Answer:
The correct answer is rRNA plays an important role during translation (protein synthesis) of mRNA.
Explanation:
Ribosomal RNA or rRNA are the RNA molecules which build up the site for protein synthesis known as ribosomes.
Ribosome synthesis takes place in nucleolus where two types of rRNA molecules associates with proteins, one in large subunit and one in the small subunit to form ribosomes.
These ribosomes physically moves along an mRNA molecule and catalyze the assembly of amino acids where rRNA molecules performs the catalytic steps of protein synthesis that is stitches amino acids together and makes up proteins.
Thus, rRNA plays an important role during translation (protein synthesis) of mRNA.
When a specimen is to be observed under the light microscope, scientists usually stain the specimens using different type of chemical stains depending on the type of specimen to be observed. Staining of specimen make the structures that are to be observed in the specimen very visible under the microscope, this make it easy for scientists to observe their structures.
Answer:
Emphysema ;A condition often caused by smoking,
Bronchitis ; The inflammation of bronchioles in the lungs
Asthma ; A condition in which an attack can trigger
Pneumonia ; The build up of fluid in the alveoli of the lungs
Explanation:
I hope it helps :)
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.
Two examples of organisms who do not reproduce sexually are:
1. Yeast
2. Hydra