2.8 Gas exchange

Question 1

alveoli

Answer 1

tiny air sacs in the lungs at the end of the bronchioles where gas exchange occurs
adapted by having:
thin moist walls for short diffusion distance
folded walls for larger surface area
capillaries close by to maintain a high concentration gradient

Question 2

bronchi

Answer 2

airways branching from the trachea that lead into the lungs

Question 3

bronchioles

Answer 3

small airways branching from each bronchi in each lung

Question 4

capillaries

Answer 4

thin, narrow blood vessels where the exchange of substances between the blood and tissue occurs

Question 5

diaphragm

Answer 5

muscle that contracts and relaxes to change the volume of the thorax and ultimately the pressure to control inhalation and exhalation

Question 6

intercostal muscles

Answer 6

muscles between the ribs that contract and relax to move the ribcage and change the volume and pressure during inhalation and exhalation

Question 7

pleural membrane

Answer 7

airtight membranes covering the lungs and the thorax to maintain pressure changes and stop the lungs from sticking to the ribcage