Unit 11 - Gas exchange in humans Flashcards
1
Q
Path of air
A
Nose/mouth –> Larynx –> Trachea –> Bronchi –> Bronchioles –> alveoli
2
Q
Gas exchange location
A
Surface of alveoli
3
Q
Gas Exchange in alveoli
A
- Oxygen diffuses from air in alveoli to bloodstream & capillaries
- Carbon dioxide diffuses from capillaries & blood stream into air in alveoli
4
Q
Adaptations of alveoli
A
- Large surface area
- Thin
- Good blood supply
- Good ventilation with air
5
Q
Trachea
A
- Airway connected to the mouth and nose
- Contains rings of cartilage to support it and keep it open
6
Q
Thorax
A
- The chest - between the neck and abdomen
- Changes in volume allow air to push in and out of lungs - caused by contraction and relaxation of diaphragm and intercostal muscles
7
Q
Exhale
A
- Internal intercostal muscles contract, external relax
- Ribcage moves downwards and inwards
- Volume decreases - pressure increases
- Air pushed out of lungs
8
Q
Inspired air
A
21% oxygen, 0.04% carbon dioxide, water vapor
9
Q
Expired air
A
16% oxygen, 4% carbon dioxide, high levels of water vapor
10
Q
Inhale
A
- Internal intercostal muscles relax, external contract
- Ribcage moves upwards and outwards
- Volume increases - pressure decreases
- Air pushed in lungs
11
Q
Reason for gas exchange
A
- Oxygen is used by cells for aerobic respiration
- Carbon dioxide is a waste product and has to be removed
12
Q
Reason for more water vapor in expired air
A
Moisture evaporated from cells of the gas exchange surface
13
Q
Effects of exercise on breathing
A
- More respiration during physical activity to provide energy to muscles
- More Carbon dioxide produced
- Triggers body to increase rate & depth of breathing to expel carbon dioxide + increase oxygen inhale
14
Q
Goblet cells
A
- Produce sticky mucus
- Mucus lines the inside of the trachea
- Inspired pathogens are trapped
15
Q
Ciliated cells
A
- Line the surface of the nose, trachea, bronchi and bronchioles
- Tiny hairs to sweep mucus out of breathing system to the throat to be swallowed
