Answer:
The correct answer is- phosphorus and sulfur
Explanation:
Hershey and Chase used radioactive phosphorus and sulfur to label T2 bacteriophage. Then they infected E.coli with these bacteriophage labeled with radioactive phosphorus and sulfur.
After infection, they centrifuge the cell and found that radioactive phosphorus is present in the bottom and radioactive sulfur in supernatant . As sulfur is mostly the part of protein not DNA and is found in supernatant and phosphorus is mostly present in DNA not protein which was found in cell debris, therefore, it was proved that DNA is the genetic material.
Genetic Engineering. They are changing the genes of something (In this case, Cabbage) to help is survive its environment better.
6. a, 7. c, 8. b , 9. e , 10. d , 11. e, 12.c
Answer:
) Presence of specific glycoproteins on the cell membrane
Explanation:
When specif glycoproteins(antigens) or antibody are present on a cell membrane of Red blood cell,they can be used to identify the blood type.Antigens are substances capable of triggering an immune response in a cells.
In addition,they function in transport of molecules across the RBC. They help in the maintenance of the RBC,and aiding the arrest of cells capable of causing diseases to the body.
Therefore,they are good determinants of blood types,based on this two types of antigens present in a blood type.
These two antigens used for classification of blood types are the 1-the ABO antigens 2,the Rhesus antigens.
Essentially,when a WBC produces an antibody ,which is a molecule that defends the body,If this is not compatible,the antibody will recognize it as a foreign body and attack it.Thus such blood types are not compatible. Thus the antibody-antigen reaction are good for knowing and classify blood types.
Antigen can also be glycoprotein,carbohydrate or glycolipids.
Generally blood types are inherited from both parents.Therefore the antigen present on the RBC are combination of the alleles from each parent.