Answer:
The answer is number two extinction happened, this was the time dinosaurs went extinct ebcause lack of sun because oh how much dirt was blown into the earth atmosphere becuase of the asteriod, third option is talking about big bang theroy so that dosnt apply!
Explanation:
 
        
             
        
        
        
Recombinant DNA is DNA that has been created using intelligent design methods to modify a base DNA molecule using DNA component elements from other strands of DNA of other organisms. There are a wide range of possible DNA elements that can be removed, added to or otherwise modified to produce the new recombinant form. 
Recombinant DNA technology clearly is genetic engineering using intelligent design as the selection and placement of the added DNA components must be planned and precisely selected and placed to accomplish the intended result. It does not happen naturalistically.
There are numerous aspects of the growing technology of recombinant DNA that modify DNA to serve the purpose of the intelligent designers, including wide ranges of research, medicine, synthetic biology, potential commercial products and even scientific curiosity.
        
             
        
        
        
Answer:
The bonds that are formed between nitrogenous bases are Hydrogen Bond.
Explanation:
When a hydrogen atom  interract with an electronegative atom such oxygen,fluorine hydrogen bond forms,
               A single hydrogen bond is weak noncovalent bond but collectively  they exerts  very strong interraction.
             Hydrogen bonding occurs between complementary base pair .For exam An adenine base forms 2 hydrogen bonds with thymine base whereas guanine forms 3 hydrogen bonds with cytosine base.
              The hydrogen bonding between complementary is very much important to stabilize the structure of DNA . 
 
        
             
        
        
        
Answer:
A. The rice genes didn't make the right type of vitamin A.
Explanation:
Regular white rice does not have the gene to produce beta carotene. The human body converts the beta carotene into vitamin A. 
To increase the nutritional value of rice, the gene for beta carotene from daffodil flowers was inserted into the cells of endosperm of rice. 
This allowed these cells of the genetically engineered rice varieties to produce beta carotene. Production of beta carotene imparted golden color to the rice grain and hence, the name.
 
        
             
        
        
        
Answer:
Both gray wolves and killer whales have live births. And Both gray wolves and killer whales are carnivores
Explanation: