Answer:
four
Explanation:
Carbon atoms have four electrons in their outer shell. So, it exhibits tetravalency & thus, a single carbon atom can form a maximum of four (4) bonds with other atoms
 
        
             
        
        
        
Vascular tissue is responsible for transporting water and nutrients in plants. The correct answer in regards to the given question is option "c". The Vascular tissue consists of the Xylem and the Phloem. The main function of the Xylem is to transport water and minerals throughout all parts of the plant. Phloem on the other hand is responsible for transporting organic molecules that are larger in size. The vascular system, consisting on the Xylem and the Phloem runs from the roots of the plats through the branches and upto the leaves. It controls the total transportation of the water and nutrients.
        
             
        
        
        
Answer:Type I interferons help protect cells from viral infection. The correct option is B.
Explanation:
Type I interferon (IFNα/β) is a type of cytokine that provides one of the first lines of host defense against viral infection.
Type I interferons act in a paracrine manner such that it have numerous effects on the surrounding cells, preparing them to ward off possible infection. The primary function is to induce protection against viruses in neighboring, non-infected cells. In the target cells they cause digestion of viral DNA and viral proteins.
 
        
             
        
        
        
Answer:
the breathing rate with volume of each breath increases to bring more oxygen into the body and remove the CO2 produced. the heart rate then increases, to supply the muscles with extra oxygen and remove the carbon dioxide produced often in the form of exercise.
Explanation: