Photosynthesis

Photosynthesis practical

Photosynthesis practical

1 Cut a 5cm piece of pondweed

2 Put the piece of pondweed in a boiling tube of

sodium hydrocarbonate to keep the concentration

of carbon dioxide the same

3 Put a light 5cm away from the pondweed

Count the number of bubbles produced in 2 mins

4. Repeat 3 times

5. Repeat for other distances = 10cm, 20cm, 30 cm,

40cm

6. Calculate a mean for each distance

Effect of exercise

1 Heart rate increases = more blood flowing to muscles so more oxygen and glucose delivered = faster rate of respiration = more energy.

2 Volume of blood per beat increases = same reason as above.

3 Breathing rate & volume increases = more air brought into body = more oxygen diffuses into the blood for aerobic respiration

4 Blood flow needs to increase to remove waste products such as carbon dioxide & bring back to lungs for diffusion.

Effect of temperature

1 As temperature increases, rate of photosynthesis increases, until it reaches the optimum temperature and then the rate decreases.

2 As temperature increases the particles have more kinetic energy so there are more successful collisions = faster rate of photosynthesis.

3 After the optimum temp, the chlorophyll (enzyme) denatures, so the rate of photosynthesis decreases.

What does plant use glucose for?

1 Used in respiration

2 Stored as starch

3 Stored as fats and oils

4 Makes cell walls (cellulose)

5 Makes amino acids which are turned into proteins.

6 All of the above (except respiration) = growth.