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: zooplankton, small nekton
Explanation:
Answer: B
Explanation:
I think it is either A, B. I think it is B because Butter is a saturated fat and is saturated with hydrogens. This makes it solid. They are made from animal fats that contain saturated fatty acids that are solid at room temperature. Soft margarine is made of plant fats which remain liquid at room temperatures like the corn oil. -I searched this up UnU Hope this helps.
Answer:
bicycle I may be wrong sorry
The sensory receptors located on a frog's head assist it in the water through protection and flotation. The receptors hold the frogs head above the water, and the frog uses this as an advantage to see if there is any predators or prey around to help it survive. Hope this helps!
