LO2: Respiratory System

Question 1

Describe inspiration and expiration.

Answer 1

Inspiration
- Intercostal muscles contract pulling ribs upwards and out.
- Diaphragm muscles contract and the diaphragm move downwards and in, flattening.
-Volume of lungs increases and pressure decreases below atmospheric pressure and air rushes into lungs

Expiration
- Intercostal muscles relax ribs downwards and in.
- Diaphragm muscles relax and the diaphragm moves upwards and out, back to its original dome shape.
-Volume of lungs decreases and pressure increases above atmospheric pressure and air rushes out of lungs.

Question 2

Role of the pleural membranes and diaphragm

Answer 2

Pleural membranes
- Two thin layers of tissue that has fluid in between.
- Protects and cushions lungs and fluid allow tissue layers to slide against one another

Diaphragm
- Muscles contract and relax to flatten or return back to dome shape
- Increases and decreases volume of chest cavity to allow air to be forced out or rush in.

Question 3

Describe how alveoli are adapted for gas exchange.

Answer 3

• Large surface surface area and many alveoli present increases rate of diffusion.
• One cell thick provide short diffusion pathway.
• Moist walls allow gases to dissolve in moisture to easily diffuse across alveoli.
• Permeable walls
• Large network of capillaries ensure oxygen rich blood is taken away from lungs.

Question 4

Describe gas exchange

Answer 4

• Oxygen dissolved in fluid layer of alveoli diffuses down concentration gradient across lining of alveoli and thin, permeable walls of capillary to erythrocytes.
  -Oxygen binds to haemoglobin of erythrocytes.
• Low conc. of CO2 in alveoli allows CO2 to diffuse out of blood plasma in capillaries and into alveoli, down its diffusion gradient.

Question 5

What is cellular respiration? What is the role of ATP and

Answer 5

Process by which organisms combine oxygen with glucose releasing energy for bodily functions whilst discarding of waste products - CO2 and water.
- Energy stored as ATP which can be broken down into ADP and a phosphate group, releasing energy need by cells.

Question 6

What are the two types of respiration?

Answer 6

Aerobic respiration:
Glucose + Oxygen = Carbon + Water + 38ATP molecules

Anaerobic respiration:
Glucose = Lactic acid + 2ATP molecules

Question 7

What are the 3 respiratory malfunctions?

Answer 7

Asthma: Causes occasional breathing difficulties. Triggers cause inflammation and narrowing of bronchi. Mucus produced more and individual wheezes experience tight chest and coughing.

Emphysema: Part of group of respiratory illnesses (COPD). Caused mainly by long term smoking which overtime paralyses cilia (tiny hair-like structures that clean lungs and airway). Chemicals in smoke eventually kill cilia and leads to a build up of mucus which traps pathogens in lungs, increasing infections. Chemicals in smoke also damage walls of alveoli.

Cystic fibrosis: Inherited condition caused by a defective gene on each pair of chromosomes. Produces faulty protein that moves water & salt in and out of cells. CF patients have unusually thick and sticky mucus which blocks bronchioles and prevents movement of respiratory gases in and out of lungs

Question 8

Monitoring, treatment, lifestyle changes and care needs for respiratory malfunctions.

Answer 8

Monitoring:
- Spirometry (Test measures breathing capability of lungs through volume of air expired).
- Peak flow (Measures rate of exhalation and rate of flow = how much resistance there is to airflow).

Treatments
- Preventative inhaler (used regularly and has corticosteroids that reduce swelling and inflammation)
- Reliever inhaler (relaxes muscles for immediate relief of symptoms)

• Nebulisers help drugs get deeper
• Oxygen therapy (device that contains extra oxygen connected to a tube or mask)
  -Surgery that reduces muscle surrounding airway, opening up airway.

Lifestyle changes:
- identifying triggers and avoiding
-stopping smoking

Care needs:
- carrying inhaler
- prescribed medication
- oxygen therapy