Tag: zoology

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Questions Related to zoology

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

"Verhulst-Pearl" logistic growth is described using the equation $\dfrac{dN}{dt}=rN(\dfrac{K-N}{K})$. In this K stands for

  1. Temperature in degree Kelvin

  2. Intrinsic rate of natural increase

  3. Carrying capacity

  4. Population density
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
The population growth rate is measured in number of individuals in a population (N) over time (t). The term for population growth rate is written as (dN/dt). The d just means change. K represents the carrying capacity, and r is the maximum per capita growth rate for a population. Per capita means per individual, and the per capita growth rate involves the number of births and deaths in a population. The logistic growth equation assumes that K and r do not change over time in a population.

So, the correct answer is 'C'.
Multiple choice zoology human population population ecology population size population and how it changes

A high density of elephant population in an area can result in :-

  1. Predation on one another

  2. Mutualism

  3. Intra specific competition

  4. Inter specific competition
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
A high density of elephant population in an area can result in intra specific competition as elephants as a species will require the same resources or will be surviving in the same niche and with greater density of population the resources will be limited as compared to the number of individuals
So, the correct answer is 'Intra specific competition'
Multiple choice zoology human population population ecology population size population and how it changes

For which of the following cases, population density can be easily determined by utilizing non-biological parameter?

  1. Fish density

  2. Density of bacteria in culture plate

  3. Siberian cranes at Bharatpur wetlands

  4. Tiger census
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Non biological parameters of water can be easily used to determine the population density of the fishes.

Bacteria, Siberian cranes and Tigers are impacted heavily by biological parameters and their population cannot be just estimated on the basis of non biological parameters.
These parameters include :

  1. Presence of heavy metals
  2. pH of water
  3. Mineral content like nitrates and phosphorus
  4. Temperature
  5. Dissolved oxygen
  6. Turbidity
So the correct answer is 'Fish'.
Multiple choice zoology human population population ecology population size population and how it changes

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

  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.
Reveal answer Fill a bubble to check yourself
B Correct answer
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.'

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

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

  1. 0.01

  2. 0.8

  3. 8

  4. 50
Reveal answer Fill a bubble to check yourself
B Correct answer
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'
Multiple choice zoology human population population ecology population size population and how it changes

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

  1. Pakistan

  2. India

  3. Japan

  4. Bangladesh
Reveal answer Fill a bubble to check yourself
D Correct answer
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.

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

The best way to reduce the population of undesirable species is

  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
Reveal answer Fill a bubble to check yourself
A Correct answer
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.

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

Indian state having highest population density is

  1. Kerala

  2. West Bengal

  3. Maharashtra

  4. Punjab
Reveal answer Fill a bubble to check yourself
B Correct answer
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. 

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

Which one has mainly controlled human population density?

  1. Industry

  2. Natural resources

  3. Climate

  4. Communication
Reveal answer Fill a bubble to check yourself
B Correct answer
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.
Multiple choice zoology human population population ecology population size population and how it changes

The density of population can be calculated

  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
Reveal answer Fill a bubble to check yourself
A Correct answer
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.