Answer:
The correct answer is b. He determined that DNA contains four nitrogenous bases.
Explanation:
Levene was an American biochemist who studied the structure of DNA in the early 1900s and in 1920 he found that DNA consists of four nitrogenous bases that are Adenine, Guanine, Thymine, Cytosine.
He also found deoxyribose sugar and phosphate group and said that nucleotide is the basic unit of DNA which contains a ribose sugar with attached nitrogenous base and phosphate group.
He also concludes that an equal amount of adenine, guanine, thymine, and cytosine makes the DNA which is now known as tetranucleotide hypothesis. So the correct answer is b. He determined that DNA contains four nitrogenous bases.
Trees would help make a forest. Tall grass would help make a meadow. Hope this helps!
Answer:
Assist with flood reduction.
Explanation:
The Virginia watershed program was organized and directed the secretary of Agriculture to assist local governments in protecting them against flood during storms within the sub - basins of watersheds. The basis of the Virginia watershed programs is to assist the local governments to protect, restore and enhance local watersheds. It's provide both technical and financial support.
A watershed is an area of land that drains into a lake or river.
<span>This is probably caused by ill-fitting shoes putting pressure on certain areas of the foot and would be called a Corn.
In this context, corn refers to some sort of calluses that appear if we constantly use ill-fitting shoes. The pressure that caused by the ill-fitting shoes will create some sort friction that will make the skin on that area become thicken.</span>