Morphology of Flowering Plants — BIOLOGY STD 11 Science — Question

How are tracheids different from vessels found in angiosperms? Give a labelled sketch of each of them.

Give reason for each of the following:

1. The vascular bundles of an isobilateral leaf are near similar in size, except that in the midrib.
2. Heart wood is dark brown in colour.
3. Cells of phellem/cork are impervious to water.
4. Quantity of secondary xylem produced is more than the quantity of secondary phloem during secondary growth.
5. Phellogen is a secondary meristem.

Explain with examples the categories determined on the basis of nitrogenous excreting substances.

How are amides formed? Name two important amides found in plants.

It is observed that deficiency of a particular element showed its symptoms initially in older leaves and then in younger leaves.

1. Does it indicate that the element is actively mobilised or relatively immobile?
2. Name two elements which are highly mobile and two which are relatively immobile.

How is the aspect of mobility of elements important to horticulture and agriculture?

Explain how ATP synthase (complex V) helps in the synthesis of ATP in mitochondria with the help of a diagram.

Photosynthesis not only facilitates production of food but also cleans up the environment. Which of the following is similar to this multipronged effect of photosynthesis? Explain how deforestation affects our environment.

1. An automobile not only carries people but also releases carbon dioxide in the air.
2. A cow not only gives milk but also produces methane which is a greenhouse gas.
3. A cow not only gives milk but also produces cowdung which can be used as kitchen fuel.

Briefly describe the life cycle phases of fungi.

What is meant by development in plants? Represent schematically the processes in the development of a plant cell.

Proteins have been called 'biological polymers'.Explain.