The answer is true letter a
The macronucleus is the larger elipse-shaped nucleus and takes care of
functions like respiration and digestion. In contrast to this, the
smaller micronucleus is only involved in cell division or reproduction.
- Oxygen cycle is the cycle which maintains the level of oxygen in the atmosphere.
- Oxygen from the atmosphere is used up during combustion, respiration and in the formation of oxides of nitrogen.
- This oxygen is returned to the atmosphere by lithosphere.
- This forms the oxygen cycle in nature.
Hope you could get an idea from here.
Doubt clarification - use comment section.
Nucleotides are the building blocks ofnucleic acids; they are composed of three subunit molecules: anitrogenous base, a five-carbon sugar (ribose or deoxyribose), and at least one phosphate group.
Answer;
A person who sprints for 45 seconds obtains most of his or her energy from muscle glycogen.
Explanation;
Muscle glycogen is the glycogen that is stored in the muscles and liver.
Glycogen is the primary source of energy during exercise, and low glycogen levels decreases the ability to gain strength and muscle. An athlete who sprints for 45 seconds obtains most of his or her energy from the muscle glycogen.