Biology · Geography

Population Dynamics

940 Questions

Explore key concepts in population dynamics through these practice questions. The focus is on demographic transition models, population pyramids, and life history theory. These topics are useful for general studies and biology exams.

Demographic transition theoryPopulation pyramidsMathematical growth modelsLife history theory

Population Dynamics Questions

Multiple choice

What happens during the transitional stage of the demographic transition?

  1. Birthrates begin to fall

  2. Death rates begin to fall

  3. Birth rates increase

  4. Death rates increase
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In the demographic transition model, the transitional stage is characterized by a significant drop in death rates due to improvements in medicine, sanitation, and food supply, while birth rates remain high.

Multiple choice senescence senescence and death plant growth plant growth and development biology

Senescent phase of an organism's life span can be recognised by

  1. Slow metabolism

  2. Cessation of reproduction

  3. Decreased immunity

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
The terminal irreversible stage of ageing is called senesence. This is the last phase of life span, that ultimately leads to death. This phase can be recognised by slow metabolism, cessation of reproduction and decreased immunity.

So, the correct answer is 'All of the above'.

Multiple choice business mathematics and statistics sampling methods population and sampling basic concepts of sampling sampling techniques and statistical inference

Population are unlimited in size are referred to as____________.

  1. infinite populations.

  2. finite populations.

  3. census method.

  4. none of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Population refers to an entire set of people or objects present for the purpose of gathering data and when the population is unlimited in size i.e. it cannot be ascertained easily, it is known as infinite population.

Multiple choice biology living organisms and their surroundings living organism living vs nonliving living vs non living

Growth is a

  1. Reversible increase in size

  2. Reversible increase in shape

  3. Irreversible increase in size

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Growth is defined as the positive and irreversible change in size and mass over the period of time. It is shown by all living organisms. It occurs by an increase in cell size or number. In animals, growth is observed up to certain period of time only whereas plants shows continuous growth throughout the lifetime. 

Thus, the correct answer is option C.

Multiple choice commercial applications population - the increasing numbers and rising problem impact of depletion of natural resources population growth models depletion of resources

The logistic population growth model, dN/dt = rN (K N/K), describes a populations growth when an upper growth is assumed. This upper limit to growth is known as the population's___  ,and as N gets larger,dN/dt________

  1. Biotic potential, increases

  2. Biotic potential, decreases

  3. Carrying capacity, increases

  4. Carrying capacity, decreases
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
  • The logistic population growth model is represented by :
dN/dt = rN (K-N/ K)
Where, N = Population density at time t
r = Intrinsic rate of natural increase
K = Carrying capacity
  • In nature, a given habitat has enough resources to support a maximum possible number, beyond which no further growth is possible. This limit is known as nature’s carrying capacity (K) for that species in that habitat.
  • As the value of N increases, the rate of growth dN/dt decreases. 
So, the correct option is 'Carrying capacity, decreases'.

Multiple choice commercial applications population - the increasing numbers and rising problem impact of depletion of natural resources population growth models depletion of resources

A pattern of idealized population growth, restricted by limiting factors is shown by

  1. Logistic growth model

  2. Carrying capacity model

  3. Dispersion model

  4. Habitat cap model

  5. Exponential growth model
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Population growth rate measures the number of individuals in a population (N) over time (t). When the conditions are ideal, the type of growth is known as exponential form of growth which is expressed by the equation, (dN)/(dt)= rN. When the limiting factors is restricted, the growth pattern is known as logistic growth model. This model is described by the differential equation (dN)/(dt)= rN(K-N)/K, where K is the carrying capacity and r is the maximum per capita growth. 

Therefore, the correct answer is option A.

Multiple choice commercial applications population - the increasing numbers and rising problem impact of depletion of natural resources population growth models depletion of resources

A logistic growth curve depicting a population that is limited
by a definite carrying capacity is shaped like the letter

  1. J

  2. L

  3. M

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

A logistic growth curve that is limited by a definite carrying capacity is shaped like the letter 'S' or a sigmoid curve, which is differentiated into three parts the Lag phase, the Log phase or the exponential growth phase and the stationary or plateau phase. At this phase the amount of resources cannot support the growing population, due to which the number of members in the population is prevented from increasing

So, the correct answer is 'S'

Multiple choice commercial applications population - the increasing numbers and rising problem impact of depletion of natural resources population growth models depletion of resources

dN/dt is 

  1. Rate of births

  2. Rate of deaths

  3. Change in population size

  4. Carrying capacity
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The rate of change in a population can be defined as the ratio of total change in population and time taken for that change. Change in population size can be defined as difference in population size at the end and between the beginning of a particular time period

So, the correct answer is 'Change in population size'

Multiple choice commercial applications population - the increasing numbers and rising problem impact of depletion of natural resources population growth models depletion of resources

In ecology, N/S represents ____________.

  1. Population density

  2. Rate of growth

  3. Rate of deaths

  4. Rate of births
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In ecological formulas, N typically represents the total population size and S represents the area or space, so N/S represents population density.

Multiple choice commercial applications population - the increasing numbers and rising problem impact of depletion of natural resources population growth models depletion of resources

Sigmoid growth curve occurs where growth pattern is 

  1. Logistic

  2. Exponential

  3. Accretionary

  4. Geometric
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Logistic growth model:- Sigmoid growth curve occurs where growth pattern is logistic. Unconstrained natural growth is exponential growth. A biological population with food, space to grow, and no threat from predators, tends to grow at rate proportional to population.
$\dfrac{dP}{dt}=rp$
where p$=$population function of time t
r$=$ proportionality constant.
Multiple choice commercial applications population - the increasing numbers and rising problem impact of depletion of natural resources population growth models depletion of resources

Asymptote in a logistic growth curve is obtained when:

  1. $K=N$
  2. $K>N$
  3. $K<n$< div=""></n$<>

  4. The value of r approaches zero
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In logistic growth, the asymptote (carrying capacity K) is reached when N = K (population equals carrying capacity). At this point, population growth stops because resources limit further growth. When K > N, population is still growing. Option C has garbled formatting but would represent K < N, which is impossible.

Multiple choice commercial applications population - the increasing numbers and rising problem impact of depletion of natural resources population growth models depletion of resources

Choose the incorrect one.

  1. In logistic growth equation when N $<$ K then r $> 0$
  2. In logistic growth equation when N$=$K then r$=$constant
  3. In logistic growth equation N $>$ K then r $< 0$
  4. In logistic growth equation N $>$ K then r $> 0$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Answer is A. 
If N is very small compared to K, then the population growth rate will be a small positive number. This means the population is slowly getting larger because there are a few more births than deaths

Multiple choice geography ideas of development study of population in tamil nadu population and migration human geography in tamil nadu

The difference between birth and death rates, when expressed in percentage, is known as the _____.

  1. Growth rate

  2. Index

  3. Rise

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The difference between birth and death rates gives the natural increase of population of regions. When expressed in percentage it is known as the growth rate. The annual growth rate of Tamil Nadu's population is 1.1% which is lower than that of India.