1
,Table of Contents
Environmental Studies – Human influences on the environment.........................................................3
Genetics and genetic engineering........................................................................................................20
DNA – life at a molecular cellular and tissue level...............................................................................38
Evolution..............................................................................................................................................53
Human Endocrine System....................................................................................................................88
Human Reproduction - Male reproductive system..............................................................................97
Female Reproductive Tract................................................................................................................100
POPULATION ECOLOGY.....................................................................................................................128
Reproduction in flowering plants......................................................................................................139
2
, Environmental Studies – Human influences on the
environment
Humans gradually change the environment they live in
Resent human explosion in the rate of change has accelerated, upsetting the
balance in natural ecosystems and threatening the continuation of life on
earth
What makes up the environment?
- Habitat - the place where an organism lives
- Abiotic and biotic conditions make up the environment and support life
- Abiotic (temperature, humidity, light, water)
- Biotic (living organisms)
What makes an environment sustainable?
- A sustainable environment is achieved by using the natural resources at a
controlled rate so that they do not run out and damage the environment
- Natural resources are the resources produced by nature that are useful or
necessary for life
can be physical (land, water, air)
can be biological (plants and animals)
- Non-renewable - resources that are not replaced by natural processes within
an average lifespan
- Renewable - Those capable of being regenerated within the average lifespan
of humans
- Sustainable development refers to development of industry, agriculture and
housing to improve the quality of life without damaging the earths renewable
resources
- To do this ecological balance, economic growth and social responsibility must
all work together
3
, How are humans affecting the environment?
- The world population has increased a lot and this demands an increase in
housing, medicine and thus using more of the natural resources.
- Humanities' ecological footprint has grown so fast that the planet’s resources
are being used faster than what they can be generated’
Human activity is polluting the environment
- Air
- Water
- Land
1. Pollution
The addition of any element into an ecosystem which causes damage to the living
organisms or to the environment
Air Pollution
- An abiotic factor that is vital for the survival of all living organisms
- It is made of 20.94% oxygen
- 78.095 nitrogen
- A very small quantity of other elements
- Made of gases liquids and solids
- Solids present in the atmosphere at levels high enough to harm living
organism
- Natural processes such as volcanic eruptions release chemicals into the air
- Human activities also release chemicals into the air, factories
Pollutants may be:
- Primary which is substances given off directly into the
atmosphere such as carbon dioxide from burning fossil fuels
- Secondary which is substances that are formed in the air from
the reaction of primary pollutants such as sulphuric acid
What causes air pollution?
Air pollution has increased due to human population densities and
industries
This has caused an increase in the amount of energy needed for
industry transportation and domestic use
To release energy and generate more electricity, more:
- Coal fore stations are being built to generate more electricity by burning coal
- Motor vehicles and aeroplanes are burning petrol and diesel releasing more
exhaust fumes
- Wood is being burnt for cooking and heating homes which release smoke
fumes
- Grass and forest fires are occurring, releasing smoke and gas into the air
4
,Table of Contents
Environmental Studies – Human influences on the environment.........................................................3
Genetics and genetic engineering........................................................................................................20
DNA – life at a molecular cellular and tissue level...............................................................................38
Evolution..............................................................................................................................................53
Human Endocrine System....................................................................................................................88
Human Reproduction - Male reproductive system..............................................................................97
Female Reproductive Tract................................................................................................................100
POPULATION ECOLOGY.....................................................................................................................128
Reproduction in flowering plants......................................................................................................139
2
, Environmental Studies – Human influences on the
environment
Humans gradually change the environment they live in
Resent human explosion in the rate of change has accelerated, upsetting the
balance in natural ecosystems and threatening the continuation of life on
earth
What makes up the environment?
- Habitat - the place where an organism lives
- Abiotic and biotic conditions make up the environment and support life
- Abiotic (temperature, humidity, light, water)
- Biotic (living organisms)
What makes an environment sustainable?
- A sustainable environment is achieved by using the natural resources at a
controlled rate so that they do not run out and damage the environment
- Natural resources are the resources produced by nature that are useful or
necessary for life
can be physical (land, water, air)
can be biological (plants and animals)
- Non-renewable - resources that are not replaced by natural processes within
an average lifespan
- Renewable - Those capable of being regenerated within the average lifespan
of humans
- Sustainable development refers to development of industry, agriculture and
housing to improve the quality of life without damaging the earths renewable
resources
- To do this ecological balance, economic growth and social responsibility must
all work together
3
, How are humans affecting the environment?
- The world population has increased a lot and this demands an increase in
housing, medicine and thus using more of the natural resources.
- Humanities' ecological footprint has grown so fast that the planet’s resources
are being used faster than what they can be generated’
Human activity is polluting the environment
- Air
- Water
- Land
1. Pollution
The addition of any element into an ecosystem which causes damage to the living
organisms or to the environment
Air Pollution
- An abiotic factor that is vital for the survival of all living organisms
- It is made of 20.94% oxygen
- 78.095 nitrogen
- A very small quantity of other elements
- Made of gases liquids and solids
- Solids present in the atmosphere at levels high enough to harm living
organism
- Natural processes such as volcanic eruptions release chemicals into the air
- Human activities also release chemicals into the air, factories
Pollutants may be:
- Primary which is substances given off directly into the
atmosphere such as carbon dioxide from burning fossil fuels
- Secondary which is substances that are formed in the air from
the reaction of primary pollutants such as sulphuric acid
What causes air pollution?
Air pollution has increased due to human population densities and
industries
This has caused an increase in the amount of energy needed for
industry transportation and domestic use
To release energy and generate more electricity, more:
- Coal fore stations are being built to generate more electricity by burning coal
- Motor vehicles and aeroplanes are burning petrol and diesel releasing more
exhaust fumes
- Wood is being burnt for cooking and heating homes which release smoke
fumes
- Grass and forest fires are occurring, releasing smoke and gas into the air
4
