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Biology {Respiration & Photosynthesis Summer} :croissant: - Coggle…
Biology {Respiration & Photosynthesis Summer} :croissant:
Respiration
aerobic respiration
Word Equation
glucose + oxygen ---> water + carbon dioxide + ATP
Chemical Equation
C6H12O6 + 6O2 ---> 6CO2 + 6H2O + 38 ATP
anareobic respiration
muscle cell- glucose -> lactic acid
yeast cell- glucose-> ethanol + carbon dioxide
consequences of reducing
blood flow in any part of body
if heart- heart attack
oxygen not getting to cells-> reduces aerobic respiration
less energy-> respire anaerobically-> produces lactic acid
lactic acid -> changes pH-> enzymes denature
Photosynthesis
Word Equation
water + carbon dioxide ---> glucose + oxygen
Chemical Equation
6H2O + 6CO2 ---> C6H12O6 + 6O2
photosynthesis is an endothermic reaction where light energy is converted into chemical energy
Limiting Factors affecting Photosynthesis
carbon dioxide concentration-
as CO2 concentration increases the rate of photosynthesis increases
light intensity-
: as light intensity increases so does the rate of photosynthesis.
temperature-
as temperature increases so does the rate of photosynthesis up until the optimum temperature for enzymes. If too hot, the enzymes denature. If too cold, there is not enough kinetic energy for enzymes to collide and make enzyme-substrate complexes.
Structure of the Leaf
waxy cuticle
protective layer on top of leaf helps to reduce water loss by evaporation
upper epidermis
thin and transparent so light can pass to palisade mesophyll
palisade mesophyll
lots of chloroplasts for rapid photosynthesis, aligned vertically, densely packed
spongy mesophyll
lots of air spaces to allow gases to diffuse in and out faster as it increases the surface area:volume
lower epidermis
contains guard cells and stomata (gaps)
guard cells
kidney-shaped cells that open and close based on absorbing and losing water (when there is lots of water the cells fill and open the stomata)
stomata
opens every day and closes at night where gas exchange occurs as wells as evaporartion
flat and wide
large surface area for sunlight to hit
thin
short diffusion distance
xylem vessels
deliver water to leaf cells for photosynthesis
Investigate the evolution of CO2 from respiring seeds
1) Pour some sodium hydroxide in the first conical flask to remove the carbon dioxide.
2) Pour some hydrogen carbonate indicator into 3 tubes and lay out moist cotton wool.
3) Place 10 respiring seeds into tube A. Place 10 dead/boiled seeds into tube B. Place 10 glass beads into tube C.
4) After 3 hours, observe the colour of the indicator.
Respiring seeds= yellow (CO2 being produced) Glass beads/dead seeds= orange (same conditions-no CO2 produced)
Mineral Ions needed for Plants
Nitrates
(make proteins for growth)
deficiency slow growth, leaves die
Magnesium
(produce chlorophyll)
deficiency yellow leaves
Phosphates
(make DNA, root growth)
deficiency purple leaves, wilted roots
Potassium
(produces energy ATP)
deficiency dead spots
Investigate the evolution of heat from respiring seeds
1) Set up to thermoflasks. 2) Place respiring seeds with moist cotton in one flask and do the same in the other but with dead seeds as a control. 3) Record the initial temperature with the thermometer.4) After 4 days, measure the final temperature and calculate the temperature difference.
DORIC
D:colour of hydrogen carbonate indicator (CO2 concentration) O: respiring seeds R: I: the seeds placed in the flasks. C: amount of dead seeds. glass beads, concentration and volume of sodium hydroxide and hydrogen carbonate indicator
Investigate photosynthesis, showing the evolution of oxygen from a water plant, and the requirements of light/CO2*
1) Fill the boiling tube with sodium hydroxide solution.
2)Place the cut pond weed into the boiling tube.
3) Place the test tube rack 10 cm away from a LED lights.
4) Leave for 5 mins.
5) Start the stop watch and count bubbles produced per minute
6) Test this twice to get a mean.
7) Repeat these steps with different distances.
7) Repeat these steps with different concentrations of sodium hydroxide solution.
8) Plot a graph of the rate of photosynthesis( given by the no. of bubbles) against light intensity/ CO2 concentration.
DORIC
D: no. of bubbles O: pondweed R: 3 times I: light intensity/Co2 concentration C: species of pondweed, temperature, volume of solution, time for counting bubbles.species of plant (amount of leaves)
Investigate photosynthesis, showing the production of starch and the requirements of chlorophyll
1) Use a variegated leaf (with white and green parts)
2) Boil the leaf to denature enzymes.
3) (alternative) boil leaf in ethanol to get rid of chlorophyll dip leaf in water to hydrate for iodine
4) Spread onto white tile to see colour change.
5)Use a dropping pipette and add iodine solution
6)Green parts of leaf will turn blue-black and white parts will stay yellow/brown.
Safety
turn off Bunsen burner before using ethanol (it is flammable), wear goggles as it can protect from eyes from chemicals, use tongs-> avoid burns.
To test factors affect on starch production:
light
cover one part of the leaf with foil and leave the other exposed.
chlorophyll
use a variegated leaf/ boil one leaf with ethanol and not another.
carbon dioxide
seal a bag with sodium hydroxide around a leaf attached to the plant to remove CO2 and compare
Impact of very high temperatures on plant growth
more transpiration (water loss)
loss of water -> wilting-> stomata close-> less CO2
active site loses shape-> enzymes denature
Conclusion:
plant growth reduces because rate of photosynthesis reduces
polythene bag around pot of soil
stop water from evaporating from the soil to measure transpiration accurately
stop carbon dioxide from being released from respiring micro organisms in soil