Exchange in the mammalian lungs

HideShow resource information
  • Created by: rachel
  • Created on: 10-02-13 12:27
What is ventilation?
Breathing air in and out of the lungs.
1 of 34
What is gaseous exchange?
Diffusion of oxygen and carbon dioxide between air in the alveoli and the blood.
2 of 34
What is respiration?
Chemical processes that occur inside cells to transfer energy from molecules, such as glucose and fat, to ATP; may be anaerobic or aerobic.
3 of 34
Why does ventilation and gaseous exchange occur?
To provide cells with oxygen and remove the carbon dioxide they produce.
4 of 34
Where are ciliated epithelium found in the gaseous exchange system and what is their function?
Trachea, bronchi and bronchioles. Cillia move mucus up the airways.
5 of 34
Where are goblet cells found in the gaseous exchange system and what's their function?
Trachea and bronchi. They secrete mucus.
6 of 34
Where is cartilage found in the gaseous exchange system and what is its function?
Trachea and bronchi. It holds open the airways to allow easy flow of air.
7 of 34
Where is smooth muscle found in the gaseous exchange system and what is its function?
The trachea, bronchi and bronchioles. Smooth muscle contracts to narrow the airways.
8 of 34
Where are elastic fibres found in the gaseous exchange system and what is their function?
They are found in all parts of the system, including alveoli. They strech when breathing in; recoil when breathing out helping to force air out of the lungs.
9 of 34
Where are squamous epithelium cells found in the gaseous exchange system and what is their function?
They are thin to give a short diffusion pathway for gaseous exchange and provide a large surface area.
10 of 34
Where are capillaries found in the gaseous exchange system and what is their function?
They are found in all parts of the system - many around the alveoli. They provide a large surface area for exchange between blood and alveolar airs.
11 of 34
What are alveoli?
Tiny air filled sacs adapted for the efficient exchange of gases by diffusion between the air and blood capillaries.
12 of 34
What are the two main ways that alveoli are adapted for efficiency?
They have a short diffusion distance and a steep concentration gradient.
13 of 34
How come alveoli have a short diffusion distance and what does this allow to happen?
Because the cells lining the alveoli and blood capillaries are thin squamous epithelial cells. This allows easy diffusion of oxygen and carbon dioxide even though there are five cell membranes between the air and the haemoglobin inside red blood cell
14 of 34
How come alveoli have a steep concentration gradient?
Breathing ventilates alveoli maintaining a high concentration of oxygen in alveolar air; blood flows through capillaries in lungs bringing a constant supply of deoxygenated blood. This creates a steep diffusion gradient as there is a large difference
15 of 34
Why is a steep concentration gradient good to have?
It makes diffusion of oxygen from the air into the blood rapid.
16 of 34
what happens to the carbon dioxide and its concentration gradient during ventilation?
The opposite to oxygen and the concentration gradient isn't as steep.
17 of 34
What are the lungs ventilated by?
movements of the diaphragm and ribcage
18 of 34
During inspiration, what happens?
Diaphragm muscles contract & pull the diaphragm down to abdomen. External intercostal muscles contract & raise ribcage. volume of thorax >. Air pressure in lungs <. Air moves from atmosphere into lungs because air pressure in atmosphere is greater.
19 of 34
During expiration, what happens?
Diaphragm (D) muscles relax & contents of abdomen push D ^ into thorax. Ribs fall - gravity. I.C muscles may contract to lower ribcage. Volume of the thorax <. Pressure of air in the lungs is greater than the pressure of atmosphere so air's forced ou
20 of 34
What is the tidal volume and what's the usual reading?
the volume of air that breath in and then breath out during one breath (usually 500cm3)
21 of 34
How can you increase your tidal volume and or vital capacity?
By doing exercise, singing or playing a wind instrument.
22 of 34
What is vital capacity and what's the usual reading?
the volume of air you can force out after taking a deep breath. For young adult males - 4.6dm3. For females - 3.1dm3
23 of 34
Give two measurements of lung function.
Vital capacity and Tidal volume.
24 of 34
What is the total lung volume and what is the usual residual volume of the lungs?
Vital capacity + the volume of air left in the lungs once you breath out forcibly. 1dm3
25 of 34
Whats the total lung volume of a young male?
Between 5 - 6 dm3
26 of 34
What can measurements of lung volumes be made with?
A spirometer
27 of 34
How does a spirometer work?
Pen fixed to lid of device makes trace on paper fixed to revolving drum. As person inhales, lid falls & pen makes downward movement. As person breathes out, lid rises & pen makes upward movement.
28 of 34
How can you find the tidal volume on a spirometer trace?
The difference between peak & trough.
29 of 34
How can you find the vital capacity on a spirometer trace?
By looking at the total volume of air breathed out after taking a deep breath.
30 of 34
How can you calculate the breathing rate from the spirometer trace?
look at the number of peaks / troughs per minute. Example: 6 in 30 seconds = a breathing rate of 12 breaths min-1.
31 of 34
how can you calculate the oxygen consumption from a spirometer trace?
By looking at the gradient of the trace.
32 of 34
What are the features of an efficient gaseous exchange surface?
large surface area, short distance separating blood from the environment (water or air), good blood supply, and a method of moving water or air over the exchange surface
33 of 34
What can a spirometer measure?
TV, VC and a number of breaths per minute.
34 of 34

Other cards in this set

Card 2

Front

What is gaseous exchange?

Back

Diffusion of oxygen and carbon dioxide between air in the alveoli and the blood.

Card 3

Front

What is respiration?

Back

Preview of the front of card 3

Card 4

Front

Why does ventilation and gaseous exchange occur?

Back

Preview of the front of card 4

Card 5

Front

Where are ciliated epithelium found in the gaseous exchange system and what is their function?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »See all Cellular processes and structure resources »