The nucleus always contains one or more protons.
During acclimatization over a few days to weeks, the body produces more red blood cells to counteract the lower oxygen saturation in blood in high altitudes. Full adaptation to high altitude is achieved when the increase of red blood cells reaches a plateau and stops.Heart rate is controlled by the two branches of the autonomic (involuntary) nervous system. The sympathetic nervous system (SNS) and the parasympathetic nervous system (PNS). ... At the beginning of exercise, your body removes the parasympathetic stimulation, which enables the heart rate to gradually increase.
D)all of them
Answer:
Hilum.
Explanation:
Hilum may be defined as the type of the depression or the fissure and may present in kidney known as kidney hilum, present on spleen and the lungs. This is also known as hilus.
The hilum marks the entry and exit of the nerves and the blood vessels. The lung hilum is a triangular like depression through which the blood vessels, capillaries and the nerves enter and leave in the lungs and connects the other organ of the body.
Thus, the correct answer is option (d).
