Nutrition (Flowering plants) Flashcards
Which type of energy becomes which in photosynthesis?
Light energy becomes chemical energy
What is the word equation for photosynthesis?
Carbon Dioxide + Water –> Glucose + Oxygen
The glucose can be used in a variety of ways, like cellular respiration, producing starch for storage, forming cellulose and synthesising lipids and amino acids when mixed with nitrogen
What is the balanced chemical symbol equation for photosynthesis?
6CO₂+6H₂O –> C₆H₁₂O₆+6O₂
What are the three main factors affecting the rate of photosynthesis?
- Carbon dioxide concentration
- Temperature
- Light intensity
Chrorophyll concentration/amount can also be a factor
Note that these are all limiting factors, and will only affect the rate of photosynthesis up to a certain point before another factor limits its further increases
How does temperature affect the rate of photosynthesis?
It increases the amount of kinetic energy particles will have, increasing the rate of photosynthesis as more collisions occur
What happens to the rate of photosynthesis at low temperatures?
The rate of photosynthesis is slow as particles have little kinetic energy and few collisions will happen
What happens to the rate of photosynthesis when the temperature is increased to the optimum level?
The rate of photosynthesis increases as the particles have the most kinetic energy without the enzymes involved denaturing
What happens to the rate of photosynthesis when the temperature is increased too much?
- The rate of photosynthesis steeply decreases
- This is because: The enzymes denature, the plant loses water faster (rate of transpiration), and the stomata will close to conserve water so less carbon dioxide will be absorbed
How does light intensity affect the rate of photosynthesis?
The higher the light intensity, the higher the rate of photosynthesis as the plant is receiving more light. It will only stop increasing when there is another limiting factor
How does carbon dioxide concentration affect the rate of photosynthesis?
The higher the carbon dioxide concentration, the higher the rate of photosynthesis as the plant is receiving more carbon dioxide. It will only stop increasing when there is another limiting factor
How does chlorophyll concentration affect the rate of photosynthesis?
The higher the chlorophyll concentration, the higher the rate of photosynthesis as the plant has more chlorophyll to undergo photosynthesis with. It will only stop increasing when there is another limiting factor
What are all of the structures found in a leaf from top to bottom?
- Waxy cuticle
- Upper epidermis
- Palisade mesophyll
- Spongy Mesophyll
- Lower Epidermis
- Stomata
- Guard Cells
- Vascular Bundle (in spongy mesophyll)
How is the structure of a leaf adapted for photosynthesis?
- The leaf is thin to achieve a large surface area to volume ratio to maximise gas exchange and light absorbtion
- Upper epidermis is thin and transparent to let light through to the palisade mesophyll
- Layer of palisade cells with tightly packed chloroplasts to maximise light absorbtion and photosynthesis
- Air spaces in the spongy mesophyll allow for gas exchange of carbon dioxide and oxygen and increase surface area
- Stomata in lower epidermis allow gas exchange between oxygen and carbon dioxide to happen
- A vascular bundle of xylem and phloem which allow the transport of water to the leaf and glucose from the leaf
Make sure you apply all of these things directly to photosynthesis
Which two mineral ions do plants require for growth and photosynthesis?
Magnesium and Nitrate Ions
How do plants absorb mineral ions?
Through the soil by root hair cells via active transport or diffusion
