caused by a fungus</span>
Tissue(interstitial)fluid
Warm-blooded creatures, like mammals and birds, try to keep the inside of their bodies at a constant temperature. They do this by generating their own heat when they are in a cooler environment, and by cooling themselves when they are in a hotter environment. To generate heat, warm-blooded animals convert the food that they eat into energy. They have to eat a lot of food, compared with cold-blooded animals, to maintain a constant body temperature. Only a small amount of the food that a warm-blooded animal eats is converted into body mass. The rest is used to fuel a constant body temperature.
It is now a new chemical reaction and has different properties now.
