1) the manipulative variable is the salt
2) the responding variable is how many purple eggs hatched
3) beaker A was the controlling variable
Griffith's experiment worked with two types of pneumococcal bacteria (a rough type and a smooth type) and identified that a "transforming principle" could transform them from one type to another.
At first, bacteriologists suspected the transforming factor was a protein. The "transforming principle" could be precipitated with alcohol, which showed that it was not a carbohydrate. But Avery and McCarty observed that proteases (enzymes that degrade proteins) did not destroy the transforming principle. Neither did lipases (enzymes that digest lipids). Later they found that the transforming substance was made of nucleic acids but ribonuclease (which digests RNA) did not inactivate the substance. By this method, they were able to obtain small amounts of highly purified transforming principle, which they could then analyze through other tests to determine its identity, which corresponded to DNA.
The hawk, a carnivore (animal meat-eater), is predating on the rabbit, an herbivore (plant-eater). So the hawk can be seen as the predator and the rabbit as the prey.
But another type of relationship important in Ecology is consumers. So producers are the plants that feed a food web. That makes the rabbits the primary consumers (herbivores) of these plants. Then the hawks become the secondary consumers (carnivores) of the primary consumers, by eating the herbivores.
Hope that this makes sense!
Cell wall is the outer permeable covering in all pants and almost all prokaryotes ! cell wall are mainly made up of cellulose , sometime by chitin!!