Photosynthesis Flashcards
(44 cards)
What is photosynthesis
An endothermic process used by plants to convert carbon dioxide and water into glucose and oxygen using energy in sunlight.
Word equation for photosynthesis
water + carbon dioxide → glucose + oxygen
Symbol equation for photosynthesis
6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂
What are chloroplast
An organelle that contains chlorophyll and in which photosynthesis takes place.
What are chlorophyll
Green pigment in plants that absorbs light energy used to carry out photosynthesis.
Endothermic
(absorbs heat)
A chemical reaction that requires a net input of energy
Adaptations of leaves for photosynthesis
Broad, thin, veins, cells packed with chloroplasts, waxy cuticle, stomata.
What are stomata?
Small openings on the underside of a leaf through which oxygen and carbon dioxide can move.
What are guard cells?
Cells that control the opening and closing of the stomata.
What are palisade mesophyll
Layer of cells packed with chloroplasts, where most photosynthesis occurs.
What are spongy mesophyll?
Layer of irregularly shaped cells with air spaces to allow gases to diffuse in and out of cells.
What are waxy cuticle?
A waterproof barrier that protects the leaf and prevents water loss.
What is gas exchange?
The transfer of gases between an organism and its environment
What is vascular bundle
Clusters of xylem and phloem tissue in stems.
What is Xylem
Tissue that transports water and dissolved minerals in vascular plants.
What are phloem?
Tissue that transports sugars in vascular plants.
Factors that affect the rate of photosynthesis
Light intensity
Temperature
Carbon dioxide
Chlorophyll
What is meant by ‘Limiting Factor’
A factor in short supply that prevents the rate of reaction from increasing.
Why carbon dioxide can be a limiting factor
Carbon dioxide is a raw material for photosynthesis.
Why light intensity can be a limiting factor
Light provides the energy that is needed for photosynthesis.
Why temperature is a limiting factor
If the temperature is too low the enzymes work slowly. If the temperature is too high the enzymes are denatured and do not work.
Why chlorophyll is a limiting factor
Chlorophyll is needed to absorb the light energy used to carry out photosynthesis
Importance of limiting factors
Farmers and commercial growers can artificially create the ideal environment to grow plants.
Five uses of glucose
For respiration Making cellulose Making amino acids Stored as oils or fats Stored as starch
