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.
You can do golden rice. It was genetically modified to produce beta carotene, which rice does not usually have. When metabolized by the body beta carotene is turned to vitamin A which is essential to human vision, immune systems, and healthier skin
Answer:
The human impact on the Amazon rainforest has been grossly underestimated according to an international team of researchers. They found that selective logging and surface wildfires can result in an annual loss of 54 billion tons of carbon from the Brazilian Amazon, increasing greenhouse gas emissions.
Explanation:
Answer: IV: the tire treads. DV: The braking distance of the car
Explanation:
Answer:
Enzyme- Peptidase/protease
Explanation:
According to this question, a student is conducting an experiment to determine the roles of molecules in metabolic processes such as digestion. Based on what she found out that the molecule, which itself can be broken down into amino acids, can also break down proteins into amino acids, this suggests that the molecule being described is a PROTEOLYTIC ENZYME.
This is because an enzyme is made up of proteins which can be denatured or broken down into its simplest unit (amino acids) and also, a substance that breaks down amino acid is said to be PROTEOLYTIC.
However, another observation that the molecule is found in high concentrations in the small intestine was made, hence, the enzyme is a PEPTIDASE OR PROTEASE, which are secreted into the small intestine by the pancreas to aid digestion of proteins.
