Photosynthesis:
the process by which plants manufacture carbohydrates from raw materials using energy from light
Plants are known as
producers
plants make their own food
photosynthesis
Why do all living organisms need food
to grow and survive
Word equation photosynthesis
carbon dioxide + water → glucose + oxygen
Chemical equation photosynthesis
6CO2 + 6H20 = C6H12O6 + 602
Chlorophyll transfers
light energy into chemical energy in molecules, for the synthesis of carbohydrates
Chloroplasts contain
chlorophyll which absorbs sunlight (site of photosynthesis)
What is glucose stored as
starch
Chlorophyll
a green pigment that absorbs energy from the light
Light
provides energy
Water
absorb by the plant’s roots from the soil
Carbon dioxide
diffuses into the leaves from the air
Photosynthesis and light intensity
´As the amount of light increases, the rate of photosynthesis increases. The limiting factor is light. Increasing the amount of light after a certain point has no effect on the rate. The limiting factor is now carbon dioxide or temperature
Photosynthesis and carbon dioxide
´As the amount of carbon dioxide increases, the rate of photosynthesis increases. The limiting factor is Carbon dioxide. Increasing amount of Carbon dioxide after
a certain point has not effect on rate. The limiting factor is now light or temperature
Photosynthesis and temperature
´As temperature increases, the rate of photosynthesis increases until it reaches optimum temperature 40°C
The limiting factor is the temperature. Increasing the temperature above 40°C will cause the enzymes to denature This will decrease rate of photosynthesis
´Gas exchange is investigated using ____________________ solution which shows carbon dioxide concentration
hydrogen carbonate indicator
What is the top layer of the leaf?
waxy cuticle
What is the layer under the upper epidermis?
palisade layer
What is the layer under the palisade layer?
spongy mesophyll
What does the stomata do?
allows gas exchange
What do the xylem do?
transport water and minerals from the roots to the rest of the plant
What do the phloem do?
transports sugars and other molecules around the plant
What is the use of nitrate ions in a plant?
to make amino acids and proteins involved in growth
What indicates a nitrate ion deficiency?
stunned growth and older leaves turn yellow
What is the use of phosphate ions in a plant?
for DNA and cell membranes involved in respiration and growth
What indicates a phosphate ion deficiency?
older leaves turn purple and poor root growth
What is the use of potassium ions in a plant?
for enzymes involved in photosynthesis and respiration
What indicates a potassium ion deficiency?
poor fruit and flower growth and discoloured leaves
What is the use of magnesium ions in a plant?
making chlorophyll involved in photosynthesis
What indicates a magnesium ion deficiency?
small yellow leaves
What do root hair cells do?
help with water uptake
What is osmosis?
osmosis is the diffusion of water from an area of high water potential to an area of low water potential
What is a hypotonic solution?
Dilute: Low solute concentration, High water concentration
What is an isotonic solution?
Equilibrium: Same concentration of solute and water
What is a hypertonic solution?
Concentrated: High solute concentration, Low water concentration
Why do xylem vessels contain lignin?
So that the cells don’t burst
What is transpiration?
Transpiration is the evaporation of water at the surfaces of the spongy mesophyll cells in leaves, followed by loss of water vapour through the stomata.
What is translocation?
Translocation is the movement of sugar produced in photosynthesis to all other parts of the plant for respiration and other processes. This occurs in phloem cells.
Translocation occurs from _____ to _____
sources to sinks
What is the word equation for respiration?
Glucose + oxygen → carbon dioxide + water