The answer is a. natural selection.
<span>In natural selection, genotype variations that will increase
the chance of survival and reproduction of some organism are preserved and will
be inherited. Darwin's theory suggested that there are variations among
individuals in a population and that these variations will help individuals to
survive. According to Darwin, natural selection is the only factor that affects frequency of different variations.</span>
Answer: B
Explanation:
If glucose and arsenate are both added to the cell extract, at first glycolysis will start.
In step one of glycolysis, glucose is phosphorylated to glucose-6-phosphate catalyzed by hexokinase which splits the ATP into ADP, and the Pi is added on to the glucose.
In step 3 of glycolysis, fructose-6-phosphate is further phosphorylated to fructose 1,6-bisphosphate. The enzyme is phosphofructokinase. This again involves hydrolysis of another ATP molecule.
A total of two ATP is used.
Step 6 in glycolysis reaction which involves generation of 2 ATP's molecules is inhibited by arsenate. Hence all other glycolytic reaction would not take place. Therefore no ATP is produced and pyruvate is not produced also.
ATP level decreases because ATP is only used up but no ATP is gained from the inhibited pathway. Also the inhibition of the step 6 enzyme cut short the pathway and pyruvate the end product of the pathway is not formed.
D. They had to see if this new idea fit the evidence they found in their experiments.
Communication refers to a state when one animal conducts information to another animal making a certain type of modification in the animal, which acquires the information. Animals generally communicate using signals that may involve visual, auditory or sound based; chemicals involving pheromones, and others.
A pheromone refers to a discharged chemical signal used to stimulate a reaction in another individual of the similar species. Pheromones are generally common among social insects, like bees and ants. It is used to fascinate the opposite sex, mark a food trail, raise an alarm, or to stimulate other composite behaviors.
This kind of communication plays an essential role in natural selection. It helps in obtaining mates, establishing defending or dominance territory.
