Chapter 6 Flashcards
photosynthesis
the process by which plants manufacture carbohydrates from raw materials using energy from light
State the word equation for photosynthesis
carbon dioxide + water → glucose + oxygen, in the presence of light and chlorophyll
State the balanced chemical equation for photosynthesis
6CO +6HO → C6H12O6 + 6O2
Explain chlorophyll and photosynthesis
Chloroplasts filled with chlorophyll use light energy that is converted into chemical energy, to drive the conversion of carbon dioxide and water from their environment into simple sugars (carbohydrates) which they use for their energy. In this process, the chemical energy is used to split water into hydrogen ions and oxygen. the hydrogen ions are then used to reduce CO2 into carbohydrates.
Outline the subsequent use and storage of the carbohydrates made in photosynthesis
Glucose made during photosynthesis is converted into starch/carbohydrates which is stored in leaves and other parts of the plant. The carbohydrates can be used in for photosynthesis in the future and as a structural component like cellulose in the wall. **
Investigate the necessity for chlorophyll, light and carbon dioxide for photosynthesis, using appropriate controls
3
Investigate and describe the effects of varying light intensity, carbon dioxide concentration and temperature on the rate of photosynthesis, e.g. in submerged aquatic plants
4
limiting factor
something present in the environment in such short supply that it restricts life processes
Identify and explain the limiting factors of photosynthesis in different environmental conditions
Light intensity (determines energy available during photosynthesis), temperature (influences activity of enzymes in the chloroplast) and carbon dioxide (raw material for photosynthesis). Light intensity may decrease in a dark room/forest, temperature can decrease during winter.
Describe the use of carbon dioxide enrichment, optimum light and optimum temperatures in glasshouses in temperate and tropical countries
Growers can pump CO2 into the greenhouse or burn butane or natural gas (can help to increase temp too!) to increase the CO2 concentration.
The glass lets in sunlight but artificial lighting can be used when light intensity is too low; blinds can also keep out very strong light and lowers temperature in the glasshouse.
Finally, sunlight can enter to heat the inside of the glasshouse, the glass stops a lot of the heat from leaving, electric heaters are used during winter and ventilator flaps are opened to keep it cooler.
Use hydrogen carbonate indicator solution to….
investigate the effect of gas exchange of an aquatic plant kept in the light and in the dark
Identify chloroplasts, cuticle, guard cells and stomata, upper and lower epidermis, palisade mesophyll, spongy mesophyll, vascular bundles, xylem and phloem in leaves of a dicotyledonous plant
just look online please
Explain how the internal structure of a leaf is adapted for photosynthesis
- there is a large surface area to absorb as many light rays as possible
- there is a thin shape so gasses can diffuse in and out easily
- there are many chloroplasts to absorb light for the reactions that take place in photosynthesis
- there are veins to support the leaf surface and to carry water and ions to the leaf cells and to take sucrose and amino acids away to the rest of the plant.
Describe the importance of nitrate and magnesium ions
nitrate ions make amino acids which are then used to make proteins. These proteins help with growth. Magnesium ions are absorbed by plants and used to make chlorophyll. This is needed for photosynthesis [phosphate is also needed to make DNA and for respiration]
Explain the effects of nitrate ion and magnesium ion deficiency on plant growth
If there is not enough nitrate ions in a plant, the plant is likely small and shows poor growth. If there is not enough magnesium, the plant may get chlorosis and their leaves would turn yellow. Making them useless for photosynthesis.
