According to all known laws of aviation, a bee
Out of the choices given, the reason why Kathy's body feels sore and she has pain in her limbs after vigorously exercising is an accumulation of lactic acid in the muscles of her limbs. The correct answer is A.
Some activities that cell requires energy may include cell division, active transport, protein synthesis etc.
In human, Cells get their energy by the food we eat. The nutrients in the food breaks down into soluble and simple molecules in stomach and small intestine and it is absorbed through the small intestine and assimilated into the cells, becoming part of it, providing the uses for each type of nutrient. And of course, many of them is the energy source.
