Bacteria Nutrition, Growth And Multiplication Curve

Question 1

What is a ‘balanced growth’ for bacteria/microorganisms??

Answer 1

This is an increase in the biomass of the microorganism which is accompanied by a corresponding increase of all measurable characteristic of the population(RNA, DNA, intracellular water).

Question 2

Growth curve is a tool used for both eukaryotic and prokaryotic cell.
True/false

Answer 2

True

Question 3

What is growth curve?

Answer 3

It is the graphical representation of changes that take place within a population overtime.

Question 4

What are the phases in a growth curve?

Answer 4

Lag
Log/exponential
Stationary
Death phase.

Question 5

What is the lag phase??

Answer 5

Tis the period following the introduction of microorganisms into a fresh batch culture medium where there is neither increase in cell number nor decrease in cell mass.

Question 6

In lag phase, the length of time is directly related to the duration of the preceding stationery phase.
True/false.

Answer 6

True.

Question 7

What is ‘log phase/exponential phase’?

Answer 7

Tis the phase at the growth curve whereby the microbial population is growing at a maximum constant rate, dividing and doubling at regular intervals.

Question 8

In the log phase, cells divide fast depending on what?

Answer 8

Growth medium,
Microbial cell,
Environmental conditions.

Question 9

Why does microbial population hardly maintain high rate of population growth for a long time?

Answer 9

Because the log phase has a limited duration

Question 10

Two factors that limit the growth of bacteria are?

Answer 10

1.Exhaustion of viable nutrients,
2.Accumulation of toxic products from metab.

Question 11

What is ‘stationary phase’

Answer 11

Is the phase of microbial growth where population growth ceases and the growth curve levels goes off.

Question 12

At the transition btw the log and stationary phase, the various cellular components are synthesised at equal rates.
True/ false

Answer 12

False.

Question 13

Cells at the stationary phase are smaller than cells at the log phase.
True/false

Answer 13

True.

Question 14

Death of bacteria cells is as a result of which factors?

Answer 14

1. Depletion of cellular reserve of energy.
2. The microorganism e.g enterobacteria die more slowly.
3. The environment.

Question 15

Name the 3 major functions carried out by microbial cells

Answer 15

Mechanical function.
Transport fxn.
Chemical fxn.