3.1.5- Gas Exchange In Other Organisms Flashcards Preview

Biology AS- Chapter 3.1- Exchange Surfaces And Breathing > 3.1.5- Gas Exchange In Other Organisms > Flashcards

Flashcards in 3.1.5- Gas Exchange In Other Organisms Deck (20):

Explain what counter current flow is.

Where two fluids flow in the opposite direction.


Define 'filaments'.

Slender branches of tissue that make up the gill in fish- often called primary lamellae.


What is the operculum?

A bony flap that covers and protects the gills.


define 'spiracle'.

An external opening or pore in insects that allows air in or out of the tracheae.


What is the 'tracheal fluid'?

The fluid found at the ends of the tracheoles in the tracheal system.


What is the tracheal system?

A system of air filled tubes in insects.


What two things do fish use their gills for?

To absorb oxygen dissolved in the water and release carbon dioxide into the water.


What are the gills covered by?

A bony flap called the operculum.


Explain the structure of a Gill.

Each Gill consists of two rows of v thin filaments attached to a bony arch and their surface is folded into many secondary lamellae.


Explain what the (secondary) lamellae is.

Folds of the filaments in gills that increase the surface area of them. Sometimes called Gill plates.


Why are filaments folded into secondary lamellae?

To provide a larger surface area.


__________ __________ carry deoxygenated blood close to the surface of the secondary lamellae where exchange takes place.

Blood capillaries.


What is the purpose of the countercurrent flow of blood in fish?

Do that the maximum amount of oxygen from the water is absorbed.


Explain how a countercurrent flow is created in fish and the need for this.

blood flows along the Gill arch and out along the filaments to the secondary lamellae and blood then flows through the capillaries in the opposite direction to the flow of water over the lamellae. Needed so the maximum amount of oxygen from the water is taken up.


By what mechanism can bony fish keep water flowing over the gills?

Using a buccal- opercular pump.


Explain the process of ventilation in bony fish.

Floor of buccal cavity moves down, drawing air into it- floor then rises again and water is pushed through the gills. As water is moved from
The buccal cavity, the operculum moves outwards to reduce the pressure in the opercular cavity, helping water to flow through the gills.


In the ventilation of bony fish, the movements of the operculum is coordinated with the movements of what?

The buccal cavity.


Insects have what type of circulatory system?

An open circulatory system.


What supplies air to the respiring tissues in insects?

The tracheal system.


What is the buccal cavity?

The mouth.