Environmental Studies

Question 1

Population ecology

Answer 1

The factors influencing the population size, growth rate, growth forms and distribution of individuals inside a population

Question 2

Individual

Answer 2

A single organism that forms part of a species

Question 3

Species

Answer 3

A group of organisms with similar characteristics. which produce fertile offspring

Question 4

Population

Answer 4

A group of organisms of the same species that are found in a particular area and can crossbreed freely

Question 5

Community

Answer 5

A group of populations occurring in a particular area

Question 6

Ecosystem

Answer 6

A unit of plant and animal communities in interaction with each other as well as with the non-living factors in a particular area

Question 7

Environment

Answer 7

The external factors, living and non-living, surrounding an organism and influencing its development and survival

Question 8

Habitat

Answer 8

The specific environment in which a plant or animal species normally occurs

Question 9

Population size

Answer 9

The total number of individuals in a population

Question 10

Population density

Answer 10

The number of individuals of a population per unit area

Question 11

Population Parameters

Answer 11

Natality
Mortality
Immigration
Emigration

Question 12

Determining population size

Answer 12

• Direct technique > Census

- Indirect technique > Mark-recapture/Quadrant

Question 13

Environmental resistnace

Answer 13

All limiting factors that prevent unlimited growth in a population

Question 14

Examples of limiting factors

Answer 14

• Shortage of food and water
• Shortage of living space
• Shortage fo shelter
• Predation
• Disease and parasitism
• Accumulation of toxins

Question 15

Population growth forms

Answer 15

• Geometric J-shaped

- Logistic S-shaped

Question 16

Carrying capacity

Answer 16

The maximum number of individuals that a specific environment can sustain

Question 17

Stable population

Answer 17

A population whos numbers fluctuate around the carrying capacity

Question 18

Migration

Answer 18

When a population moves from its original habitat and returns later

Question 19

Density dependent factors

Answer 19

Limiting factors that increase or take effect when the population numbers increase

Question 20

Density independent factors

Answer 20

Factors that regulate population size regardless of the size or density of the population

Question 21

Culling

Answer 21

The selective killing of wild animals when their numbers exceed the carrying capacity of their habitat

Question 22

Trophic level

Answer 22

The position an organism or group of organisms occupies in the food chain

Question 23

Producers

Answer 23

All green plants that are able to photosynthesis and thus produce their own food

Question 24

Consumers

Answer 24

Organisms that cannot produce their own food, and are directly or indirectly dependent on hte producers or other consumers for their food

Question 25

Primary consumers

Answer 25

Herbivores | Omnivores

Question 26

Secondary consumers

Answer 26

Carnivores eating primary consumers Scavengers Omnivores

Question 27

Tertiary consumers

Answer 27

Carnivores eating secondary consumers

Question 28

Decomposers

Answer 28

Bacteria and fungi that feed on dead organic material

Question 29

Five community interactions

Answer 29

- Predation - Competition - Mutualism - Commensalism - Parasitism

Question 30

Predator adaptions

Answer 30

- Agility - Great speed - Intensified sense of sight and smell - Sharp teeth and claws - Good camouflage

Question 31

Prey adaptions

Answer 31

- Herding - Good camouflage - Warning colouration - Ability to secrete poisonous substances

Question 32

Resource partitioning

Answer 32

When the same resources are used differently by two species in the same habitat, allowing for co-existance

Question 33

Types of resource partitioning

Answer 33

- Different times - Different parts - Different habitats

Question 34

Ecological succession

Answer 34

The sequence of communitites, where one community replaces another over time, resulting in long-term changes in the ecosystem

Question 35

Primary succession

Answer 35

When plants and animals settle for the first time in a new habitat that previously had no life

Question 36

Secondary succession

Answer 36

When plants and animals settle in a new habitat disrupted by human activities

Question 37

Human population growth

Answer 37

J-shaped

Question 38

Reasons for human growth

Answer 38

- Medical advances | - Agricultural advances

Question 39

Age structure distribution

Answer 39

Number of individuals per age group in a specific population > pre-reproductive group > reproductive group > post-reproductive group

Question 40

Gender distribution

Answer 40

The population ratio of male individuals to female individuals

Question 41

Population pyramids

Answer 41

- Rapid population growth - Stable population growth - Negative population growth

Question 42

Ecological footpring

Answer 42

The amount of bioogically productive land and water required to regenerate the resources consumed by the human population, and to absorb and detoxify the human waste produced

Question 43

Biocapacity

Answer 43

The amount of land and water available on earth to provide resources and absorb waste

Question 44

Conservation

Answer 44

The protection of endangered plant and animal species

Question 45

Sustainability

Answer 45

To meet current needs without adversely affecting the survival of other species or future generations