pack 7- gas exchange and the effects of CF

Question 1

ficks law

Answer 1

rate of diffusion is directly proportional to surface area and concentration difference
rate of diffusion is inversely proportional to thickness of surface

Question 2

role of mucus in the lungs

Answer 2

trap dirt, dust and microorganisms. then moved by cilia to back of throat to be swallowed.

Question 3

adaptations of mammalian lung and how they help

Answer 3

many alveoli- large surface area
alveoli thin- short diffusion distance
capillaries thin- short diffusion distance
ventilation of alveoli- steep conc gradient
blood flow in capillaries- steep conc gradient

Question 4

why do people with CF have lung infections

Answer 4

mucus build up
anaerobic bacteria builds up due to lack of 02 causing lung infection
white blood cells try to fight- break down release DNA mucus stickier=repeated infection

Question 5

effect f CF on gas exchange

Answer 5

mucus block airways
reduce number of alveoli = reduce surface area
reduce conc gradient = reduced gas exchange
overinflation of alveoli- damage elasticity of lungs

Question 6

effect of CF on digestion and absorption

Answer 6

mucus block pancreatic duct
digestive enzymes cant leave
low con of enzymes = less efficient digestion
less absorbed into blood
lack of glucose for respiration- lack energy in cells- tiredness.

Question 7

effect of CF on pancreas function

Answer 7

mucus block pancreatic duct
pancreatic enzyme trapped behind mucus
produce cysts- hard fibrous
cells producing insulin damage
result in diabetes

Question 8

CF effect on male reproductive system

Answer 8

mucus block sperm duct- vas deferens
may lack tubes
decrease chance of sperm fertilising an egg- sperm cannot leave testes
reduce pregnancy

Question 9

CF effect on femlae reproductive system

Answer 9

mucus plug block cervix
stop sperm depositing in vagina
sperm cant reach egg
reduce pregnancy and fertiliastion