2.3 adaptations for transport

Question 1

5 adaptations for transport

Answer 1

ALL
-pump
-valves
-suitable transport medium
SOME
-Vessels
-respiratory pigment

Question 2

Oxygen dissociation

Answer 2

The process of oxygen binding to haemoglobin in the lungs and releasing in respiring tissue

Question 3

Affinity for oxygen

Answer 3

The attraction between haemoglobin and oxygen.
Haemoglobin can alter its affinity for loading and unloading oxygen.

Question 4

Outline the structure of Haemoglobin

Answer 4

-Quartinary form
-globular protein
-4 ham groups each with own fe2+

Question 5

Define and outline the process of co-operative binding

Answer 5

-The increasing ease at which haemoglobin binds to its second and third oxygen molecule.
-O2 binds to iron, altering the shape, making it easier for the second to join…
- Allows haemoglobin to load o2 very rapidly in the lungs.
-Large increase in partial pressure to bind 4th O2 molecule

Question 6

What does cooperative binding do to the graph and why?

Answer 6

when exposed to increasing partial pressure of oxygen, a sigmoid curve is present rather than linear.
Low partial pressure = harder for haemoglobin to load o2

Question 7

Outline the stages of the sigmoid graph

Answer 7

-Oxygen affinity is at its highest in the alveoli… high partial pressure of o2 in lungs.
-As partial pressure decreases by a small amount, saturation of oxygen decreases by a large amount, creating a steep downwards gradient.
-low affinity + o2. is released to meet demands of respiring cells.
-O2 dissociates

Question 8

describe what would happen if the relationship between partial pressure and saturation were Linear.

Answer 8

–At higher pressure, O2 affinity would be too low and o2 would be released before reaching respiring tissue.
- lower partial pressure, o2 affinity gulf be too hight and not released to respiring tissue.

Question 9

Advantages of foetal haemoglobin

Answer 9

-higher o2 affinity
-higher saturation of o2 at any partial pressure
-o2 absorbed form mothers placenta ataxy partial pressure
CURVE MOVES TO LEFT

Question 10

Describe the curve of animals at high altitudes

Answer 10

Furthest to the left.
-high o2 saturation limmited o2 supply means a higher affinity is needed to become saturated-more o2 is loaded into the lungs .

Question 11

Affects of CO2

Answer 11

• CO2 increases the amount of carbonic acid produced, increasing ph
• haemoglobin is less saturated with o2 and more saturated with H+ ions.
• lower affinity
  -MOVES TO RIGHT

Question 12

Define the Bohr affect

Answer 12

Movement of the curve to the right , at any partial pressure of o2 because at any given moment there is a lower affinity for oxygen.

Question 13

Outline the stages of reactions in the red blood cell

Answer 13

• Carbonic anhydrase catalyses the reaction of CO2 and H2O
  -Carbonic acid is made
  -HCO3 - dissociates out of cell
  -Chloride shift to maintain electrochemical neutrality.
  -H+ ions cause oxyhemoglobin to dissociate into oxygen and haemoglobin.
  -H+ combines with haemoglobin to make Haemoglobic acid
• Oxygen diffuses out of cell into tissues .

Question 14

Vessels Vs Tracheids

Answer 14

Vessels- occur only in angiosperms.Water conducting hollow tubes tubes, cells are fused end to end with lignified walls.
Tracheids- all plants, spindle shaped water conducting tubes, less efficient.

Question 15

State cohesion-tension theory

Answer 15

The mechanism where water moves up the xylem . The cohesive and adhesive nature of the polar water creating tension along the xylem.

Question 16

Outline the method of ringing experiments

Answer 16

-investigate translocation in plants.
-Rings of bark removed from woody stem.
-removing the phloem
-high conc of sucrose above and low below.
-showing that the phleom transports sucrose

Question 17

CONVERTING MM TO MICROMETER

Answer 17

mm x 1000 = micrometer

Question 18

CONVERTING MM TO NANO METERS

Answer 18

mm x1000000 = nanometer

Question 19

outline the method of using aphids

Answer 19

aphids Stylet injects into phloem and extracts sucrose.
- stylet remains in phloem and sucrose is forced out and analysed.

Question 20

Outline the process of fluid moving out of capillaries at the arteriole end

Answer 20

1- High hydrostatic pressure from heart contractions forces fluid out into cells
2- Plasma contains plasma proteins which lower the water potential, water moves back into capillaries by osmosis.
3- hydro>osmosis so water and solutes forced out of capillaries

Question 21

-Why is hydrostatic pressure lower at the Venus end of the capillaries?

Answer 21

• Loss of tissue fluid and increase in cross sectional area
• increased friction resists flow

Question 22

Outline the process of water and solutes moving back into the capillaries at the venus end…

Answer 22

• plasma proteins in blood are more concentrated, so water moves into cell by osmosis
  -Tissue fluid picks up co2 and waste product

Question 23

Role of the Lymph capillary

Answer 23

hydrostatic greater than osmosis, so more fluid has been forced out than reabsorbed, lymph vessel reabsorbs and transports back to vein.