# Biology Questions and Answers – Population Growth – 3

«
»

This set of Biology Online Test for BDS-Dental Entrance Exams focuses on “Population Growth – 3”.

1. Which of the following formula correctly defines natality?
a) Natality = $$\frac{Number \, of \, deaths \, per \, year}{Mid-year \, population}$$ x 1000
b) Natality = $$\frac{Number \, of \, births \, per \, year}{Mid-year \, population}$$ x 1000
c) Natality = $$\frac{Number \, of \, births + Number \, of \, deaths}{Mid-year \, population}$$ x 1000
d) Natality = Births – Deaths x 1000

Explanation: The natality is also known as the birth rate. It is the number of individuals born in a population at a specific time. For humans, it is described as a number of individuals born per 1000 of the population per year.

2. Which of the following formula correctly defines mortality?
a) Mortality = $$\frac{Number \, of \, deaths \, per \, year}{Mid-year \, population}$$ x 1000
b) Mortality = $$\frac{Number \, of \, births \, per \, year}{Mid-year \, population}$$ x 1000
c) Mortality = Number of deaths x 1000
d) Mortality = Number of births x 1000

Explanation: The growth rate is the increase in population due to an actual number of individuals added to the population. Usually in India, the growth rate is calculated every 10 years.

3. Which of the following formula correctly defines growth rate (GR)?
a) GR = $$\frac{Natality – Mortality}{Unit time}$$

b) GR = $$\frac{Natality – Natality}{Unit time}$$

c) GR = $$\frac{Mortality – Natality}{Unit time}$$

d) GR = $$\frac{Mortality – Mortality}{Unit time}$$

Explanation: The growth rate. It is the increase in population due to an actual number of individuals added to the population. Usually in India, the growth rate is calculated every 10 years.

4. The 10 individuals are born per year in a population, and the mid-year population is 5000. What is the birth rate of that area?
a) 20
b) 1.6
c) 4
d) 2

Explanation: As per the formula, Natality = $$\frac{Number \, of \, deaths \, per \, year}{Mid-year \, population}$$ x 1000 = $$\frac{10}{5000}$$ 1000 = 2
The birth rate of the given area is 2 per year.

5. The 20 individuals are born per year in a population, and the mid-year population is 5000. What is the birth rate of that area?
a) 20
b) 1.0
c) 4
d) 2

Explanation: As per the formula, Natality = $$\frac{Number \, of \, deaths \, per \, year}{Mid-year \, population}$$ x 1000 = $$\frac{20}{5000}$$ 1000 = 4
The birth rate of the given area is 4 per year.

6. The 80 individuals are born per year in a population, and the mid-year population is 5000. What is the birth rate of that area?
a) 20
b) 16
c) 4
d) 2

Explanation: As per the formula, Natality = $$\frac{Number \, of \, deaths \, per \, year}{Mid-year \, population}$$ x 1000 = $$\frac{80}{5000}$$ 1000 = 16
The birth rate of the given area is 16 per year.

7. The 100 individuals are born per year in a population, and the mid-year population is 5000. What is the birth rate of that area?
a) 2
b) 1.0
c) 20
d) 2

Explanation: As per the formula, Natality = $$\frac{Number \, of \, deaths \, per \, year}{Mid-year \, population}$$ x 1000 = $$\frac{100}{5000}$$ 1000 = 20
The birth rate of the given area is 20 per year.

8. The 20 individuals are dying per year in a population, and the mid-year population is 7000. What is the death rate of that area?
a) 13
b) 30
c) 2.8
d) 29

Explanation: As per the formula, Natality = $$\frac{Number \, of \, deaths \, per \, year}{Mid-year \, population}$$ x 1000 = $$\frac{20}{7000}$$ 1000 = 2.8
The birth rate of the given area is 2.8 per year.

9. The 25 individuals are dying per year in a population, and the mid-year population is 7000. What is the death rate of that area?
a) 13
b) 30
c) 2
d) 3.6

Explanation: As per the formula, Natality = $$\frac{Number \, of \, deaths \, per \, year}{Mid-year \, population}$$ x 1000 = $$\frac{25}{7000}$$ 1000 = 3.6
The birth rate of the given area is 3.6 per year.

10. The 75 individuals are dying per year in a population, and the mid-year population is 7000. What is the death rate of that area?
a) 13
b) 30
c) 10.7
d) 39

Explanation: As per the formula, Natality = $$\frac{Number \, of \, deaths \, per \, year}{Mid-year \, population}$$ x 1000 = $$\frac{75}{7000}$$ 1000 = 10.7
The birth rate of the given area is 10.7 per year.

11. The 95 individuals are dying per year in a population, and the mid-year population is 7000. What is the death rate of that area?
a) 200
b) 13.6
c) 100
d) 395

Explanation: As per the formula, Natality = $$\frac{Number \, of \, deaths \, per \, year}{Mid-year \, population}$$ x 1000 = $$\frac{95}{7000}$$ 1000 = 13.6
The birth rate of the given area is 13.6 per year.

12. If in a population the natality is 20 and mortality is 10, in a span of 10 years. What is the growth rate (GR) of that population?
a) 0
b) 20
c) 1
d) -10

Explanation: As per the formula, GR = $$\frac{Natality – Mortality}{Unit \, time} = \frac{20 – 10}{10}$$ = 1
The growth rate of the given area is 1 in 10 years.

13. If in a population the natality is 30 and mortality is 5, in a span of 10 years. What is the growth rate (GR) of that population?
a) 0
b) 2.5
c) 10
d) -10

Explanation: As per the formula, GR = $$\frac{Natality – Mortality}{Unit \, time} = \frac{30 – 5}{10}$$ = 2.5
The growth rate of the given area is 2.5 in 10 years.

14. If in a population the natality is 50 and mortality is 80, in a span of 10 years. What is the growth rate (GR) of that population?
a) 28
b) 100
c) 10
d) -3

Explanation: As per the formula, GR = $$\frac{Natality – Mortality}{Unit \, time} = \frac{50 – 80}{10}$$ = -3
The growth rate of the given area is -3 in 10 years.

15. If in a population the natality is 25 and mortality is 55, in a span of 10 years. What is the growth rate (GR) of that population?
a) -3
b) 100
c) 28
d) -38

Explanation: As per the formula, GR = $$\frac{Natality – Mortality}{Unit \, time} = \frac{25 – 55}{10}$$ = -3 