Lec 3 - Determining Growth Parameters

Question 1

Give the 2 ways in which Ks and umax can be determined

Answer 1

1) assume umax = Dc Ks = s when D = 0.5 umax 2)) plot 1/u against 1/s y intercept = 1/umax x intercept = -1/Ks

Question 2

What occurs when Ks is significant compared to Sr in terms of biomass?

Answer 2

When Ks is significant, biomass is not constant biomass is constant when Ks << Sr graph = x against D

Question 3

Draw the graph that shows what happens when Ks is significant or not compared to Sr

Answer 3

Question 4

What is the eqn relating Y and q?

Answer 4

q = u / Y

Question 5

When Y is constant, the plot of q against u / D should give a straight line through where? What happens when the line doesnt pass through where it should?

Draw this graph

Answer 5

the origin no growth is occurring but the substrate is still being consumed

Question 6

What is the ME used for?

Answer 6

• turnover of macromolecules - maintenance of ion gradients - motion eg flagella movements

Question 7

q actual = q ____ + q _____

Answer 7

growth

maintenance

Question 8

In terms of maintenance energy, draw the graph of x against D

Answer 8

graph 4 represents that at lower Ds, the proportion of energy dedicated to ME rather than growth becomes greater “qm causes deviation from ideal situation at low D and C-limiting conditions”

Question 9

what is Yg ?

Answer 9

true growth yield growth

yield that is corrected for maintenance losses

Question 10

When plotting 1/Y against 1/D what does the Y intercept and the gradient represent? What is the eqn that relates these values?

Answer 10

y intercept = 1/Yg gradient = qm 1/Y = 1/Yg + qm . 1/u

Question 11

Draw the graph of 1/Y against 1/D

Answer 11