Chapter 4: Exchange surfaces

Question 1

What are the properties of a good exchange surface?

Answer 1

Large surface area, thin for maximized diffusion, must have a diffusion gradient, not dry

Question 2

How does oxygen and CO2 diffuse into lungs?

Answer 2

A blood capillary is very close to an alveoli and these both have 1 cell thick walls

Question 3

What group of muscles move the lungs?

Answer 3

The diaphragm

Question 4

How are epithelial tissue in the airways adapted?

Answer 4

Tubes leading down to the lungs are lined with this tissue and it is adapted to remove particles from the air before it reaches the lungs

Question 5

Name the two type of cells that make up epithelial tissue?

Answer 5

Ciliated cells and goblet cells

Question 6

Cilium contains what to allow it to slide?

Answer 6

Microtubules, makes it able to bend

Question 7

What do goblet cells secrete?

Answer 7

Mucus

Question 8

Mucus contains what?

Answer 8

Glycoproteins, makes it slimy and sticky

Question 9

How does mucus help the epithelium?

Answer 9

Prevents it from drying out and traps particles before reaching alveoli

Question 10

Where do you find smooth muscle in the lungs?

Answer 10

Trachea, bronchi and bronchioles, it is an involuntary muscle so it contracts steadily on its own

Question 11

What tissue is not found in the bronchioles?

Answer 11

Cartilage

Question 12

How do elastic fibers help the alveoli?

Answer 12

During breathing in, the alveoli expand stretching the elastic fibers. during breathing out the fibers recoil helping decrease the volume

Question 13

When breathing what happens to the lungs?

Answer 13

Pressure decreases as volume increases. External intercostal muscles contract to move rib cage up and out. Diaphragm contracts to bring it lower, to increase volume =

Question 14

What happens to your lungs when breathing out?

Answer 14

Elastic fibers are stretched, diaphragm and intercostal muscles relax. Pressure increases

Question 15

What does vital capacity mean?

Answer 15

Greatest volume of air you can breath in and out of your lungs in one breath

Question 16

Tidal volume?

Answer 16

Normal volume of air breathed in and out at once

Question 17

Inspiratory reserve volume definition?

Answer 17

The extra air you breath in after taking a deep breath

Question 18

Expiratory reserve volume definition?

Answer 18

Extra air breathed out

Question 19

Equation for surface area of a sphere?

Answer 19

4πr squared

Question 20

Equation for the volume of a sphere?

Answer 20

4/3πr cubed

Question 21

Process of breathing out?

Answer 21

External intercostal muscles relax and the rib cage moves down, diaphragm relaxes making pressure increase and volume decrease, air moves out down the pressure gradient

Question 22

Process of forced breathing out?

Answer 22

Contraction of internal intercostal muscles moving rib cage further down, volume decrease and pressure increase in the thorax. Abdominal muscles contract and raise the diaphragm further upwards

Question 23

Alveoli adaptations?

Answer 23

Very close to capillaries to maximise gas exchange into the blood, 1 cell thick walls for shorter diffusion distance, lots of air spaces for more oxygen to fit, contain elastic fibres

Question 24

Where is the cartilage in the lungs?

Answer 24

Supports the walls of the trachea and bronchi

Question 25

What measures an individuals lung capacity?

Answer 25

Spirometer

Question 26

Describe how a spirometer works?

Answer 26

Person breathes in and out of a chamber. Inside the chamber there is water making it float up and down when breathing. Breath in volume decreases and vice versa. The chamber has a pen attached to a kymograph to record the volumes

Question 27

what absorbs the CO2 in a spirometer?

Answer 27

Soda Lime

Question 28

Precautions to take when using a spirometer?

Answer 28

Ensure you have a healthy patient, sterilise the mouthpiece and use a nose clip to prevent unwanted air leaving