Answer: 2. Each subunit represents a separate polypeptide chain, while one polypeptide chain may contain several domains.
Explanation: Each subunit constitutes of one polypeptide chain. A polypeptide chain has one particular gene coding for it. thus it simply implies that a protein must have one gene for each subunit.
Many proteins is made up of different protein domains. A particular domain may appear in a variety of different proteins.
domains are stable on there own, they can be exchanged via genetic engineering between one protein and another.
Answer:
Many scientists favor the RNA world hypothesis, in which RNA, not DNA, was the first genetic molecule of life on Earth. Other ideas include the pre-RNA world hypothesis and the metabolism-first hypothesis. Organic compounds could have been delivered to early Earth by meteorites and other celestial objects
Answer:
b. active transport
Explanation:
Active transport -
It is the movement of the molecules across the membrane via a region of lower concentration towards the region of higher concentration , and in some cases , the flow is independent of the concentration .Its is known as active transport .
This process needs some amount of energy in the form of cellular energy .
Hence , the correct term for the given statement is active transport .
Answer:
The pulmonary artery carries oxygenated blood from the right ventricle to the lungs. The blood here passes through capillaries adjacent to alveolar and becomes oxygenated as part of the process of respiration. In contrast to the pulmonary arteries, the bronchial arteries supply nutrition to the lungs themselves.
Explanation:
Answer:
According to plate tectonics theory, Earth's outer shell is divided into multiple plates that slowly glide over the mantle. This slowly changes Earth's surface over time by merging, or separating, continents.