28) the graph below shows how the activity of an enzyme changes at different temperatures.
which statement best describes what happens to the enzyme when the temperature of the
reaction increases to 63°c?
enzyma activity vs. temperature
enzyme activity
increasing
0
10

20 30 40 50 60 70
temperature (°c)
a) the enzyme is used up and the reaction stops.
b) the enzyme begins to decrease the rate of the reaction.
(c) the enzyme continues to increase the rate of the reaction.
d) the enzyme changes shape and can no longer speed up the reaction.

d) The enzyme changes shape and can no longer speed up the reaction

Explanation:

Enzymes aare protein in nature therefore sensitive to changes in temperature. Most enzymes have an optimum temperature ranging from 35-40°c. As the temperature increases, optimum temperature is reached where the rate of reaction is maximum. Temperatures above 40-63°c denatures the enzymes making them non effective thus the reaction decreases sharply.

a. Photosynthesis

b. Oxygen

c. Light from the lamp

Explanation:

a. The process that is occurring in the plant's cell to produce the gas in the bubble is photosynthesis. The process involves the use of inorganic substances such as carbon dioxide and water in the presence of light to manufacture carbohydrates. Oxygen is evolved in the process. The equation for the process is as below:

b. The gas produced by the plant is oxygen as shown in the equation above.

c. The source of energy the plant is using to conduct the process is the light from the lamp. Light catalyzes the excitation of photosystems, causing the release of electrons that causes the splitting of water.