The answer is carbon dioxide. so its true
The respiratory system consists of all the organs involved in breathing. These include the nose, pharynx, larynx, trachea, bronchi and lungs. ... The nose, pharynx, larynx, trachea and bronchi all work like a system of pipes through which the air is funnelled down into our lungs.
Many scientists never wear a lab coat at all. Some work in fields that don't require lab work and do their work behind a computer. Some use their science degrees to teach or write about science. Some work as consultants for companies, or as editors for scientific journals.
Answer:
Any factor in the environment that does not depend on the number of members in a population.
Explanation:
Density independent limiting factors also cause population sizes to increase. For example, the water from a flash flood increases the growth of vegetation, thereby providing more food for primary consumers in the ecosystem.