CBSE Class 11 Biology NCERT Solutions: Chapter 13, Photosynthesis in Higher Plants
In this era of technology, students may find the free study material on various online portals but the real concern is the quality and accuracy of the stuff that you will refer for the good results in your exams. Students should pick the content from reliable sources only.
Jagranjosh.com is always committed to bring the study material which would make learning easy and simple. Our experts work to deliver the precise and exclusive content to our users.
In this article we are providing the NCERT solutions for class 11 Biology by the subject matter experts. Answers given here are designed to contain the appropriate concepts. All the solutions have been collated in the form of PDF which students can download for free of cost and refer the same whenever required.
Some of the questions and their solutions from NCERT Solutions for Class 11: Photosynthesis in Higher Plants, are as follows:
Q. By looking at a plant externally can you tell whether a plant is C3 or C4? Why and how?
Ans. No, it is not possible to identify a plant as C3 or C4, merely by observing its leaves and other morphological features externally. However, the histological study of bundle sheath cells in the leaves can easily give clues about the plant type. Also, unlike C3 plants, the leaves of C4 plants have a special anatomy called Kranz anatomy, which differentiates the C4 plants from C3 plants. For example, although wheat and maize are grasses, wheat is a C3 plant, while maize is a C4 plant.
Q. By looking at which internal structure of a plant, can you tell whether a plant is C3 or C4? Explain.
Ans. Unlike C3 plants, the leaves of C4 plants have a special anatomy called Kranz anatomy, which differentiates the C4 plants from C3 plants. In C4 plants, the vein of the leaf is surrounded by bundle-sheath cells. These cells have a large number of chloroplasts. They are thick-walled and are impervious to gaseous exchange. They have no intercellular spaces.All these anatomical features can help us to differentiate C3 and C4 plants.
Q. Even though a very few cells in a C4 plant carry out the biosynthetic – Calvin pathway, yet they are highly productive. Can you discuss why?
Ans. The productivity of a plant is measured by the rate at which it photosynthesises. C4 plants chemically fix carbon dioxide in the cells of mesophyll. The increase in CO2 ensures that the enzyme RuBisCo does not act as an oxygenase, but as a carboxylase. This reduces the photorespiration which in turn increases the rate of photosynthesis in C4 plants. Thus, C4 plants are highly productive.
Q. RuBisCo is an enzyme that acts both as a carboxylase and oxygenase. Why do you think RuBisCo carries out more carboxylation in C4 plants?
Ans. The enzyme RuBisCo (Ribulose biphophate caiboxylase and oxygenase) has affinity for both carbon dioxide and oxygen. However, it is the relative concentiation of CO2 and O2 that determines which of the two will bind to the enzyme. But actually RuBisCo has much greater affinity for CO2 than O2. This is because in case of C4 plants there is a high concentration of CO2 at the enzyme site, which prevents the photorespiration to occur. Hence RuBisCo carries out more carboxylation in C4 plants.
Get the complete the NCERT solutions for Class 11: Photosynthesis in Higher Plants, from the following link:
Class 11 Biology NCERT Chapter: Photosynthesis in Higher Plants
At the time of solving the NCERT questions, if you find yourself puzzled or unaware of any particular concept, then you should go through the NCERT chapter once again. Taking a thorough reading of the theories given in NCERT book will help you understand the problem discussed in a question and then come with an appropriate answer.
Main topics discussed in Class 11 Biology chapter: Photosynthesis in Higher Plants are:
- Early experiments on photosynthesis.
- Where does photosynthesis take place?
- Pigments are involved in photosynthesis
- Light reaction
- Electron transport
- Where are the atp and nadph used?
- C4 pathway
- Factors affecting photosynthesis.
Find below the link to download the complete Chapter:
To get more related articles for CBSE Class 11, click here