Answer: A sphincter is basically a hatch keeping stuff in and other stuff out of an organ such as the stomach. The pylorus is the muscle keeping the exit of the stomach shut, or opening it so that half-digested food may enter the duodenum to be digested further. The muscle ensures food can stay in the stomach long enough, and not flow right on through without being modified long enough by the stomach acids and digestive enzymes. It also regulates the amount of stuff that goes through.
Answer: The Inner Ear has two main parts that gives it its main function. The first one is the cochlea which is one of the three smallest bone in the human body. It is mainly functioning for hearing. The second one is the vestibular system. It is the one responsible for balance. The inner ear also converts sound waves into neural signals in a process called transduction and sends these neural signals out to the brain.
Answer: Arterioles are very tiny arteries. In some areas of the body there are places where arteries and veins come together in tiny formations to swap oxygenated blood (in the arteries) for unoxygenated blood (in the veins). (As the veins get smaller they become capillaries, then caprioles.)The arteries are responsible for delivering blood with oxygen from the lungs to the rest of the body. Veins carry the "used blood" with no oxygen back to the heart where it passes into the lungs and picks up more oxygen and gets rid of the carbon dioxide that builds up as our bodies use the oxygen. The arterioles and caprioles come together to swap this blood.Well the above might be true but......Arterioles are small arteries that deliver blood to the Capillaries. While Venules are small veins that are connected to the Capillaries.
Answer: there are a lots of reasons.. the most common one would be cold. when your body temperature decreases it causes the arterioles under the skin to constrict which results in decrease in heat loss from the body. the other reasons would be neurogenic vasoconstriction during minor trauma to skin, and many more less common causes.
Answer: Reproductive is to produce the next generation..
To regulate sexual activity. It is usually expected that sexual relations between men and women take place inside some kind of marriage relationship or pairing and that they are regulated by some social rules. Families exist to control sexual behaviour so that the new offspring are as healthy as is possible.