B11: ECOLOGY

Question 1

What is ecology

Answer 1

Ecology is the study of interrelationships of living organisms with each other

Question 2

Define environment

Answer 2

The combination of factors that surround and act upon an organism

Question 3

What are abiotic factors

Answer 3

All the non-living factors

Question 4

Define habitat

Answer 4

The place where a particular organism lives

Question 5

Define species

Answer 5

A group of organisms that closely resemble each other and are normally capable of interbreeding to produce fertile offspring.

Question 6

Define population

Answer 6

All the members of particular species living together in a particular habitat.

Question 7

Define community

Answer 7

All the populations of different species living together in a particular habitat.

Question 8

Define ecosystem

Answer 8

A community of living organisms interacting with each other and with their abiotic environment

Question 9

Niche

Answer 9

The position or role of an organism with an ecosystem

Question 10

Sampling techniques

Answer 10

1.Pooter 2.Plankton net 3.Pitfall trap 4.Tullgren funnel 5.Beating tray 6.Seives 7.Sweep Nets 8.Transects 9.Quadrats

Question 11

Define abiotic factors. give examples

Answer 11

all the non-living features of an ecosystem that influence the organisms in the community. eg. latitude, altitude, water, oxygen, temperature, carbon dioxide concentration, light intensity, rainfall, pH, mineral oil content, salt content

Question 12

Define biotic factor and give examples

Answer 12

biotic factors are the influences that living organism in community have on each other examples: food water disease, predation, competition for food, water , edaphic factors and living space.

Question 13

How to estimate population size

Answer 13

1. results from quadrats 2. capture-recapture method

Question 14

How to use quadrats to measure population size

Answer 14

1. Species Population density: averaging the amount of organism found in the quadrat usually meter squared or cm squared. 2. Total species population: total number in individuals in the area of study. Found by multiplying the species density by the area of the ecosystem studied.

Question 15

How to use Mark-Release-Recapture method to estimate population size.

Answer 15

used for moving animals. A sample of animals of a species is counted and marked an then released. After some time a second sample is obtained and the umber of marked organisms obtained. The following equation is used to estimate the population: Estimated population size = (number captured and marked) X (number recaptured) / number of marked organisms recaptured.

Question 16

Examples of comensalism

Answer 16

Egrets and cows. Egrets eat the ticks from the cows but the cows are not affected.

Question 17

Examples of Parasitism

Answer 17

tapeworms in the intestines of humas; lice and ticks, Yellow Dodder and another plant.

Question 18

Examples of mutualism

Answer 18

Legumes and nitrogen fixing bacteria.

Question 19

what is a line transect

Answer 19

A sampling method used to measure the distribution of organisms between two points. A tape or string laid along the ground in a straight line between two poles. Sampling is rigorously confined to organisms that are actually touching the line.

Question 20

what is a belt transect

Answer 20

This is similar to the line transect method but gives information on abundance as well as presence, or absence of species. It may be considered as a widening of the line transect to form a continuous belt, or series of quadrats. In this method, the transect line is laid out across the area to be surveyed and a quadrat is placed on the first marked point on the line.

Question 21

Pooter (aspirator)

Answer 21

is a device used in the collection of insects, crustaceans or other small, fragile organisms, usually by aspirating(sucking) one end into a collecting jar.

Question 22

What is a plankton net?

Answer 22

A funnel-shaped, fine-meshed net that is towed through the water. The net concentrates the plankton from hundreds of gallons of water that pass through it and collected

Question 23

what is a Sweep net

Answer 23

Large nets used to catch flying insects

Question 24

what is Pond Net

Answer 24

Nets similar to sweeping nets but made of stronger netting used to capture aquatic animals and vegetation

Question 25

What is a pitfall trap?

Answer 25

cans or jars buried into the ground used to collect ground dwelling animals. they enter the trap but are unable to leave. It usually has a cover to prevent rain from entering and has paper or cardboard on the inside which serves as protection.

Question 26

What is a Tullgren Funnel

Answer 26

is an apparatus used to extract living organisms, particularly arthropods, from samples of soil. The Tullgren funnel works by creating a temperature gradient over the sample so that mobile organisms will move away from the higher temperatures and fall into a collecting vessel, where they perish and are preserved for examination.

Question 27

What is this aparratus?

Answer 27

Tullgren funnel

Question 28

what is this apparatus?

Answer 28

Pooter

Question 29

what is this apparatus?

Answer 29

Pond Net

Question 30

what is this apparatus?

Answer 30

Pitfall trap

Question 31

what is this apparatus?

Answer 31

sweep net

Question 32

what is this apparatus?

Answer 32

plankton net

Question 33

what are edaphic factors

Answer 33

abiotic factors related to the soil such as; Texture and composition water content air content mineral content pH Humus

Question 34

What is soil?

Answer 34

a mixture of inorganic rock particles, water, air, mineral salts, organic matter and living organisms including microorganisms.

Question 35

Physical features of soil

Answer 35

• Water content
• water holding capacity
• air content
• pH
• salinity
• organic and mineral matter
• light
• temperature

Question 36

what are the important components of soil and air?

Answer 36

• Oxygen
• Nitrogen
• Carbon dioxide