Answer:
Watson and Crick proposed the double helical model of DNA.
Explanation:
- This model says that DNA exist as double helix. It has two polynucelotide strands running in opposite direction i.e the strands are anti-parallel.
- Each polynucleotide strand is made up of several nucleotide liknked together by phophodiester bonds.
- The two strands are not coiled upon each other but the double strand is coiled upon itself around a common axis like the spiral stair case. Here base pairs forms the stairs and backbone of two strands form railing. Back bone contains sugar and phosphate.
- The base pairing is specific, adenine always pairs with thymine and guanine always pairs with cytosine. Thus if we see any base pair, it consists of one purine and one pyrimidine.
- The two strands of DNA thus show complementary base pairing.
- The strands are held together because of hydrogen bonding between the bases in opposite strand.
- One full helical turn involves ten base pairs and the base pairs are stacked 3.4 A apart.
- This form is called as B-form of DNA.
Answer:
D
Explanation:
<em>They</em><em> </em><em>are</em><em> </em><em>not</em><em> </em><em>used</em><em> </em><em>by</em><em> </em><em>the</em><em> </em><em>bod</em><em>y</em><em> </em><em>on</em><em> </em><em>daily</em><em> </em><em>basis</em><em> </em><em> </em><em>bec</em><em>ause</em><em> </em><em>they</em><em> </em><em>ha</em><em>ve</em><em> </em><em>less</em><em> </em><em>nutrie</em><em>nts</em>
Answer:
It looks like a chinchilla
Explanation:
looking at the size, shape and tail it must be a chinchilla but i could be wrong but im pretty sure.
D. Geographic separation of a population
Answer:
a. Uncontrolled cell growth
Explanation:
Cancer is an irregularity that occurs when cells mutate in a harmful way. This causes abnormal cell growth that is uncontrollable. These cell growths become tumors that, based on the type, may or may not spread to other parts of the body.
