Review posters 11/05/2016

Question 1

Pulmonary ventilation

Answer 1

Volume of air breathed in and out per minute

= TV x RR

Question 2

Anatomical dead space

Answer 2

Not all the air inhaled reaches the alveoli for gas exchange. This air is unusable and is therefore known as anatomical dead space.

Question 3

Alveolar ventilation

Answer 3

Volume of air exchanged between the alveoli and the atmosphere per minute
= (TV-anatomical dead space) x RR

Question 4

Describe the ventilation and perfusion of the lung

Answer 4

Lung is less ventilated and perfused at the top.

Better ventilated and perfused at the bottom.

Question 5

Alveolar dead space.

Answer 5

When an alveolus is well ventilated but not well perfused.

Question 6

How would you go about increasing pulmonary ventilation?

Answer 6

Increasing TV or RR. Increasing depth of breathing (TV) is the most advantageous due to anatomical dead space.

Question 7

What four factors influence the rate of gas exchange in the alveoli?

Answer 7

The thickness of the alveoli
The surface area of the alveoli
The diffusion co-efficient of oxygen and carbon dioxide
Partial pressure gradient

Question 8

What is the diffusion co-efficient ?

Answer 8

The ability of a gas to dissolve in the membrane. Carbon dioxide has a much higher one that oxygen (20x)

Question 9

Daltons law

Answer 9

The total pressure exerted by a gas is the sum of the partial pressures of each individual gas.

Question 10

What is partial pressure of a gas?

Answer 10

The pressure that one gas in a mixture of gases would exert if it were the only gas present occupying the same volume

Question 11

The equation to work out the partial pressure of oxygen in the alveoli is:

Answer 11

PaO2= PiO2- [PaCO2/0.8]

PaO2= the alveoli partial pressure of oxygen
PiO2= the partial pressure of inspired oxygen
PaCO2= the partial pressure of CO2 in the arteries
0.8= the respiratory exchange ratio

Question 12

Ficks law

Answer 12

The amount of gas that moves across a sheet is proportional to the area but inversely proportional to its thickness.

Question 13

What is the purpose of the membrane?

Answer 13

To form a boundary
Selectively permeable
Maintains difference in ion concentration
Controls entry of nutrients and exit of waste

Question 14

Name the sorts of proteins you would find in the lipid bilayer?

Answer 14

Integral proteins (span the bilayer). These could be ion channels or carrier proteins
Peripheral proteins (sit on the outside of the membrane)
Glycoproteins- sugar attached to proteins on the outside of the membrane

Question 15

Docking mannose receptors

Answer 15

Allow exocytosis

Question 16

Describe the lipid bilayer

Answer 16

Fluid membrane made up of phospholipid molecules.
Each phospholipid molecule has a hydrophillic head and hydrophobic tail.
Cholesterol is present in the membrane and offers stability and fluidity.

Question 17

What types of junctions can you get between cells?

Answer 17

Desmosomes
Gap junctions
Tight junctions

Question 18

Describe the types of junctions you can get between cells

Answer 18

Desmosomes- adhering junctions. Anchor cells together in tissues prone to stretch e.g. skin, cardiac
Tight junctions- lateral borders of epithelial cells joined together.
Gap junctions- communicating junctions that allow movement of charged ions

Question 19

Purpose of membrane carbohydrates

Answer 19

Self identity markers- different cells have different markers.

Question 20

What are the factors important for a particle to be able to diffuse across a membrane

Answer 20

Lipid solubility
Size of the particle
Magnitude of the concentration gradient
Surface area
Diffusion distance

Question 21

Diffusion

Answer 21

Movement of particles from a high concentration to a low concentration (passive process)

Question 22

Osmosis

Answer 22

Net diffusion of water from a high concentration to a low concentration (passive process)

Question 23

Name the two active processes that can transport particles across a membrane

Answer 23

Active transport

Facilitated diffusion

Question 24

Facilitated diffusion

Answer 24

Movement of particles via a carrier/channel protein down their concentration gradient.

Question 25

Active transport

Answer 25

Two types- secondary active transport and primary active transport

Question 26

Primary active transport

Answer 26

Movement of the particle against its concentration gradient using energy derived from ATP

Question 27

Secondary active transport

Answer 27

Ions are used to provide energy to drive a particle against its concentration gradient

Question 28

The two types of secondary active transport

Answer 28

Antiport- ion moves in different direction to particle

Symport-ion moves in the same direction to particle

Question 29

Importance of the sodium pottasium pump

Answer 29

Maintains intracellular concentrations of Na+ and K+
Regulates cell volume by controlling concentration
Provides energy for secondary active transport

Question 30

Osmolarity

Answer 30

The amount of osmotically active substances present in a solution

Question 31

Tonicity

Answer 31

The effect osmolarity has on cell volume

Question 32

Three key things for carrier mediated transport

Answer 32

Specificity
Competition
Saturation