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:
$55,400
Explanation:
To determine the cash paid for salaries and wages during the year.
wages payable (beginning of the year) = $800
wages payable (end of the year) = $2600
Income statement on wages and salaries for the year = $57,200
cash paid for Salaries and Wages during the year = (Salaries and Wages Expense + wages payable at the beginning of the year) - wages payable at the end of the year
$(57,200 + 800) - $2600
$(58000-2600)
= $55,400
Answer:
An index fossil is also known as guide fossils or indicator fossil. They are fossils used to determine and identify geologic periods.
The main characteristics of an index fossil include :
1.It must be distinctive.
2.It must be widespread.
3. It must be abundant
4. It must be limited in geologic time.
Due to trends and studies of most fossil-bearing rocks being formed in the ocean, the major index fossils are mostly marine animal or plant organisms.
The difference is very small, if it exists at all. Please Mark Brainliest!
Answer:
From the time of origin of life on earth has chaged many ways. The earth has also changed from the time of its origin. Both lives on earth itself are dynamic.
Different geolgical phenomena such as volcanic erruptions, tectonic movement etc., have changed the configurations of continents. These changed environment of the continents have affected the lives on the earth.
The Earth is 4.8 billion years old, while the origin of life on the earth is 3.5 billion years old. Gradually these changes have given the chaces of variations, from which the suitable organisms are selected on the earth.
Explanation:
