The statement Bonds in the hydrogen peroxide are weakened in catalase's active site, allowing the chemical reaction to occur is the answer. Catalase is an enzyme in the liver that breaks down harmful hydrogen peroxide into oxygen and water.
Answer:
Over 95% of incoming ultraviolet radiation is absorbed in :
A. The Stratosphere.
Explanation:
- Stratosphere is the second layer of the earth's atmosphere that lies next to the troposphere.
- This layer experiences very little turbulence of air and is very significant because of the presence of Ozone layer in it.
- The UV rays entering the Earth's atmosphere, photo dissociates ozone into O₂ and O. But these molecules quickly recombine to form ozone.Thus, stabilizing the concentration of ozone in the atmosphere.
- During this photo dissociation UV radiations loses much of its energy. Thus, 95% of incoming Ultraviolet radiation gets absorbed in the Stratosphere.
- Absorption of ozone UV radiation increases exponentially with the thickness of ozone layer.
The correct answer is option C, that is, regulate water loss.
Guard cells refer to the cells enclosing each stomata. They assist in monitoring the rate of transpiration by closing and opening the stomata. The guard cells possess the tendency to monitor the closing and opening of stomata by changing shape. The shape of the guard cells modifies on the basis of the concentration of potassium ions and water found in the cells themselves.
The stomatal pores get closed when carbon dioxide is no longer needed for the process of photosynthesis. The guard cells swell when movement of water takes place inside these pores, and thus, the opening of stomatal pores occurs, and as water moves out, the guard cell closes. Thus, guard cells play an essential role in regulating water loss.