Photosynthesis Flashcards
(28 cards)
What is photosynthesis?
Photosynthesis is the process by which leaves absorb light and carbon dioxide to produce carbohydrate (food) for plants to grow.
What is the equation for photosynthesis?
light
carbon dioxide + water —–> glucose + oxygen
Why are plants green?
Plants are green because of the green pigments chlorophyll inside the chloroplasts in their cells.
Why do leaves have a large surface area?
Leaves have a large surface area to absorb more light.
Why are leaves thin?
Leaves are thin so there is a short distance for carbon dioxide to diffuse into leaf cells.
Why do leaves have chlorophyll?
Leaves have chlorophyll to absorb sunlight to transfer energy into chemicals.
Why is there a network of veins?
To support the leaf and transport water and carbohydrates.
Why do leaves have stomata?
Leaves have stomata to allow carbon dioxide to diffuse into the leaf.
Why in leaves is the epidermis is thin and transparent?
To allow more light to reach the palisade cells.
Why in leaves is the thin cuticle made of wax?
To protect the leaf without blocking out light.
Why in leaves is the palisade cell layer at top of leaf?
To absorb more light.
Why is there a spongy layer in leaves?
Air spaces allow carbon dioxide to diffuse through the leaf, and increase the surface area.
Why in leaves do palisade cells contain many chloroplasts?
To absorb all the available light.
What are the possible factors that can affect photosynthesis?
- Temperature
- Light intensity
- Carbon dioxide
- Water
What can farmers do to maximize growth?
Farmers can use their knowledge of these limiting factors to increase crop growth in greenhouses. They may use artificial light so that photosynthesis can continue beyond daylight hours, or in a higher-than-normal light intensity. The use of paraffin lamps inside a greenhouse increases the rate of photosynthesis because the burning paraffin produces carbon dioxide, and heat too.
What is transpiration?
Water evaporates from the stomata in a process called transpiration.
What happens to the rate of photosynthesis with a higher temperature used?
The higher the temperature, the faster the rate of photosynthesis and the faster the production of materials that enable plants to grow.
What happens if the temperature continues to increase beyond an optimum?
If the temperature continues to increase beyond an optimum, photosynthesis slows down because the enzymes controlling the different reactions of photosynthesis have become denatured.
What is xylem tissue?
Xylem tissue consists of columns of hollow, dead cells. It carries water and dissolved mineral salts from the roots, through the stem and out into every leaf and flower.
What is phloem tissue?
Phloem tissue runs by the side of the xylem. Its tube-like cells carry dissolved glucose and other substances to all parts of the plant.
What is the transpiration stream/
As more water is lost from the leaves, more is drawn up through the xylem tissue from the roots, which absorbs more water from the soil. This continuous movement of water is called the transpiration stream.
What is osmosis?
Osmosis is the movement of water from high water concentration to a lower one across a partially permeable membrane.
How do cells become flaccid (limp)?
Cells left in a concentrated salt or sugar solution will lose water by osmosis and become flaccid.
What are root hair cells?
Root hair cells are fine, hair-like extensions of a root.
