Respiratory system

Question 1

Function of the nasal cavity

Answer 1

Nasal conchae increase surface area, as inhaled air moves through nasal cavity it contacts the mucous and the air is warmed and humidified

Question 2

Trachea has

Answer 2

C-shaped rings of cartilage which hold open the trachea, cilia- hair-like projections that beat rhythmically to move material past the cells, trapping it in mucous to be swallowed

Question 3

Pleural membrane

Answer 3

Thin layers of tissue, one tightly adherent to the lung, second layer tightly adherent to the chest wall, has a pleural space with pleural fluid which reduces friction

Question 4

Bronchi and bronchioles

Answer 4

Trachea branches off into bronchi (one for each lung), each bronchi branches into smaller tubes (bronchioles)

Question 5

Alveoli

Answer 5

Clusters of air sacs bronchioles open into, surrounded by a network of blood capillaries, Oxygen that is breathed in diffuses from the alveoli into the blood, Carbon dioxide diffuses from the blood into the alveoli

Question 6

Ventilation

Answer 6

Process by which air is moved into and out of the lungs

Question 7

Air moves from

Answer 7

High pressure to low pressure

Question 8

Inhalation

Answer 8

Diaphragm contracts making it shorter and flatter decreasing lung air pressure by increasing thoracic volume, external intercostals contract lifting the ribs up and outwards also decreasing the pressure so the air moves into the lungs

Question 9

Exhalation

Answer 9

Internal intercostals pull ribs down and inwards increasing the air pressure by decreasing thoracic volume, diaphragm and external intercostals relax increasing the air pressure, greater air pressure in the lungs mean air moves out

Question 10

Gas exchange

Answer 10

Process where respiratory gases diffuse across a surface, O2 delivered to lungs and body tissues, CO2 moved from the body tissues into the lungs

Question 11

Why we need gas exchange

Answer 11

Body relies on being able to get oxygen so cellular respiration can occur, body needs to remove carbon dioxide as it quickly becomes toxic to body cells

Question 12

Features that allow for effective gas exchange (5)

Answer 12

Large surface area, large blood supply, thin structures, moist surfaces, maintenance of the concentration gradient

Question 13

Why is a large surface area needed for effective gas exchange

Answer 13

Large surface areas increase rate of diffusion, lungs have large surface area due to the many millions of alveolus, shape of alveoli increases surface area

Question 14

Why is a large blood supply needed for effective gas exchange

Answer 14

Ensures there is a constant supply of CO2 so it can be exhaled, provides blood for the oxygen into the alveoli to move into

Question 15

Why are thin structures needed for effective gas exchange

Answer 15

Alveoli wall and capillary wall are each one cell thick allowing for quick diffusion as gas molecules have less of a distance to travel

Question 16

Why are moist surfaces needed for effective gas exchange

Answer 16

Respiratory gases need to be dissolved in fluid so they can diffuse, moist surfaces are achieved by the humidified air you breathe in and the positioning of the lungs deep in the body preventing fluid from evaporation

Question 17

Why is the maintenance of a concentration gradient needed for effective gas exchange

Answer 17

Must be a concentration gradient for diffusion to occur, must have high concentration of oxygen and low concentration of CO2 in the alveoli, concentration gradient achieved by CO2 being breathed out, oxygen being breathed in

Question 18

Emphysema

Answer 18

Incurable lung disease caused by damage to the lung tissue involved in gas exchange, inhaled irritants damage the alveoli- cigarette smoke, working conditions, pollution, damaged tissue in the alveoli break down which reduces the surface area on which gas exchange can occur and reduces elasticity of the lung tissue meaning the lungs are constantly inflated

Question 19

Asthma

Answer 19

Can be due to an allergic response, bronchioles become more inflamed and produce more mucous, muscles around the bronchioles go into spasm and contract narrowing the air passages, bronchodilators (Ventolin) relax the muscles in the bronchioles

Question 20

Mesothelioma

Answer 20

Cancer affecting the mesothelial cells, affects the pleural membranes as it puts pressure on the lung killing the alveoli, caused by exposure to asbestos and only becomes apparent years after exposure

Question 21

Mesothelioma symptoms

Answer 21

Shortness of breath, chest pain, loss of appetite/weight loss, persistent cough

Question 22

Asbestos

Answer 22

Fibrous dust that can be breathed in and damage cells