DNA model given by Watson and Creek in the year of 1953 gave a very detailed study regarding the structure of B DNA which is valid till date and is essentially corroborating with Chargaff's data and Xray diffraction pattern. 
<h3><u>Explanation:</u></h3>
The DNA is the most common nucleic acid found in the living organisms as a genetic material. As stated by Watson and Creek, this DNA contains a double helical structure with two sugar phosphate backbones and the nitrogen bases getting projected from it inwards. The backbones are formed of ribose sugar and phosphate and joined together with a phosphodiester bond. The ribose sugar is attached to phosphates at its 3' and 5' Carbon atoms. The nitrogen bases found in DNA are Adenine, Guanine, Thymine and Cytosine. The Adenine has two hydrogen bonds with thymine and guanine has 3 hydrogen bonds with cytosine.
Each full turn of a helix is 34A and each base pair is 3.4A apart. The distance between two strands of DNA is 20A.
Chargaff's rule regarding the equal amount of adenine and thymine as well as guanine and cytosine is matching with this structure. All the other rules also do match with this DNA structure. 
 
        
             
        
        
        
Answer:
D. ABSORPTION
Explanation:
Connective tissues are a type of tissue, made up of ground substance, fibers and cells. 
Connecting tissues perform tissue support function using collagen, elastic, reticular fibers. 
It is also involved in transport of substances using hemoglobin in blood for transport of nutrients and oxygen, insulating the body, storing of fuel. 
 
        
             
        
        
        
Answer:
d.
Explanation:
Your body uses two types of molecules for storing energy, the carbohydrates are the main type and its used for short term storage, and for immediate use by the body. And the lipids or fats, are used for long term storage in the body, because they can store more energy in the same volume than a carbohydrate. 
 
        
             
        
        
        
Answer:
If all the trees are dark-colored  (without lichens) like the tree on the right, the moth that would most likely survive longest is the dark-colored moth.
Explanation:
This is because of natural selection (which means "A process in which individual organisms or phenotypes that possess favourable traits are more likely to survive and reproduce: the differential survival and reproduction of phenotypes.") The dark-colored moth is best adapted to its surroundings compared to the light-colored moth, and it will survive the longest (of the two) according to this definition of natural selection.
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