Module 3: Exchange surfaces and breathing Flashcards
What is gas exchange in insects?
The process of exchanging oxygen and carbon dioxide between the insect’s body and the environment.
How do insects exchange gases?
Through a system of tiny tubes called tracheae. Oxygen enters the tracheae and diffuses into the insect’s body, while CO2 produced by cellular respiration diffuses out of the insect’s body and into the tracheae.
What is the tracheal system in insects?
A network of tiny tubes that run throughout the insect’s body, providing a direct connection to the environment.
How does the structure of the tracheal system support gas exchange in insects?
With its small diameter and large surface area, enables efficient gas exchange. The tracheae are lined with a permeable cuticle that allows gases to diffuse into and out of the insect’s body.
What role does the spiracles play in gas exchange in insects?
Spiracles are the openings to the tracheal system on the surface of an insect’s body. The spiracles can open and close, allowing the insect to regulate the flow of air into the tracheal system. This enables the insect to control the rate of gas exchange and maintain the balance of oxygen and carbon dioxide in its body.
Most insects are land organisms with a tough exoskeleton. Insects have an exoskeleton, which helps to prevent the insects from losing water from their bodies, as well as protecting them from their environment.
Exoskeletons are too thick for gas exchange. Because of their structure, exoskeletons are usually too thick to allow for simple diffusion to occur for gas exchanges.
Gas exchanges in insects occur via the tracheal system. Gas exchange occurs via a special organ system known as the tracheal system. It is a very simple respiratory system found in many insects.
Mechanical ventilation is used by some active insects. Occasionally, ventilation of active insect’s respiratory systems can happen via mechanical ventilation (pumping the abdomen) or air reserves, sometimes both simultaneously.
There are multiple ways of diffusing gases. Diffusion is used in the trachea, whereas mass transport is used as a result of muscle contraction, and volume changes in the tracheoles.
Spiracles – tiny holes able to let air enter the body and prevent water loss. They are controlled by specialised muscles to be opened or closed. Spiracles are used to pass air to the trachea.
Trachea – a tube lined with chitin, which branches into smaller tubes known as tracheoles.
Tracheoles – they deliver oxygen to the cells and tissues of the insect.
Chitin – impermeable rings which work to stop structures collapsing. As they are impermeable, it stops diffusion.
Lactic acid – oxygen dissolves into this fluid, where it reaches individual cells to start simple diffusion. The carbon dioxide from this process gets released into the environment through the spiracles.
