The answer would be B.) Sweat gland
<span>The motor unit that is activated first and takes less energy is classified as low-threshold. The motor unit that is activated second and takes more energy is classified as high threshold. Sol lifting the labbook and placing it in the book bag simulates more motore units.</span>
Point A when inhalation begins
<span>Physical activity is the movement of the muscles and limbs of the body and this gives the physical fitness and keeps your body healthy. lack of this physical activity may leads to health problems. So no physical activity brings health problem called as hypokinetic problems.</span>