ECE #2

Question 1

What is a population?

Answer 1

A group of individuals of the same species living in a specific area.

Question 2

What are R-selected species? Give an example.

Answer 2

Species that reproduce rapidly, produce many offspring, and invest little in each. Example: mice or insects.

Question 3

What are K-selected species? Give an example.

Answer 3

Species that live in stable environments, produce few offspring, and invest heavily in each. Example: wolves or elephants.

Question 4

What is a community?

Answer 4

All the different populations of organisms living together in one area.

Question 5

What is an ecosystem?

Answer 5

A system that includes all living organisms and the flow of energy and matter between them and their environment.

Question 6

What are limiting factors?

Answer 6

Environmental resources or conditions (like food, water, or space) that restrict population growth when scarce.

Question 7

What is carrying capacity?

Answer 7

The maximum number of individuals an environment can sustainably support.

Question 8

What is exponential growth?

Answer 8

Growth where a population increases at a constant rate over time, proportional to its current size.

Question 9

What is a J-shaped curve?

Answer 9

A graph showing unrestricted population growth with unlimited resources.

Question 10

What is an S-shaped curve?

Answer 10

Growth that slows and stabilizes at the environments carrying capacity due to limiting factors like limiting resources, food, or space

Question 11

What is the difference between J-shaped and S-shaped curves?

Answer 11

J-curves show continuous growth with unlimited resources; S-curves show growth that slows as resources become limited.

Question 12

What is the Theory of Demographic Transition?

Answer 12

The model showing how populations shift from high birth and death rates to low birth and death rates as a country develops economically and socially.

Question 13

What is the fertility rate?

Answer 13

What is the fertility rate?

Question 14

What is the replacement fertility rate?

Answer 14

The number of children a woman must have to keep a population stable (about 2.1 in developed countries).

Question 15

What is the mortality rate?

Answer 15

The percentage of a population that dies from a specific cause in a certain time period.

Question 16

What is an emigrant?

Answer 16

A person who leaves their country to live elsewhere.

Question 17

What is an immigrant?

Answer 17

A person who enters a new country to live there permanently.

Question 18

What is net migration?

Answer 18

The difference between the number of immigrants and emigrants (immigrants − emigrants).

Question 19

What is the formula for net migration rate?

Answer 19

emmigrants-immigrants
_____________ x 1000
total population

Question 20

What factors directly affect population size?

Answer 20

Births, deaths, immigration, and emigration.

Question 21

How do you calculate population growth rate?

Answer 21

CBR - CDR + NMR
____________________
10

Question 22

What is the Crude Birth Rate (CBR)?**

Answer 22

the number of births in a year per 1000 people in the population,

Formula: # of live births/mid-year total population x 1000 = CBR

Question 23

What is the Crude Death Rate (CDR)?**

Answer 23

number of deaths in a population in 1 year per 1000 people in the population; Formula: Total number of deaths/Estimated mid-year population x 1000 = CDR

Question 24

What are characteristics of more developed countries?

Answer 24

High resources, good healthcare, stable jobs, and lower birth rates due to women’s education and employment.

Question 25

What are characteristics of less developed countries?

Answer 25

Limited resources, poor healthcare, high disease rates, and higher birth rates due to fewer opportunities for women.

Question 26

What does a declining population look like?

Answer 26

A narrow base and larger older population — resembles an inverted triangle.

Question 27

What does a stable population look like?

Answer 27

Even distribution across age groups — resembles a rectangle.

Question 28

What does a rapidly growing population look like?

Answer 28

A wide base with many young people — resembles a triangle.

Question 29

How do fertility rates and development levels relate?

Answer 29

In less developed countries, limited education and job opportunities lead to higher fertility. In more developed countries, education and careers lead to fewer children.

Question 30

How has population growth changed in developed nations over time?

Answer 30

Populations shifted from high birth/death rates to low birth/death rates — rapid growth followed by stability or decline due to industrialization and improved living conditions.

Question 31

What factors affect how quickly a country moves through demographic transition?

Answer 31

Education (especially for women) Access to healthcare and family planning Political stability Economic opportunities Cultural or religious beliefs

Question 32

What is the current human population?

Answer 32

About 8.2 billion people.

Question 33

How has it changed over time?

Answer 33

Rapid increase during the Industrial Revolution; growth has slowed since the 1960s due to declining fertility rates and longer life expectancy.

Question 34

How can technology affect population size?

Answer 34

Improves healthcare, agriculture, and education — increasing life expectancy and supporting larger populations.

Question 35

How do limiting factors affect population growth?

Answer 35

They slow or stop growth when resources become scarce, leading to competition, disease, or predation.

Question 36

Why is exponential growth unsustainable?

Answer 36

Because resources eventually run out, causing a population crash or decline.