Practical - Light Intensity and Photosynthesis Rate

The video tutorial explains an experiment to study how light intensity affects the rate of photosynthesis in pondweed. It covers the setup, including the use of a lamp and hydrogen carbonate solution, and details the independent, dependent, and control variables. The procedure involves measuring oxygen bubbles produced at varying distances from the light source. Results are recorded in a tally chart and analyzed using a scatter graph, showing that increased distance (decreased light intensity) reduces photosynthesis rate.

What is the primary purpose of the photosynthesis experiment described?

• To find the optimal temperature for photosynthesis

• To determine the best type of pondweed for photosynthesis

• To investigate the effect of light intensity on photosynthesis rate

• To measure the amount of glucose produced

Which component in the experiment provides carbon dioxide to the pondweed?

• The hydrogen carbonate solution

• The boiling tube

• The beaker of water

• The lamp

What is the independent variable in the photosynthesis experiment?

• The type of pondweed used

• The distance of the pondweed from the lamp

• The temperature of the water

• The number of bubbles produced

Why is the pondweed placed in bright light for two hours before the experiment?

• To ensure it is healthy

• To bring the rate of photosynthesis to a steady value

• To dry the pondweed

• To change its color

How is the average number of bubbles produced calculated?

• By subtracting the bubbles in the second attempt from the first

• By multiplying the number of bubbles by the distance

• By adding the total number of bubbles from two attempts and dividing by two

• By counting the bubbles in one attempt

What type of graph is used to represent the experiment's results?

• Pie chart

• Line graph

• Bar graph

• Scatter graph

What conclusion can be drawn from the experiment regarding light intensity and photosynthesis?

• As light intensity increases, the rate of photosynthesis decreases

• As light intensity decreases, the rate of photosynthesis decreases

• As light intensity decreases, the rate of photosynthesis increases

• Light intensity has no effect on the rate of photosynthesis