Answer:
The left side of the heart receives oxygenated blood from the pulmonary vein and pumps it into the aorta, while the right side of the heart receives deoxygenated blood from the vena cava and pumps it into the pulmonary vein. The pulmonary vein and aorta also have valves connecting them to their respective ventricle.
Explanation:
Answer:
Option A, by having a constant supply of blood
Explanation:
Blood that flows to the muscles bring oxygen from the atmosphere to the contracting muscles where it gets consumed. During large muscle exercise, two physiological needs arise – a) high and prolonged muscle blood flow and b) regulation of blood pressure so that there is adequate perfusion of pressure to all organs. In order to meet both the requirements, the blood flow increases so that the vasoligating muscles do not outstrip the cardiac output.
Hence, option A is correct
Answer:
a. Stabilizing selection
Explanation:
Babies lower than 5.5lbs would suffer from various disorder because of low birth weight as their body would not be able to compete as well they would have weak immune system and malnourishment. Whereas high birth weight carry the equally above risk as their body wont be able to cope up and organs become insensitive to various hormones. for the survival the birth weight should be within a median range so that it would be favorable for themselves and surroundings.
Stabilizing selection occurs when a population stabilizes on a particular trait value and genetic diversity decreases. As in this example, an average baby weight has to favour against extreme variation for it's better survival.
therefore, this is an example of stabilizing selection.
