In experiment 2, why was the control included in the chemical treatment experiment?

a. to prevent contaminating species from killing the

e. coli

b. to give you a baseline of the expected extent of bacterial growth

c. all the answer choices are correct.

d. to make sure the results were not due to osmotic pressure submit for grading save and finish later

c.all the answer choices are correct.

Explanati on:

Because control are used as a reference to negate the normal conditions of the cells.

answer: decrease

a limiting factor is the one which decrease the abundance, distribution and causes extinction of the population of species in a ecosystem. here, predators including hawks, owls and snakes are the limiting factor for the population of mexican free tailed bat.   although bats are nocturnal animals as they forge for food at night these predators also may remain active during night which can decrease the population of the mexican free-tailed bats. also, these bats eat only one type of insects that are moths. the food can also be a limiting factor as all 400 members are dependent upon same type of food needs that are moths. the decrease in the moth population can cause decrease in population size of the mexican free-tailed bats.

therefore, the scenarios will most likely to decrease the population size of the mexican free-tailed bats.  

many other transport proteins, often called pumps, move materials against a concentration gradient. active transport drives molecules across a membrane from a region of lower concentration to a region of higher concentration. this process, shown in figure 5.1, uses transport proteins powered by chemi- cal energy.