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.
Answer:
Palatilism
Explanation:
Due to one organism benefiting (tapeworm ) while the other organism is harmed (dog)
Starch cannot diffuse across the membrane because starch molecules are too large to fit through the pores in the dialysis tubing, whereas iodine is a smaller molecule and therefore can diffuse across.
There are three main stages to get from food molecules to ATP: glycolysis, the citric acid cycle, and the electron transport chain.
