3 - Cystic Fibrosis

Question 1

What type of cells are affected by cystic fibrosis?

Answer 1

Epithelial

Question 2

Cystic fibrosis affects the movement of which ions?

Answer 2

Cl-

Question 3

Why are epithelial cells able to move materials into one side and out the other?

Answer 3

They are polarized

Question 4

What are the 4 main organs affected by cystic fibrosis?

Answer 4

1. Lungs
2. Pancreas
3. Sweat glands
4. Male reproductive tract

Question 5

What proportion of Caucasians are carriers for cystic fibrosis?

Answer 5

1 in 25

Question 6

What proportion of Caucasians are diagnosed with cystic fibrosis?

Answer 6

1 in 2500

Question 7

Cystic fibrosis is the result of a mutation on which chromosome?

Answer 7

7

Question 8

In cystic fibrosis, an amino acid is deleted from which gene?

Answer 8

CFTR gene

Question 9

How does the mucociliary escalator protect against infection?

Answer 9

Cilia beat pathogen-trapping mucus into the oropharynx where it can be swallowed

Question 10

Why is someone with cystic fibrosis more likely to suffer repeated lung infections?

Answer 10

Thickened mucus traps pathogens

Question 11

Pancreatic lipase aids in ___ absorption.

Answer 11

Fat

Question 12

Why does cystic fibrosis lead to poor fat absorption?

Answer 12

Thickened mucus blocks pancreatic lipase from reaching the small intestine

Question 13

What is steatorrhea?

Answer 13

Fatty stools

Question 14

How does cystic fibrosis lead to salty sweat?

Answer 14

Due to a dysfunctional CFTR channel, Cl- (and thus Na+) is not reabsorbed by the sweat glands

Question 15

How does cystic fibrosis lead to an early death?

Answer 15

Recurrent lung infections damage the airways

Question 16

What is the current life expectancy for cystic fibrosis?

Answer 16

40 years

Question 17

What percentage of cystic fibrosis patients make their teenage years?

Answer 17

90%

Question 18

Compare type 1 and type 2 thinking.

Answer 18

Type 1: fast, instinctive, usually correct

Type 2: slow, deliberate, often incorrect

Question 19

Two cystic fibrosis carriers have a child. What are the odds that the child will be a carrier?

Answer 19

1 in 2

Question 20

List 6 symptoms of cystic fibrosis.

Answer 20

1. Recurrent chest infections
2. Coughing
3. Wheezing
4. Shortness of breath
5. Fatty stools
6. Failure to thrive

Question 21

What type of epithelium lines the upper respiratory tract?

Answer 21

Pseudostratified columnar ciliated

Question 22

Name the unicellular glands within the respiratory and GI tracts that secrete mucus.

Answer 22

Goblet cells

Question 23

How does physiotherapy help with cystic fibrosis?

Answer 23

Clears mucus from the airways

Question 24

What pharmacological agents are commonly used to combat lung infections in cystic fibrosis?

Answer 24

Antibiotics

Question 25

What is the medical term for swollen fingernails?

Answer 25

Clubbing

Question 26

List 3 types of dietary supplements for cystic fibrosis patients.

Answer 26

1. Pancreatic lipase supplements 2. Vitamins A, D, E, and K 3. Calcium

Question 27

How does cystic fibrosis affect the male reproductive tract?

Answer 27

Absence of the vas deferens means sperm can be made but not ejaculated

Question 28

A newborn with cystic fibrosis will have ___ sodium levels in the sweat.

Answer 28

High

Question 29

Explain how cystic fibrosis causes thick mucus.

Answer 29

``` Defective CFTR channel -> Cl- trapped in cell -> Na+ follows -> Water follows Less water in mucus ```

Question 30

Water follows Na+ across the cell membrane due to what phenomenon?

Answer 30

Osmosis

Question 31

Why would Na+ follow Cl-?

Answer 31

Cations and anions travel together to maintain ELECTRO-NEUTRALITY

Question 32

A patient with cystic fibrosis uses a DNase spray. What is the origin of the target DNA?

Answer 32

White blood cells collecting to fight infection

Question 33

What pharmacological treatment would break down excess DNA?

Answer 33

DNase spray

Question 34

Define hypoxia.

Answer 34

Low oxygen in blood

Question 35

What causes clubbing of the fingernails?

Answer 35

Long-term hypoxia

Question 36

List 4 conditions that could lead to clubbing of the fingernails. (Hint: involve long-term hypoxia.)

Answer 36

1. Lung cancer 2. Sarcoidosis 3. Tuberculosis 4. Tetralogy of Fallot

Question 37

List 4 vitamins whose absorption is hindered in cystic fibrosis patients. (Hint: fat-soluble).

Answer 37

1. A 2. D 3. E 4. K

Question 38

Why are pancreatic secretions trapped in cystic fibrosis?

Answer 38

Thickened mucus sticks them in place

Question 39

Who is unlikely to be a cystic fibrosis carrier?

Answer 39

People of colour

Question 40

What is genetic drift

Answer 40

Change in allele frequency caused by chance (visualize: natural disaster)

Question 41

What are the 5 principles of Hardy-Weinberg equilibrium?

Answer 41

1. No MUTATIONS 2. No MIGRATION 3. No GENETIC DRIFT 4. No NON-RANDOM MATING 5. No NATURAL SELECTION Remember: Marilyn Monroe Gets Naked Nightly

Question 42

Describe 3 principles of treatment for cystic fibrosis.

Answer 42

1. Fight INFECTION (antibiotics) 2. Clear AIRWAYS (physiotherapy, mucus-thinning medication) 3. Ensure proper NUTRITION (rich diet, vitamins)