Topic 4: Bioenergetics Flashcards
What is the equation for Photosynthesis?
Carbon Dioxide + Water –> Glucose + Oxygen
What is the balanced symbol equation for photosynthesis?
6 CO2 + 6H2O –> C6H12O6 + 6O2
What is an exothermic reaction?
Releases energy into surroundings
What is an endothermic reaction?
Takes in energy from surroundings
What type of reaction is photosynthesi?
Endothermic
What is glucose used for in respiration?
Provide energy
Where is light energy provided for photosynthesis?
Absorbed by chlorophyll
Where is water provided for photosynthesis?
Taken into roots by osmosis
Where is carbon dioxide provided for photosynthesis?
Enters leave in diffusion through stomata
Where is oxygen provided for respiration?
Leaves through diffusion by stomata in leaves
What is the inverse square law?
Light Intensity = 1/d^2
Less photons per mm so light intensity decreases as area increases
What are the uses of glucose?
- Respiration
- Converted into insoluble starch for storage
- Used to produce fat or oil for storage
- Used to produce cellulose, strengthens cell wall
- Used to produce amino acids for protein synthesis
- Control of osmosis
- Growth
- Make larger molecules
What are the limiting factors for photosynthesis?
- Temperature
- CO2 Concentration
-Light Intensity - Number of chlorophyll
- Volume of Water *only use if necessary
Why are limiting factors important?
Important in the economics of enhancing the conditions in greenhouses to gain the maximum rate of photosynthesis whilst maintaining profit
How can you read graphs and locate limiting factors?
The rate of photosynthesis will increase as limiting factor increases but will level out at point another factor prevents further increase of photosynthesis
Check flashcards for graphs
How can you read a temperature graph in relation to rate of photosynthesis?
The rate of photosynthesis will increase as temp. increases until optimum temp. is reached. The rate will then decreased as temp. increase further. This is because enzyme would have denatured.
Check flashcards for graphs
What is the starch food test?
- Food on white dimple tile
- Few drops of iodine solution
- Note colour change
- Starch turns iodine blue - black
What is the glucose food test?
- Grind food in pestle and mortar
- Two spatulas in test tube
- 1cm^3 of distilled water
- 10 drops of Benedict’s
- 80°C Water Bath for 5 minutes
- Turns brick red if present but varies due to sugar concentration
What is the protein food test?
- Grind food in pestle and mortar
- Two spatulas in test tube
- 1cm^3 of distilled water
- 10 drops of Biuret’s and Sodium Hydroxide
- Shake
- Protein turns purple
What are guard cells?
Use osmotic pressure to open and close stomata, allowing plants to regulate water ( prevent water loss ) and facilitate gas exchange necessary for photosynthesis
What are palisade cells?
Receive most sunlight for the production of glucose and oxygen in photosynthesis, contain most chloroplasts and are closely packed together to increase rate of absorption
What is the independent variable?
Variable which is altered
What is the dependent variable?
Variable being tested for
What is the control variable?
Variable being maintainedWhat
