Answer options:
- extraction and observation of DNA
- identification of ribose and deoxyribose
- recognition of RNA as DNA’s messenger
- construction of an accurate DNA model
Answer:
- identification of ribose and deoxyribose
Explanation:
Phoebus Levene was an American biochemist who studied the structure of DNA and RNA. He was able to isolate the sugars (ribose and deoxyribose) from the nucleic acids, which are an important part of their structure.
He also determined how the nucleic acid components combine to form the nucleotides, the basic building blocks of nucleic acids, and how the nucleotides combine in chains to form the polymer.
Explanation:
Chemical digestion is a vital part of the digestive process. Without it, your body wouldn't be able to absorb nutrients from the foods you eat. While mechanical digestion involves physical movements, such as chewing and muscle contractions, chemical digestion uses enzymes to break down food. Make my inbox healthier.
Answer:
- Radial symmetry is advantageous because sessile animals can "sit down", take food, or sense harmful environmental conditions from different directions.
- Bilateral symmetry allows motile animals to move straight forward.
- The major evolutionary advantages of bilateral symmetry include cephalization, the formation of a head and tail area and a more directional motion.
Explanation:
Radial symmetry is advantageous for sessile organisms since it enables the uniform distribution of the sensory receptors around the body. In consequence, sessile organisms can react to environmental stimuli from every direction. On the other hand, bilateral symmetry allows motile organisms the arrangement of a specialized nervous system from the anterior end of the organism (i.e., the 'head'). Moreover, another important advantage of bilateral symmetry is the ability to equalize environmental pressures on both sides of the body, thereby enabling a rectilinear motion.
Answer:
TACGTACGTTAC (so the second one)
