Photosynthesis And Cell Respiration

Front 1

Define cell respiration

Back 1

• Cell respiration is the controlled release of energy from organic compounds in cells to form ATP. ATP is the molecule which directly fuels the majority of biological reactions.
• Equation: 6CO2 + 6H2O + energy --> 6O2 + C6H12O6

Front 2

State that in cell respiration, glucose in the cytoplasm is broken down by glycolysis into pyruvate, with a small yield of ATP.

Back 2

• In cell respiration, glucose in the cytoplasm is broken down in a process called glycolysis into pyruvate with a small yield of ATP. The product is 2 pyruvate and a small amount of ATP. Glycolysis does not use oxygen.

Front 3

Explain that, during anaerobic cell respiration, pyruvate can be converted in the cytoplasm into lactate, or ethanol and carbon dioxide, with no further yield of ATP.

Back 3

In anaerobic cell respiration the pyruvate stays in the cytoplasm and in humans is converted into lactate which is then removed from the cell. In yeast the pyruvate is converted into carbon dioxide and ethanol. In either case, no ATP is produced.

Front 4

Humans anaerobic respiration

Back 4

• Location: cytoplasm
• Substrate: Glucose
• Product: Lactic acid (lactate) + ATP
• Note: Lactic anaerobic respiration supplements aerobic respiration in the production of ATP. Both aerobic and anaerobic respiration can take place in the human cell at the same time

Front 5

Yeast anaerobic respiration

Back 5

• Location: cytoplasm
• Substrate: Glucose
• Product: Ethanol + carbon dioxide + ATP
• This is the end point for this fermentation reaction. Ethanol and CO2 are both excreted with no further metabolism of the energy stored in the ethanol (very inefficient)
• Note: The glucose molecule has been hydrolysed further than in the human respirtion. Some organisms are totally anaerobic others can switch between anaerobic and aerobic

Front 6

Anaerobic respiration

Back 6

• Fermentation respiration in yeast yields two useful products from a human perspective. The carbon dioxide can be used in a variety industrial processes the best known of which is to raise bread. Many brewers of alcohol will bottle the CO2 for use in the ‘carbonation’ of other drink products.
• The alcohol itself is of course the basis of many industries such as beer brewing. In more recent time the use of fermentation products is being used as an alternative source of fuel such as is the case in the fuel for automobiles

Front 7

Explain that, during aerobic cell respiration, pyruvate can be broken down in the mitochondrion into carbon dioxide and water with a large yield of ATP

Back 7

• If oxygen is available, the pyruvate is taken up into the mitochondria and is broken down into carbon dioxide and water. A large amount of ATP is released during this process.

Front 8

State that photosynthesis involves the conversion of light energy into chemical energy

Back 8

• Photosynthesis involves the conversion of light energy into chemical energy
• Location: Chloroplasts
• Reaction: Traps light energy and converts it into chemical energy
• Organisms: Prokaryotic and Eukaryotic
• Substrate: Inorganic CO2 and H2O
• Products: Organic compounds (sugars) and oxygen
• Equation: 6CO2 + 6H2O --> 6O2 + C6H12O6

Front 9

State that light from the sun is composed of a range of wavelengths

Back 9

• Light from the sun is composed of a range of wavelengths. Combined, the wavelengths give the white light we associate with full sunlight. The shortest wavelengths are the blues which have more energy. The longer wavelengths are the reds which have less energy.

Front 10

State that chlorophyll is the main photosynthetic pigment

Back 10

• Chlorophyll is the main photosynthetic pigment. This is where the light energy is trapped and turned into chemical energy.

Front 11

Outline the differences in absorption of red, blue and green light by chlorophyll

Back 11

• The main colour of light absorbed by chlorophyll is red and blue. Chlorophyll cannot absorb green light and so instead it reflects it making leaves look green.

Front 12

State that light energy is used to produce ATP and to split water molecules (photolysis) to form oxygen and hydrogen.

Back 12

Chemical energy absorbed by chlorophyll is trapped in making ATP

Front 13

Photolysis

Back 13

Water used in photosynthesis is split and provides: C2H12O6 & Oxygen

Front 14

State that ATP and hydrogen (derived from the photolysis of water) are used to fix carbon dioxide to make organic molecules

Back 14

• H+ from splitting of water are combined with carbon dioxide to form organic compounds (e.g. sugar)
• Bonds are formed between carbon, hydrogen and oxygen in using energy from ATP
• Carbon, hydrogen and oxygen are enough to form lipids and carbohydrates

Front 15

3.8.8 .7

Back 15

LOOK ON WORD DOC

Front 16

Temperature (affect the distribution of plant species)

Back 16

Warmer temperature allows photosynthesis and other metabolic reactions to take place at a faster rate. Cold temperatures reverse this, freezing prevents transpiration and photosynthesis and may cause tissue damage. Very hot conditions may lead to dessication (extreme dryness).

Front 17

Water (affect the distribution of plant species)

Back 17

Water is a raw material for photosynthesis and therefore essential for plant growth. Water is needed to maintain turgor pressure in the cells and therefore support the plant.

Front 18

Light (affect the distribution of plant species)

Back 18

The availability of light links directly to plant photosynthesis and ecosystem productivity. Dark areas have small number of plants.

Front 19

Soil pH(affect the distribution of plant specie)

Back 19

Soil pH is important for the absorption of nutrients. If the soil is acidic, desertification can occur (fertile land becomes desert).
o Example: Calciguge such as heathers cannot grow on chalk or limestone but thrive on acid moorland.
o Calcicole – plants that thrive on chalk or limestone is intolerant of the higher levels of Aliminium ions found in acid soils.

Front 20

Salinity (affect the distribution of plant specie)

Back 20

Salinity has an effect on the absorption through osmosis. High salt levels can cause damage to the leaves of the plants as water is extracted due to osmosis.

Front 21

Mineral nutrients (affect the distribution of plant specie)

Back 21

Mineral nutrients are needed for vital functions. Nitrogen is needed to manufacture proteins, enzymes, nucleotides, vitamins, and other compounds. Phosphorous is used in the formation of phospholipids and other structures. Low levels of nutrients are found in some chalk grasslands and in wet areas (swamps, moorlands, etc) due to action of denitrifying bacteria.