Ecological Relationships And Energy Flow

Question 1

Define biodiversity

Answer 1

A measure of the number of the different species living in an area

Question 2

Define population

Answer 2

The number of organisms of the same species living in an area

Question 3

Define habitat

Answer 3

Where a population lives

Question 4

Define environment

Answer 4

An organisms surroundings. It contains factors that influence the organism. These factors can be divided into abiotic and biotic.

Question 5

Define community

Answer 5

Several populations of different species living in habitats close together

Question 6

Define ecosystem

Answer 6

An area where a community of organisms live and are affected by a range f environmental factors

Question 7

What is an abiotic factor

Answer 7

Non living factors e.g temperature

Question 8

Define biotic factors

Answer 8

A living factor e.g a predator

Question 9

Name abiotic factors

Answer 9

Wind speed
Water / soil moisture
Light
Temperature
pH levels

Question 10

How does wind speed affect organisms

Answer 10

It affects the rate of water loss by plants and therefore affects their survival rates in exposed areas.

Question 11

How does water / soil moisture affect organisms

Answer 11

It’s measured by finding mass difference between the wet soil and it being dried out. Affects survival and therefore distribution of plants and animals.

Question 12

How does light affect organisms

Answer 12

Measured using a light meter. Affects the survival and therefore distribution of plants as they light to photosynthesise.

Question 13

How does temperature affect organisms

Answer 13

Messier with thermometer. Affects rate of cell reactions like photosynthesis and diffusion.

Question 14

How does pH affect organisms

Answer 14

Measured using soil test kits or probes. The pH of soil is very important in distribution of many plants. Some plants will only grow in relative acid soils or relative alkaline soils. But most plants prefer to grow in neutral pH.

Question 15

What are the biotic factors for animals

Answer 15

Competition between
Food
Water
Territory
Mates

Question 16

What are biotic factors between plants

Answer 16

Competition between
Light
Water
Minerals
Space

Question 17

What is a quadrat

Answer 17

A square frame used to measure a sample of an area.

Question 18

Why are quadrants used

Answer 18

To investigate the distribution of organisms in a habitat

Question 19

What makes a quadrat investigation reliable

Answer 19

A large sample needs to be obtained. For example 20 small sections should be sampled for a large area

Question 20

Define representative

Answer 20

It needs to be representative of the entire area being investigated. In other words sampling should take place randomly across the larger area, not just concentrated in one part.

Question 21

What is the method for quadrat random sampling

Answer 21

1. Divide the area to be sampled into a grid using tape measures placed at right angles to each other.
2. Use random number generator to generate coordinates within the grid to place the quadrat.
3. Place quadrat at each coordinate
4. Count the numbers / estimate percentage cover of each species in each quadrat.
5. Use a key to identify each species
6. Record results in a table.
7. Calculate the average of each species.

Question 22

What is a belt transect

Answer 22

It’s a method that is used when there is a gradual change from one side of a habitat to another, like the change in light between the outer edges of a forest to the centre.

Question 23

What is the method for the belt transcet

Answer 23

1. Extend a measuring tape from one side of the habitat to another
2. Place a quadrat at 0m on the tape
3. Count the numbers / estimate percentage of each species.
4. Use a key to identify each species.
5. Record results in a table.
6. Continue this up the tape measure until the end
7. Calculate average of each species
8. A bar chart can be drawn to who the data obtained.