Topic 4 - Bioenergenics Flashcards
Label and state the functions the layers in the leaf
Palisade mesophyll- photosynthesis
Spongy mesophyll- diffusion of gases
Xylem- transport of water and minerals
Phloem- transport of sugars
Guard cells- open and close the stomata
Stomata- allow gas exchange and control water loss
Explain how the structures are adapted to their function
Palisade- contain many chloroplasts
Spongy- contains air spaces
Xylem- hollow tubes
Phloem- contains cell sap and pores at each end of cell
Guard cells- can change shape
What is meristem tissue?
Stem cells - undifferentiated plant cells
Where is the meristem tissue found?
The tips of roots and shoots
What is the word equation for photosynthesis ?
carbon dioxide + water –> glucose + oxygen
Write the balanced word equation for photosynthesis ?
6CO2 + 6H2O –> C6H12O6 + 6O2
Is photosynthesis endothermic or exothermic
Endothermic as it requires light energy
What do plants need for photosynthesis other than carbon dioxide and water
Chlorophyll and light
What are the 4 limiting factors of photosynthesis ?
Carbon dioxide concentration, light intensity, temperature, chlorophyll
What factors does a farmer need to consider when running a greenhouse ?
Maximising photosynthesis and therefore plant growth, but also maximising profit, so balancing spending on light and heat with the amount of crop produced.
What is the independent variable? (photosynthesis limiting factor practical)
Distance between lamp and pondweed (Light intensity)
What is the dependent variable? (photosynthesis limiting factor practical)
Number of bubbles per minute (rate of photosynthesis)
What are the control variables (photosynthesis limiting factor practical)
CO2 concentration, temperature, type of pondweed, length of pondweed
What is the pattern of the graph? (photosynthesis limiting factor practical)
As distance decreases, the number if bubbles produced per minute increases
Explain the pattern of the graph?(photosynthesis limiting factor practical)
As the lamp gets closes to the pondweed the light intensity increases. This increases the rate of photosynthesis, so more oxygen is produced.
What are the functions and adaptations of the xylem?
Transports water and minerals. Cells are strengthened by lignin join end to end to form a tube
What is transpiration?
Evaporation of water and loss through stomata of leaf
What are the 4 factors that affect transpiration rate?
Temperature, humidity, light intensity, air movement