1530798
| Question | Answer |
| What is photosynthesis? | The process by which plants make food. Light energy is converted to chemical energy by the process of photosynthesis. |
| Word and chemical equation for photosynthesis |
Image:
photosynthesis (image/jpg)
|
| What is the rate of photosynthesis affected by? | Carbon dioxide concentration Light intensity Temperature |
| The leaves of plants make ............. from carbon dioxide and water using .............. energy from the ......... . This energy is captured by .................. in the ...................... of the leaves and converted to chemical energy in the glucose. ....................... is also produced as a waste product. Glucose is converted into ............... to be transported around the plant and into ............... to be stored. | glucose light sun chlorophyll chloroplasts Oxygen sucrose starch |
| Glucose made in photosynthesis is used to make: ............ for transport ............ for storage .................... for cell walls, proteins & DNA ........... as an energy store in seeds ............... | Sucrose Starch Cellulose Lipids Chlorophyll |
| Name some adaptions plant leaves have to make photosynthesis as efficient as possible. | Thin and flat - as much light absorbed as possible Distances that gases need to diffuse it very short |
| Draw the structure of a leaf |
Image:
leaf (image/jpg)
|
| Why do the levels of CO2 around a plant vary during the day? | Plants respire all the time using oxygen and carbon dioxide. During the night they can't photosynthesis as there is no light so they are producing carbon dioxide. However during the day, when there is lots of light, plants carry out more photosynthesis than respiration so more oxygen is released than CO2. |
| What is a limiting factor? | A component of a reaction that is in short supply so limits the rate at which a reaction can take place |
| What are the limiting factors for photosynthesis? | Light intensity Concentration of CO2 Temperature |
| Draw a graph to show the effect of limiting factors on the rate of photosynthesis. |
Image:
axis (image/jpg)
|
| How do plants get the minerals they need? Which minerals do they need and why? | From the soil, using active transport nitrates- make amino acids which are built up into proteins Magnesium- make chlorophyll |
| What is osmosis? | The movement of water down a concentration gradients of water through a partially permeable membrane |
| Plant cells need to be ........... to support the plant. Water moves into and out of living cells by ................ . | Turgid osmosis |
| Water is taken up from the soil by the ......... ............ cells and moves across the root by ............. . Water and mineral ions are transported around the plant in the ............. . Sucrose and amino acids are transported around the plant by the ................... . | root hair osmosis xylem phloem |
| What is transpiration? What factors affect the rate of transpiration? | The evaporation of water from the surface of a plant Humidity, wind speed, temperature, light intensity |
| Explain why osmosis is very important in plant cells. | Water moves into the plant cell by osmosis. The vacuole and cell swell up and the cytoplasm pushes against the cell wall. The plant cell is turgid. This turgor pressure is very important for plant cells to be able to support the structure of the plant. |
| What happens if plant cells are placed in a solution more concentration than the cell contents? | Water moves out of the cell by osmosis. The cell decreases in volume and the cytoplasm no longer pushes against the cell wall. The cell is flaccid. If the water loss by osmosis continues the cytoplasm shrinks right away from the ell wall and cause the plant cells to be plasmolysed. It cannot support the plant tissues and plant wilts. |
| What affect does wilting have? | Helps protect the plant from further water loss |
| Plants have two types of transport tissue (............. .............) which carry material around the plant. Name them both, what they are made from and their role. | vascular tissue Xylem- made of cell walls of dead cells. Transports water and mineral ions from the roots to the rest of the plant. Phloem- made of living cells. Transports sugars for energy and amino acids for cell building all around the plant. |
| How do plants uptake water? | Outsides of roots covered in root hair cells- Increase surface area. Concentration of water is much lower in the root cell cytoplasm so water moves in by osmosis. Moves across root cells to the xylem along concentration gradient by osmosis. |
| How do plants uptake minerals? | Mineral ions are in low concentration in the soil. They are moved into the root hair cells by active transport, using the energy from cell respiration. Once inside the root they move across the root mainly by diffusion and enter the xylem vessels. |
| Explain the transpiration stream. | Water leaves the leaf as water vapour through the stomata. Evaporate from the mesophyll, cooling leaf. Water moves from xylem to mesophyll cells because the cytoplasm has become more concentrated by osmosis. This effectively 'pull' water up the xylem. The continuous flow of water is known as the transpiration stream. |
| What is the rate of transpiration controlled by? | stomata- found on underside of the leaf to reduce water loss. They open and close to allow gas exchange and to control the rate of water loss. |
| Explain how to measure the rate of transpiration. |
Measure how far the air bubble has moved Change the light intensity, air flow, temperature etc. you can measure the effect on transpiration.
Image:
potometer (image/jpg)
|
Want to create your own Flashcards for free with GoConqr? Learn more.