Small intestine is modified due to the presence of micro villi which has ability to increase it's size
D the expansion of their territory
You forgot to add the answers but a non living factor that could contribute could be something like temperature.
Answer:
The size of a population of microorganisms in liquid culture may bemeasured by counting cells directly or by first diluting the original sample and then counting cell numbers (see below), or by taking some indirect method such as the turbidity (cloudiness) of the culture.
Explanation: