BY CHi hoa, an phong, long
~NOTES FOR FINALS~
I. 1.1 1.2 Photosynthesis
● Photosynthesis is an endothermic reaction in which energy from sunlight is
transferred to the chloroplasts in green plants
○ Green plants use this energy to make the carbohydrate glucose from the raw
materials carbon dioxide and water
○ At the same time, oxygen is made and released as a waste product
● Photosynthesis can be defined as the process by which plants manufacture
carbohydrates from raw materials using energy from light.
● Photosynthesis can be summarised in a word equation as shown below:
●
● This equation can also be shown as a balanced chemical equation
○ Six carbon dioxide molecules combine with six water molecules to make one
glucose molecule and six oxygen molecules
●
○ The products of photosynthesis
■ Plants use the glucose they make as a source of energy in respiration
■ They can also use it to
By Chi Hoa, An Phong, Long
, ● Produce starch for storage
● Synthesise lipids for an energy source in seeds
● To form cellulose to make cell walls
● Produce amino acids (used to make proteins) when combined
with nitrogen and other mineral ions absorbed by roots.
●
II. 1.3 The carbon cycle
● Nutrients such as carbon and nitrogen are not endless resources, and so, they
need to be recycled in order to allow new organisms to be made and grow
○ Carbon is taken out of the atmosphere in the form of carbon dioxide by plants
to be used for photosynthesis
○ It is passed on to animals (and microorganisms) by feeding
○ It is returned to the atmosphere in the form of carbon dioxide by plants,
animals and microorganisms as a result of respiration
○ If animals and plants die in conditions where decomposing microorganisms
are not present the carbon in their bodies can be converted, over millions of
years and significant pressure, into fossil fuels.
○ When fossil fuels are burned (the process is known as combustion), the
carbon combines with oxygen and carbon dioxide is released into the
atmosphere
■ Increased use of fossil fuels is contributing to an increase in the
carbon dioxide content of the atmosphere
By Chi Hoa, An Phong, Long
, ○ In addition, mass deforestation is reducing the amount of producers available
to take carbon dioxide out of the atmosphere by photosynthesis
■ This problem is exacerbated by the fact that in many areas of the
world, deforestation is taking place for land rather than for the trees
themselves, and as such they are burnt down, releasing yet more
carbon dioxide into the atmosphere
○
○ The importance of the carbon cycle
■ Carbon is a component of all organic molecules, many of which are
essential for life on earth, such as glucose
■ The Carbon cycle is a key process which allows the movement of
carbon between global reservoirs including the
a) Atmosphere
b) Biomass
c) Ocean
d) Soil
■ The balance of carbon between these reservoirs is fundamental
due to the role that carbon plays in sustaining life
a) If the balance is disrupted, somewhere along the way organisms
will suffer
By Chi Hoa, An Phong, Long
, b) Global warming is an large scale example of the effect which
may be seen if the global carbon balance is disrupted
○
○
III. 1.4 Climate change
- Climate change is the long-term pattern of temperatures, wind and rainfall on
Earth. The Earth’s climate has been very different in the past compared to
today.
- Effect of climate change : Extreme weather conditions, less predictable
rainfall, rising sea levels, increase in global temperature.
IV. 2.1 Atomic structure and the periodic table
● There are over 100 chemical elements which have been isolated and identified
● Elements are arranged on the periodic table in order of increasing atomic
number.
○ Each element has one proton more than the element preceding it
○ This is done so that elements end up in columns with other elements which
have similar properties
● The table is arranged in vertical columns called groups and in rows called
periods
○ Period: These are the horizontal rows that show the number of shells of
electrons an atom has and are numbered from 1 - 7
■ E.g. elements in period 2 have two electron shells, elements in period 3
have three electron shells.
○ Group: These are the vertical columns that show how many outer electrons
each atom has and are numbered from 1 – 7, with a final group called group 0
(instead of group 8)
By Chi Hoa, An Phong, Long
~NOTES FOR FINALS~
I. 1.1 1.2 Photosynthesis
● Photosynthesis is an endothermic reaction in which energy from sunlight is
transferred to the chloroplasts in green plants
○ Green plants use this energy to make the carbohydrate glucose from the raw
materials carbon dioxide and water
○ At the same time, oxygen is made and released as a waste product
● Photosynthesis can be defined as the process by which plants manufacture
carbohydrates from raw materials using energy from light.
● Photosynthesis can be summarised in a word equation as shown below:
●
● This equation can also be shown as a balanced chemical equation
○ Six carbon dioxide molecules combine with six water molecules to make one
glucose molecule and six oxygen molecules
●
○ The products of photosynthesis
■ Plants use the glucose they make as a source of energy in respiration
■ They can also use it to
By Chi Hoa, An Phong, Long
, ● Produce starch for storage
● Synthesise lipids for an energy source in seeds
● To form cellulose to make cell walls
● Produce amino acids (used to make proteins) when combined
with nitrogen and other mineral ions absorbed by roots.
●
II. 1.3 The carbon cycle
● Nutrients such as carbon and nitrogen are not endless resources, and so, they
need to be recycled in order to allow new organisms to be made and grow
○ Carbon is taken out of the atmosphere in the form of carbon dioxide by plants
to be used for photosynthesis
○ It is passed on to animals (and microorganisms) by feeding
○ It is returned to the atmosphere in the form of carbon dioxide by plants,
animals and microorganisms as a result of respiration
○ If animals and plants die in conditions where decomposing microorganisms
are not present the carbon in their bodies can be converted, over millions of
years and significant pressure, into fossil fuels.
○ When fossil fuels are burned (the process is known as combustion), the
carbon combines with oxygen and carbon dioxide is released into the
atmosphere
■ Increased use of fossil fuels is contributing to an increase in the
carbon dioxide content of the atmosphere
By Chi Hoa, An Phong, Long
, ○ In addition, mass deforestation is reducing the amount of producers available
to take carbon dioxide out of the atmosphere by photosynthesis
■ This problem is exacerbated by the fact that in many areas of the
world, deforestation is taking place for land rather than for the trees
themselves, and as such they are burnt down, releasing yet more
carbon dioxide into the atmosphere
○
○ The importance of the carbon cycle
■ Carbon is a component of all organic molecules, many of which are
essential for life on earth, such as glucose
■ The Carbon cycle is a key process which allows the movement of
carbon between global reservoirs including the
a) Atmosphere
b) Biomass
c) Ocean
d) Soil
■ The balance of carbon between these reservoirs is fundamental
due to the role that carbon plays in sustaining life
a) If the balance is disrupted, somewhere along the way organisms
will suffer
By Chi Hoa, An Phong, Long
, b) Global warming is an large scale example of the effect which
may be seen if the global carbon balance is disrupted
○
○
III. 1.4 Climate change
- Climate change is the long-term pattern of temperatures, wind and rainfall on
Earth. The Earth’s climate has been very different in the past compared to
today.
- Effect of climate change : Extreme weather conditions, less predictable
rainfall, rising sea levels, increase in global temperature.
IV. 2.1 Atomic structure and the periodic table
● There are over 100 chemical elements which have been isolated and identified
● Elements are arranged on the periodic table in order of increasing atomic
number.
○ Each element has one proton more than the element preceding it
○ This is done so that elements end up in columns with other elements which
have similar properties
● The table is arranged in vertical columns called groups and in rows called
periods
○ Period: These are the horizontal rows that show the number of shells of
electrons an atom has and are numbered from 1 - 7
■ E.g. elements in period 2 have two electron shells, elements in period 3
have three electron shells.
○ Group: These are the vertical columns that show how many outer electrons
each atom has and are numbered from 1 – 7, with a final group called group 0
(instead of group 8)
By Chi Hoa, An Phong, Long
