Organsims in the environment Y9

Question 1

What is the definition of the Ecosystem?

Answer 1

A group of interrelated organisms and their physical environment in a particular area e.g. pond, desert etc. The biotic and abiotic components interact with each other

Question 2

What is the definition of Population?

Answer 2

The numbers of one particular species living in an area at the same time.

Question 3

What is the definition of Community?

Answer 3

The populations of all species in an ecosystem at any one time

Question 4

What is the definition of Habitat?

Answer 4

The place in which an organism lives

Question 5

What is Ecology?

Answer 5

The study of the relationship between organisms and their environment

Question 6

What is Abiotic Factor? and examples?

Answer 6

The non-living physical conditions in an ecosystem e.g. light intensity, temperature, rainfall

Question 7

What is Biotic Factor? and examples?

Answer 7

The effects of the activities of living organisms on other organisms e.g. food availability, predation, competition, disease

Question 8

What is a trophic level?

Answer 8

the position in a food chain/food web/pyramid e.g. producer or primary consumer

Question 9

What is a food web?

Answer 9

a network of interconnected food chains showing the flow of energy through an ecosystem

Question 10

What do the arrow in the food chains show?

Answer 10

The arrows in food chains and food webs shows the flow of energy

Question 11

What is the advantage on feeding on more than one organism?

Answer 11

Survive if an organism dies out
Supply for different seasons
Easier to find prey

Question 12

How can we estimat ethe population of a forest etc:

Answer 12

Using quadrats.

Question 13

How do we use Quadrats?

Answer 13

Use a tape measure to determine the area of the field ii. Place quadrats around the whole field. iii. To avoid bias, we must place quadrats randomly. This is NOT done by throwing them, but instead by using coordinates that have been randomly generated. iv. Count the number of plants in each quadrat. v. Multiply up to estimate the population of each species in the whole field vi. To ensure a reliable mean, we must take many repeats.

Question 14

How much energy is transferred from one trophic level to the next?

Answer 14

10%

Question 15

Where is energy lost between the Sun and the Producer?

Answer 15

Light energy is not absorbed by chlorophyll

Question 16

Where is enrgy lost between the producer and the primary consumer?

Answer 16

Excretion by the plant, not all the producer is eaten, egestion by the consumer and heat loss due to respiration

Question 17

Where is energy lost between consumers?

Answer 17

Excretion by the consumer, egestion, not all the consumer is eaten, heat lost due to respiration, movement

Question 18

What does the pyramid of Biomass show us?

Answer 18

each bar represents the mass of dry organic material (biomass) at each trophic level.

Question 19

How can the Biomass be calculated?

Answer 19

This can be calculated by gently warming the fresh mass of organisms at each trophic level (to remove water), and then using a mass balance

Question 20

Which pyramid(s) will always have a pyramidal shape? Why?

Answer 20

Biomass/energy. Due to excretion, egestion, and not all the organism being eaten, both mass and energy will be lost at each trophic level.

Question 21

Pyramid of energy?

Answer 21

the width of each bar represents the amount of energy passing through each trophic level.

Question 22

Eg of Biotic Factors?

Answer 22

Availabillity of food
Predation
Parasitism
Disease

Question 23

Eg of Abiotic Factors?

Answer 23

Climate, temp, light intensity hours of daylight, soil conditions and pollution, O2 conc. pH.