Tag: population ecology

Questions Related to population ecology

If in a population showing sigmoid growth curve the value of K - N/K is 0.95, then what is true for this population.

zoology human population population ecology population size population and how it changes

  1. The carrying capacity has been nearly realized.

  2. The carrying capacity has not been substantially realized and it can accommodate many more organisms.

  3. The carrying capacity is only 50% realized.

  4. Data is insufficient to comment anything.

Show answer
Correct Option: B
Explanation:

In the given example, K represents carrying capacity or the maximum capacity that can exist and N represents the actual population present at a particular time. If in a population showing sigmoid growth curve the value of K - N/K is 0.95, then the carrying capacity of this population has not been substantially realized and it can accommodate more organisms. This population has maximum growth rate because it shows that environment can sustain more population.

Thus, the correct answer is 'The carrying capacity has not been substantially realized and it can accommodate many more organisms.'

Carrying capacity for a population is estimated at 500 the population size is currently 400 and max=0.01. What is dN/dt?

zoology human population population ecology population size population and how it changes

  1. 0.01

  2. 0.8

  3. 8

  4. 50

Show answer
Correct Option: B
Explanation:
The logistic population growth model is represented by :
dN/dt = rN (K-N/ K)
Here, N = Population density at time t = 400
r = Intrinsic rate of natural increase = 0.01
K = Carrying capacity = 500
So, dN/dt can be given by, 
dN/ dt = 0.01 × 400 × (100/500)
dN/ dt = 0.8
So, the correct option is '0.8'

According to the latest census the most densely populated country in world is

zoology human population population ecology population size population and how it changes

  1. Pakistan

  2. India

  3. Japan

  4. Bangladesh

Show answer
Correct Option: D
Explanation:

In 2013 the population of Bangladesh was estimated at 160 million. About 89% of Bangladeshis are Muslims, followed by Hindus (8%), Buddhists (1%) and Christians (0.5%). Bangladesh has the highest population density in the world, excluding a handful of city-states and small countries with populations under 10m, such as Malta and Hong Kong.

So, the correct answer is option D.

The best way to reduce the population of undesirable species is

zoology human population population ecology population size population and how it changes

  1. Reduce the carrying capacity of the environment for that species

  2. Elimination of females

  3. Elimination of the young generation

  4. None of the above

Show answer
Correct Option: A
Explanation:

Carrying capacity is the maximum population size of a species that an ecosystem can support indefinitely. When carrying capacity is reached, a population can survive on the resources available without depleting the overall availability of the resources. When a population is below the carrying capacity, the individuals have access to more than enough resources to survive. When a population grows and begins to reach the carrying capacity, the population begins using resources at an equal rate to which the resources are created. This often creates competition between individuals for the available resources. As a result, some individuals will die when they cannot get enough resources and others will not reproduce because they do not have the resources to support offspring. Environmental resistance leads to the establishment of a carrying capacity.

Indian state having highest population density is

zoology human population population ecology population size population and how it changes

  1. Kerala

  2. West Bengal

  3. Maharashtra

  4. Punjab

Show answer
Correct Option: B
Explanation:

West Bengal is the state with highest population density in India. According to the 2001 census, West Bengal has a population density of 903. Total population of West Bengal (as per 2001 census) is 8,01,76,197 and its area is 88,752 sq km. 

Which one has mainly controlled human population density?

zoology human population population ecology population size population and how it changes

  1. Industry

  2. Natural resources

  3. Climate

  4. Communication

Show answer
Correct Option: B
Explanation:
Natural resources are resources that people can use which comes from nature. People do not make natural resources but obtain from the nature such as air, water, wood, oil, wind energy, iron, and coal. Higher the population, more the demand on resources. Thus, the growth of human population will result in the decrease of natural resources. More the number of human will demand more of land, water, etc. In other words, availability of natural resources is a limiting factor of increase of human population. They are inversely proportional.
So, the correct answer is option B.

The density of population can be calculated

zoology human population population ecology population size population and how it changes

  1. $D = \displaystyle\frac{N}{S} \left(\displaystyle\frac{Number}{Space}\right) $

  2. $D = \displaystyle\frac{S}{N} \left(\displaystyle\frac{Space}{Number}\right) $

  3. $D = \displaystyle\frac{S}{W} \left(\displaystyle\frac{Size}{Weight}\right) $

  4. None of the above

Show answer
Correct Option: A
Explanation:

The formula for finding the population density is: 

PD or population density = number of organisms/area (space). In the formula, PD stands for population density; N stands for the number of organisms; A stands for the area. To get the PD, divide the number of organisms by the area (space).
So, the correct answer is option A.

Which of the following factors affect human life with increasing to population density?

zoology human population population ecology population size population and how it changes

  1. Availability of food housing and health facilities

  2. Urbanization

  3. Education

  4. None of the above

Show answer
Correct Option: A
Explanation:

Human population is directly affected by - 

(1) Increases in food production and distribution, 
(2) Improvement in public health (water and sanitation)
(3) Medical technology (vaccines and antibiotics), along with gains in education and standards of living within many developing nations.
So, the correct answer is option A.

If population of a species is transferred to more suitable environment, then it will show 

zoology human population population ecology population size population and how it changes

  1. Protection against enemies

  2. More individuals would survive

  3. Rate of reproduction increases

  4. Unlimitied food would be available

Show answer
Correct Option: A
Explanation:

If the population of a species is transferred to the more suitable environment, then it will show  protection against enemies. Populations are groups of individuals belonging to the same species that live in the same region at the same time. Population density is a measure of the number of organisms that make up a population in a defined area. In the suitable environment, the species of the population becomes more strong to fight with enemies and protect themselves.

So, the correct answer is option A.

What was the population density of India according to $2001?$

zoology human population population ecology population size population and how it changes

  1. $124$ persons $/km^2$

  2. $224$ persons $/km^2$

  3. $324$ persons $/km^2$

  4. $424$ persons $/km^2$

Show answer
Correct Option: C
Explanation:
  • Increasing population is a challenging issue for the developing country like India. 
  • If the population increases more than its carrying capacity it may lead to a food crisis resulting in famines, hunger and poor health, an acute shortage of shelter and clothing. 
  • Spreading awareness among the people about the ill-effects of the increasing population may be helpful to control the over increasing population.
  • The population density of India according to 2001 is 324person per square kilometers.

So, the correct answer is option C.