Gas Exchange In Single-celled Organisms And Insects Flashcards
What type of SAV do single-celles organisms have?
They have a large surface area to volume ratio.
Why do single celled organisms have large surface area to volume ratio?
Because they are small.
How do oxygen and carbon dioxide move across the body surface?
By simple diffusion across the body-surface which is covered only by cell-surface membrane and.
Does the cell wall act as a barrier to the diffusion of gases?
No
Do insects have mechanisms to conserve water?
Yes
What two things do insects need to balance?
Water conservation and gas exchange.
Why does the increase in surface area for gas exchange conflict with conserving water?
Water will evaporate from it which will cause what a loss.
What is the name of the internal network of tubes in insects for gas exchange?
Tracheae
What are the tracheae supported by?
Strengthened rings to prevent them from collapsing.
What did the tracheae divide into?
Smaller dead-end tubes called tracheoles .
Where do the tracheoles extend throughout?
They extend throughout the body tissue of the insect.
What is brought directly to the respiring tissues?
Atmospheric air with oxygen.
Is there a short diffusion pathway along diffusion pathway from a tracheole to any body cell?
There is a short diffusion pathway.
What are the three ways in which respiratory gases move in and out of the tracheal system?
Along a diffusion gradient;
Mass transport;
The end of the tracheoles are filled with water
What is used up when cells respire?
Oxygen
