9th Class Biology – Short Questions & Answers
-
What is the role of chloroplasts in plants?
Chloroplasts are organelles in plant cells that contain chlorophyll, the pigment responsible for capturing light energy for photosynthesis.
-
What is the process of root pressure?
Root pressure is the force that pushes water and nutrients up from the roots to the stems and leaves, helping to overcome gravity.
-
What is the importance of nitrogen fixation in plants?
Nitrogen fixation is the process by which certain bacteria convert nitrogen gas from the atmosphere into ammonia, which plants can use to synthesize proteins and other essential molecules.
-
What is the difference between aerobic and anaerobic respiration?
Aerobic respiration occurs in the presence of oxygen and produces more ATP. Anaerobic respiration occurs without oxygen and produces less ATP, often resulting in the production of lactic acid or ethanol.
-
What is the lock and key model of enzyme action?
The lock and key model suggests that the enzyme’s active site is specifically shaped to fit the substrate, like a key fitting into a lock.
-
What are the main stages of photosynthesis?
Photosynthesis occurs in two stages: Light-dependent reactions: These occur in the thylakoid membranes of chloroplasts and require sunlight to produce ATP and NADPH. Light-independent reactions (Calvin cycle): These occur in the stroma of the chloroplast and use ATP and NADPH to synthesize glucose from carbon dioxide.
-
What factors affect enzyme activity?
Factors that affect enzyme activity include temperature, pH, enzyme concentration, and substrate concentration.
-
How is energy transferred in the cell?
Energy is transferred in cells primarily through ATP. When ATP is hydrolyzed (broken down), it releases energy that is used for various cellular processes. The conversion of ADP (adenosine diphosphate) back to ATP is essential for energy storage.
-
What is an active site?
The active site is the region on an enzyme where the substrate binds and where the chemical reaction takes place.
-
What is the role of chlorophyll in photosynthesis?
Chlorophyll is a pigment found in chloroplasts that absorbs light energy, particularly from the blue and red wavelengths. This energy is used to drive the reactions of photosynthesis.
Follow Us
Recent Blog Posts
Blog Categories
- No categories