Which discovery is attributed to phoebus levene? extraction and observation of dna identification of ribose and deoxyribose recognition of rna as dna’s messenger construction of an accurate dna model

The right answer is identification of ribose and deoxyribose.

Levene proved in 1900 that nuclein was found in all types of animal cells analyzed. Later, in 1909, while verifying the experiments of Albrecht Kossel, he showed that nucleic acids were composed of phosphoric acid, a pentose and nitrogenous bases. Levene showed that the pentose that appeared in the yeast nuclein was ribose, but had to wait until 1929 to identify deoxyribose pentose isolated from the animals' thymus. This difference made him propose that the nuclein of the animals was the deoxyribose nucleate -now called "deoxyribonucleic acid" or DNA, while the vegetables contained ribose nucleate or ribonucleic acid or RNA.

the answer is D on edgen.

Explanation:

the abdomen (less formally called the belly, stomach, tummy or midriff) constitutes the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. the region occupied by the abdomen is termed the abdominal cavity. the stomach secretes acid and enzymes that digest food. ridges of muscle tissue called rugae line the stomach. the stomach muscles contract periodically, churning food to enhance digestion. the pyloric sphincter is a muscular valve that opens to allow food to pass from the stomach to the small intestine.