B5. PLANT NUTRITION Flashcards
Write the word equation for photosynthesis.
chlorophyll
Carbon dioxide+water ——————> glucose + oxygen
light energy
Explain the importance of light in photosynthesis.
Without light, photosynthesis cannot take place in plant cells.
A. Write the balanced symbol equation for photosynthesis.
chlorophyll
6CO2 + 6H2O —————–> C6H12O6 + 6O2
light energy
chlorophyll
6CO2 + 6H2O —————–> C6H12O6 + 6O2
light energy
Annotate this equation to show where each of reactants come from and each of the products go to.
CO2 from air
H2O from soil water
C6H12O6 used in cells for respiration or converted to other chemical for use in cells
O2 released into air if not needed in respiration.
Explain why the transfer of energy from light to chemical energy in plant cells is essential for life on Earth.
Most organisms other than plants get their energy in chemical form from the food that they eat.
That energy was originally converted from light energy to chemical energy during photosynthesis in a plant cell and then transferred as chemical energy along the food chain.
Describe a test that would show the need for chlorophyll in photosynthesis.
Test the leaf of a variegated plant for starch.
Starch is only produced in the green parts of the leaf, where there is chlorophyll, so only the green parts of the leaf photosynthesis
What precautions should be taken when boiling ethanol to remove chlorophyll in a leaf? Explain your answer.
Heat in a water bath, keeping the ethanol away from open flames, such as from a Bunsen burner, because ethanol gives off flammables fumes.
Describe how Light intensity affects the rate of photosynthesis:
As light increases, so rate of the photosynthesis increases.
As light increases, more energy is supplied to drive the process of photosynthesis.
Describe how temperature affects the rate of photosynthesis:
As temperature increases, the rate of photosynthesis increases up to a maximum, after which it decreases rapidly.
b. As temperature increases, up to the maximum , the particles in the reaction including enzymes are moving faster and bump into each other more.
Above the maximum the rate of photosynthesis decreases because the enzymes that control the process start to become denatured.
Name five tissues in a leaf.
Cuticle Epidermis Spongy mesophyll Palisade mesophyll Xylem
List as many adaptations of a plant leaf for photosynthesis as you can.
Thin broad leaves
Chlorophyll in cells
Veins containing xylem tissue that transport water and mineral ion to the leaves and phloem tissue that takes product of photosynthesis to other parts of the plant
Transparent epidermal cells
Palisade cells tightly packed in a single layer near top of leaf
Stomata to allow gases into and out of leaf
Spongy mesophyll layer with large internal surface.
Explain why a large surface area inside the leaf is essential for photosynthesis.
A large surface area helps to maximize the rate of diffusion, in this case, the diffusion of carbon dioxide into cells for photosynthesis and oxygen out of cells so that it can be released into the air.
Explain why a transparent epidermis is an adaptation for photosynthesis.
It allows as much as light as possible to pass through the epidermal cells to reach the palisade cells below, where there are chlorophyll.
Explain why plants need a supply of mineral ions.
Plant make their own foods and need to convert the carbohydrates made by photosynthesis into other substances, such as proteins, which contain additional elements.
Explain plants use the Nitrogen ions for what
Nitrogen is an essential element for making substances other than carbohydrates, such as proteins.
