Jan Ingenhousz discovered photosynthesis
The Major function of the respiratory system is to exchange oxygen and carbon dioxide. Inhaled oxygen enters the lungs and reaches the alveoli, the layers of the cells lining the alveoli and the surrounding capillaries are each only one cell thick and are in very close contact with each other, the barrier between air and blood averages about 1 micron in thickness. Oxygen diffuses quickly through the air-blood barrier into the blood in the capillaries. Similarly, carbon dioxide passes from the blood into the alveoli and is then exhaled.
Answer:
A. increase in American pika population size
Explanation:
Carrying capacity is the idea that relates to how much population can an environment sustain before collapsing. Here, the answer would be A. increase in American pika population size because if you increase the food for weasals, naturally the population carrying capacity goes up because now the environment has food to feed the weasals which can contribute to increasing the carrying capacity (i.e. the environment can now handle larger population of weasel than initial condition)