<span>A low white blood cell count usually is caused by: Viral infections that temporarily disrupt the work of bone marrow. Certain disorders present at birth (congenital) that involve diminished bone marrow function. Cancer (or other diseases that damage bone marrow)</span>
Answer:
Biotic factors are all of the living organisms within an ecosystem. These may be plants, animals, fungi, and any other living things. Abiotic factors are all of the non-living things in an ecosystem. ... Abiotic factors are especially important because they directly affect how organisms survive.
Explanation:
There are plenty of plants producing oxygen by photosynthesis.
Also, human's only use 5% of the oxygen in the air in respiration, there is 21% in the air.
