Logistic Growth

Q. _____________ showed that a slow growing animal like elephant could reach enormous population densities in the absence of checks.

1. Darwin
2. Verhulst Pearl
3. Allen
4. Ernst Haeckel

Q. The sigmoid growth curve has four phases.Choose the correct sequence in which it occurs

1. Acceleration- Deceleration-Lag phase Asymptote
2. Asymtote-Acceleration – Deceleration – Lag phase
3. Lag phase – Acceleration – Deceleration – Asymtote
4. Acceleration – Lag phase – Deceleration – Asymtote

Q.

When does the growth rate of a population following the logistic model equals zero? The logistic model is given as
dN/dt = rN (1-N/K)

1. When N/K is exactly one

2. When N nears the carrying capacity of the habitat

3. When N/K equals zero

4. When death rate is greater than birth rate

Q. In logistic growth, as N approaches K the growth rate will .

1. increase
2. decrease
3. not change

Q.

(a) In a pond there were 200 frogs. 40 more were born in the year. Calculate the birth rate of the population.

(b) Population in terms of number is not always a necessary parameter to measure population. Justify with two examples. [3]

Q.

State whether the following statements are true (T) or false (F).

I. Carrying capacity of a population is represented by ‘r’.

II. A population growing in a habitat with limited resources shows initially a lag phase.

III. Logistic growth model is represented by a J- shaped curve.

1. I - T, II - F, III - T
2. I - F, II - F, III - T
3. I - F, II - T, III - F
4. I - T, II - T, III - F

Q. The sigmoid growth curve has four phases.Choose the correct sequence in which it occurs

1. (i) Log phase., (ii) Lag phase., (iii) Stationary phase., (iv) Death phase
2. (i) Stationary phase., (ii) Log phase., (iii) Lag phase., (iv) Death phase
3. (i) Lag phase., (ii) Log phase., (iii) Stationary phase., (iv) Death phase
4. (i) Lag phase., (ii) Stationary phase., (iii) Log phase., (iv) Death phase

Q. The sigmoid growth curve

1. natality balance mortality
2. natality is more than mortality
3. natality is less than mortality
4. natality is zero

Q. When does the growth rate of a population following the logistic model equal zero $?$ The logistic model is given as
$dN/dt=rN(1-N/K)$

Q.

The population of an insect species shows an explosive increase in numbers during rainy season followed by its disappearance at the end of the seasons.This growth shows which type of growth curve?

Q. All population in real world show logistic growth rather than exponential growth. Which of the following describes best why exponential growth is not possible?

1. The resources are unlimited
2. Organisms conserve energy by not reproducing
3. Carrying capacity of the area where population is found, is achieved
4. All of these

Q.

When does the growth rate of a population following the logistic model equals zero? The logistic model is given as
dN/dt = rN (1-N/K)

1. When N/K is exactly one

2. When N nears the carrying capacity of the habitat

3. When N/K equals zero

4. When death rate is greater than birth rate

Q. The changes in two populations of herbivores in a grassy field is shown by graph . What is the reason for these changes?

1. All of the plant populations in this habitat decreased
2. Population B competed more successfully for food than did population A
3. Population A produced more offspring than population B did
4. Population A consumed the members of population B
5. Over time, both populations will have the same average number

Q. In logistic growth, as N approaches K the growth rate will .

1. increase
2. decrease
3. not change

Q.

Give the appropriate biological/ technical term for the following:

The rapid increase in population.

Q. In natural conditions, a population exhibits ___ mode of growth.

Q. In natural conditions, a population exhibits ___ mode of growth.

Q. Very short answer type.
Name the three phases in the sigmoid growth curve.

Q. The graph shows two types of population growth curve. A is exponential and B is logistic.
Which one of the following growth model considered as more realistic one?

1. Exponential growth curve
2. Logistic growth curve
3. Both the growth curves
4. None of the above

Q. All population in real world show logistic growth rather than exponential growth. Which of the following describes best why exponential growth is not possible?

1. The resources are unlimited
2. Organisms conserve energy by not reproducing
3. Carrying capacity of the population is achieved
4. All of these

Q. Refer the table below containing data obtained for a rabbit population over a period of several years.

Year	Number of rabbits
1	4
2	17
3	62
4	245

Which of the following graphs best represents the data on rabbit population size?

1. 
2. 
3. 
4. 
5. 

Q. When does the growth rate of a population following the logistic model equal zero? The logistic model is given as dN/dt= rN(1 − N/K ):

1. When N/K is exactly one
2. When N nears the carrying capacity of the habitat
3. When N/K equals zero
4. When death rate is greater than birth rate

Q. The population of an insect species shows an explosive increase in numbers during rainy season followed by its disappearance at the end of the season. What does this show ?

1. The population of its predators increases enormously
2. S - shaped or sigmoid growth of this insect
3. The food plants mature and die at the end of the rainy season
4. Its population growth curve is of J-type

Q.

When does the growth rate of a population following the logistic model equals zero? The logistic model is given as
dN/dt = rN (1-N/K)

1. When N/K is exactly one

2. When N nears the carrying capacity of the habitat

3. When N/K equals zero

4. When death rate is greater than birth rate