science 2 Flashcards
(21 cards)
What is photosynthesis?
A chemical reaction where light and chlorophyll convert CO2 and H2O into O2 and glucose
Photosynthesis is essential for plants to produce their own food.
Where does photosynthesis occur?
In the chloroplasts of green plant cells, usually in leaves
Chloroplasts contain chlorophyll, which is vital for photosynthesis.
What is the word equation for photosynthesis?
Carbon dioxide + Water → Oxygen + Glucose
What is the balanced chemical symbol equation for photosynthesis?
6CO2 + 6H2O → 6O2 + C6H12O6
What is the role of chlorophyll in photosynthesis?
To absorb light energy for the reaction
Chlorophyll is the green pigment found in chloroplasts.
Why is photosynthesis important?
It allows plants to produce glucose for respiration, which provides energy to grow, repair, and reproduce
What are the limiting factors that affect the rate of photosynthesis?
- Temperature
- Light intensity
- Carbon dioxide concentration
How does temperature affect the rate of photosynthesis?
Enzymes control photosynthesis and need to work at an optimum temperature; the rate increases until the optimum temperature, then decreases
How does light intensity affect the rate of photosynthesis?
The rate increases with more light intensity until it levels off when light intensity is no longer a limiting factor
How does carbon dioxide concentration affect the rate of photosynthesis?
The rate increases with higher CO2 concentration until it levels off when concentration is no longer a limiting factor
What happens to the rate of photosynthesis at high altitudes?
It may be low due to cold temperatures
What is diffusion?
Movement of particles from high to low concentration across a semi-permeable membrane
What is the function of mitochondria?
Respiration, release of energy
What is the perfect state of plant cells?
Turgid
What happens if too much water enters an animal cell?
It bursts
What is osmosis?
Movement of water from high water potential to low water potential through a semi-permeable membrane
True or False: Plant cell walls are made of chitin.
False, they are made of cellulose
Give an example of a specialised cell in animals.
- Sperm cells
- Egg cells
- Neurons
What happens if too much water leaves a plant cell?
It is plasmolysed
What is active transport?
Movement of particles from low to high concentration across a semi-permeable membrane, requiring energy
