ANSWER: None of the above options are correct.
Cardiac Output(CO) = Stroke Volume(SV) × Heart Rate(HR)
Therefore where HR= 90bpm and SV= 110ml/min,
CO = 90 × 110 = 9900ml/min or 9.9L/min.
EXPLANATION:
CARDIAC OUTPUT is the volume of blood being pumped by the heart into the systemic circulation per minute.
Cardiac output is the product of two variables, stroke volume and heart rate.
STROKE VOLUME is the amount of blood pumped out by the left ventricle in each contraction.
HEART RATE is the count of the number of times the heart beats per minute.
Due to the fact that the white blood cells can change their shape and squeeze in through smaller parts of the blood flow, they have the ability to protect the immune system from any infections. They able to move easily in the blood flow, meaning that they can stop any infections or illnesses that would have came the person's way. This is why a person that has more white cells is not ill that often because there are more cells able to reach that particular place of infection.
<span>The answer is A. A stable ecological niche leads to the absence of selection pressures, which in turn causes species to remain unmodified or in stasis. This can be simplified with an example: If there are just enough lions on an island and just enough buck for both species to survive without the lions starving or the buck being killed off, neither of the species would have to adapt to survive because their predator-prey relationship is stable. This means that they can continue to live in this state of stasis or equilibrium. </span>