Answer:
Option C
Explanation:
Given -
Total number of initially marked lizards (M) 
Total number of recaptured lizards (C) 
Total number of recaptured marked lizards (R) 
As we know that -
We have to find "N" . "N" is the total population size of lizards in a 2-hectare plot in eastern Arizona.
Thus, on rearranging the above equation, we get -
Substituting the given values in above equation, we get -
Hence, option C is correct
Answer:
The correct option is B (natural killer cells).
Explanation:
Natural killer cells: They are defined as the type of cytotoxic lymphocyte which are critical to the innate immune system. The NK cells play an important role in to provide rapid response to tumor formation, virus infected cells, and acting after three days of infection.
While cancer cells die, they release some antigens, than these antigens are recognized by the immune system, and later they are presented on the immune cells which are known as antigen presenting cells. So, if these cells are absent than they increase the chances of developing malignant tumors.
A biotic factor is a living thing that has an impact on another population of living things or on the environment. Abiotic factors do the same thing, but they are non-living. Together, biotic and abiotic factors make up an ecosystem. To survive, biotic factors need abiotic factors.
