Answer:
They used radioactive labeling techniques to build two different types of phage.
Explanation:
In 1952, a set of experiments were carried out by American biochemists Alfred D. Hershey (1908-1997) and Martha Chase. They prepared two separate virus samples, one contained DNA labeled with a radioactive isotope and the other contained protein labeled with a different radioactive isotope. They grew the two types of viruses separately, infected bacteria with the two sets of phages and analyzed the bacteria for radioactivity. From the results obtained, Hershey and Chase concluded that the viral genetic material was DNA and not protein, reinforcing the observations previously made by Avery.
Answer:
c
Explanation:
Gas exchange. Gas exchange occurs as a result of respiration, when carbon dioxide is excreted and oxygen taken up, and photosynthesis, when oxygen is excreted and carbon dioxide is taken up. The rate of gas exchange is affected by: the area available for diffusion.
I believe the correct statement is that Water absorbs heat when it changes to vapor, helping to keep animals cool through perspiration. Water has a high heat of vaporization, the amount of energy needed to change one gram of a liquid substance to gas at constant temperature. In humans and other organisms, the evaporation of sweat, which is 90% water, cools the body to maintain a steady temperature.
Answer:
(i) Groundnut and mustard seeds are called oilseeds because they are used to extract edible oil which are used for cooking food.
(ii) Herbivores consume only plants and plant products whereas carnivores feed on other animals only.
Explanation: