4.7 Energy Efficiency

Losses in the owl is from respiration, producing energy for flight, digestion, movement, the nervous system.
All organisms finally die and are broken down by micro-organisms living on the dead and decaying remains of other micro-organisms.
100Kj of grass energy represents grass eaten by the herbivore.
Mouse have to walk around and find their food and carry out the process of respiration.
90Kj of energy left is lost from respiration and undigested food.

4.6 Energy and substances in food chains

- Bushgrass eaten by impala - Bushgrass is the producer, Impala is the primary consumer, leopard is the secondary consumer, lion is the tertiary
- producer turns light energy into chemical energy - takes the form of organic molecules including carbohydrates, proteins and lipids --> what we call food
- These molecules are composed of C-H bonds, C-O bonds, C-C bonds, O-H bonds and C-N bonds - ALL represent energy
- C H O N are the substances/matter - contain the energy from the sunlight
- Impala consumes this for growth and respiration and life processes - then the leopard consumes the impala passing on the same molecules, reorganizes them into leopard form and then to the lion who reorganizes them as well
- What is passing is the 'matter' and energy (in the bonds)

These molecules are composed of C-H bonds, C-O bonds, C-C bonds, O-H bonds and C-N bonds - ALL represent energy.

4.5b Food Webs

Food webs allow better description of the ecosystem.
Food web allows us to show organisms feeding at different trophic levels.
Organisms can have multiple predators.
Organisms may be feeding on multiple pray.
Results in food chains becoming linked.
eg:
- producer is grass
- P.C - rabbit, beetles, slugs, mice, woodlice
- S.C - small birds, badger, hawk
- T.C - Hawk

4.5a Food Chains

- Food China links together Producer to the 1st consumer, 2nd consumer and 3rd consumer.
- Only one organism per trophic level
- Food chain cannot show an organism being an omnivore
- Cannot show them feed at more than 2 trophic levels
- Food chains show the flow of matter and energy

4.4 Trophic Levels

- trophic means to feed
- carrot plant - photosynthesis - PRODUCER
- carrot fly - is a herbivore because it is eating part of the carrot plant - PRIMARY CONSUMER
- Fly catcher - Carnivore because it eats the carrotfly - SECONDARY CONSUMER
- Sparrow Hawk - Top carnivore eats the flycatcher - TERTIARY CONSUMER


Producer turns light energy into chemical energy.
Primary Consumer takes in the chemical energy of the plant and changes it into chemical energy of the fly.
All organisms die and are then broken down by decomposers of fungi and bacteria.

4.3 Quadrates samples

The sample needs to be random (bias).
The second part of the sample is that it needs to be representative (large).
A sample needs to be big enough so the estimate has to be close to the real population.
The grid system is going to work like the x,y coordinates on a graph you would draw.
The random numbers are used to generate a number for the x and y coordinates and will tell us where to take a sample from.

The sample needs to be random (bias).
The second part of the sample is that it needs to be representative (large).
A sample needs to be big enough so the estimate has to be close to the real population.
The grid system is going to work like the x,y coordinates on a graph you would draw.
The random numbers are used to generate a number for the x and y coordinates and will tell us where to take a sample from.

4.2 Quadrates

Quadrates are used to estimate the population size of an organism in two different areas.
All ecosystems are made up of a number of populations which formed the community.
The technique is called quadrating, it is based on squares and can be made from an material.
They form square grids which can consist of 0.25 meter or 1 meter.
Quadrates are a method of sampling different locations so populations can be compared in two different locations.

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4.1 Ecosystems

A community of organisms consist of a population of different species.
The habitat includes the non biological factors.
The environment could have the cycle of daylight with dark, the temperature, rainfall, humidity and slope of the land.
All the factors have something in common; they are all non biological.
The community which is made up from different species interact with each other.

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