Question

please graph this and answer the 2 questions below

etrum Graph of Spinach Chloroplast Extract 0.41 sle 1: Effect of Light Intensity on the Rate of Photosynthesis (Time should be in minutes, not minutes & seconds) Light Elapsed time Elapsed time Rate of Photosynthesis Intensity (minutes seconds) (minutes) ml. o (ml /hour) 45 watts 25 min 15 sec 25.25min 0.1 0.24 75 watts 14 min 45 sec 14.75 min 0.1 150 watts 16 min 30 sec 16.5min 0.1 0.36 Calculating the Rate of Photosynthesis: The procedure is much the same as the one you used to calculate the metabolic rate. Divide the mL O, released (0.1 ml) by number of minutes (elapsed time) it took, then multiply that by 60 minutes/hour, as shown in this example: 0.1 mL oxgyen 60 minutes X = 0.75 ml/hour 8 minutes 1 hour Plot the rate data on the graph below: Questions: 1. Is the relationship between the intensity of light and the rate of photosynthesis a direct or an inverse relationship? 2. Would you expect the rate of photosynthesis to increase indefinitely with increasing light intensity? Explain why or why not.

use the data above to plot a graph of light intensity versus rate of photosynthesis.

Answer 1

Answer-

According to the given question-

We know that during photosynthesis, the plant made its own food in the form of sugar, by taking water, and carbon dioxide in the presence of sunlight.

Here we can observe the rate of photosynthesis in a Plant.

Light Intensity (Watt)	Rate of photosynthesis ml. O2 / hour
0	0
45	0.2376
75	0.406
150	0.363

Rate of photosynthesis ml. 02 /hour 0.45 0.4 0.35 Rate of photosynthesis Oml. 02 /hour 0.3 0.25 0.2 0.15 Rate of photosynthesis ml. 02 /hour 0.1 0.05 0 0 200 50 100 150 Light Intensity (Watt)

A – Here we can observe that the rate of photosynthesis is increasing on increasing the intensity of light, thus follow direct relationship.

B – The rate of photosynthesis depends upon several factors such as-

• The intensity of light.
• Level of carbon dioxide or concentration of carbon dioxide
• Temperature

So on increasing the intensity of light itself does not increase the rate of photosynthesis, because other factors may be limited or become short during photosynthesis.

As we can observe from the graph that on increasing the intensity of light more than 75 watts, and also for a longer duration of time, the rate of photosynthesis decreases, because of short supply of limiting factor or the pigment present in the plant unable to absorb the light. so the rate of photosynthesis will not increase indefinitely on increasing the intensity of light.