Structure and Function of Fish Gills Quiz

Obtaining O2 from Water vs. Air

• Obtaining O2 from water is more challenging than from air because water contains less O2 and is more viscous, making it harder to extract O2.
• Air contains a higher concentration of O2, making it easier to extract.

Moving Respiratory Medium for Gas Exchange

• Animals move the respiratory medium (air or water) over the respiratory surface (lungs, gills, or tracheae) for gas exchange using mechanisms such as breathing, ventilation, or circulation.

Respiratory Surfaces

• Not mentioned: skin (although skin can be used for gas exchange in some animals, it's not a primary respiratory surface)

Fish Gills

• Fish gills use a countercurrent exchange system for gas exchange.
• Gills create a large surface area for gas exchange to compensate for the low O2 levels in water.
• Blood flow in fish gills is in the opposite direction to water passing over the gills, allowing for efficient O2 and CO2 exchange.
• The function of fish gills is to extract O2 from water and release CO2.

Insect Tracheal System

• The tracheal system in insects is responsible for supplying O2 directly to body cells.
• Larger insects need to ventilate their tracheal system to ensure O2 delivery to their cells.

Counter-Current Exchange

• Counter-current exchange in fish gills allows for the efficient exchange of O2 and CO2 between the water and blood.

Insect Oxygen Supply

• The tracheae are responsible for supplying O2 directly to body cells in insects.

Lungs and Metabolic Rate

• The size and complexity of lungs correlate with an animal's metabolic rate, with higher metabolic rates requiring more efficient gas exchange.

Direct Exchange Limitations

• Direct exchange with the environment is not possible for most cells in multicellular organisms due to the complexity of the body and the need for a specialized gas exchange system.

Purpose of Gills

• The purpose of gills in animals is to extract O2 from water and release CO2.

Circulation and Gas Exchange

• Circulation and gas exchange are closely related in most animals, as the circulatory system transports O2 and CO2 to and from the respiratory surface.

Internal Transport Systems

• Small and thin animals do not require internal transport systems for material exchange because they can rely on diffusion for gas exchange.
• The primary function of internal transport systems in complex animals is to facilitate the exchange of materials, including O2 and CO2, between the environment and the body.

Feathery Fringes

• Feathery fringes in animals (such as gills or tracheae) play a crucial role in survival by increasing the surface area for gas exchange.

Internal Transport Systems Function

• The primary function of internal transport systems in complex animals is to facilitate the exchange of materials, including O2 and CO2, between the environment and the body.