Gaseous exchange

Question 1

What are the properties for rapid diffusion?

Answer 1

Large surface area
Thin walls of alveoli and capillaries
Numerous capillaries around the alveoli
Steep concentration gradient

Question 2

What properties do lungs have for rapid diffusion?

Answer 2

Thin alveoli
Lots of alveoli increasing surface area
Steep concentration gradient due to good blood supply and ventilation of the lungs

Question 3

What’s ficks law?

Answer 3

Rate of diffusion = SA x Dif in Conc/ thickness

Question 4

What’s the fluid mosaic model made of?

Answer 4

glycoprotein, glycolipid, cholesterol, proteins, phospholipid bilayer

Question 5

Describe the phospholipid bilayer?

Answer 5

Hydrophilic phosphate group and hydrophobic fatty acids (2) - prevents ions into the membrane reason for channel and carrier proteins

Question 6

Describe diffusion

Answer 6

Net movement of particles from an area of high concentration to an area of low concentration
Passive

Question 7

Describe osmosis

Answer 7

Net movement of water molecules from an area of high concentration to an area of low concentration
passive

Question 8

Describe facilitated diffusion

Answer 8

Particles are too large so channel proteins are used or carrier proteins
Passive

Question 9

Describe channel proteins

Answer 9

Form pores in the membrane to allow charged particles through through

Question 10

Describe carrier proteins

Answer 10

Bind to the large molcules to change their shape and releases the substance the other side

Question 11

Describe exocytosis

Answer 11

Vesicle from Golgi fuses with the membrane and releases substance

Question 12

Describe endocytosis

Answer 12

Membrane surrounds the substance and it pinches off to form a vesicle with the substance

Question 13

How does sticky mucus increase lung infection chances?

Answer 13

Pathogens get stuck in mucus, its normally moved by cilia to be coughed up or swallowed, mucus production continues, layers of musus lowers o2 levels due to slow diffusion, bacteria thrives in anaerobic conditions

Question 14

How does mucus affect gas exchange

Answer 14

Blocks narrow airways preventing movement of air to alveoli it allows air to when when breathing in but not breathing out so theres over iflation of lung tissue causing loss of elasticity
Not enough o2 to muscle cells

Question 15

Whats the role of mucus in the lungs?

Answer 15

Lung allows rapid gas exchange between atmosphere and blood
Air drawn into lungs via trachea due to low pressure created by increase in volume of thorax as ribs move up and diaphragm moves down
oxygen diffuses out of alveoli across endothelium and into blood
CO2 diffuses into alveoli from blood and breathed out