1. 25% which is bb
2. All living things are made of cells
3. Grams, mass
Hope that helps.
Answer: No
Explanation: if a nucleic acid contains uracil then it is not DNA it's an RNA. Uracil is the basic nitrogenous base of RNA. DNA does not have Uracil in its structure. It contains thiamine instead of Uracil. So the answer is NO.
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.
My Answer: <span> lower than terrestrial planet densities, lower than the density of rock.
Hope I helped! :D
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