Neural Control and Coordination — BIOLOGY STD 11 Science — Question

Each plant or group of plants has some phylogenetic significance in relation to evolution: Cycas, one of the few living members of gymnosperms is called as the ‘relic of past’. Can you establish a phylogenetic relationship of Cycas with any other group of plants that justifies the above statement?

Plants require water for their survival. But when watered excessively, plants die. Discuss.

Give the scientific terms for the following:

1. Loss of water from leaves through stomata in the form of water vapour.
2. Movement of water in roots exclusively through the cell wall.
3. Water adsorbed by solids, causing them to enormously increase in volume.

Write the scientific names of following organisms?

1. Cat.
2. Rose.
3. Sparrow.

Give the cause for the Heart sounds.

When a freshly collected Spirogyra filament is kept in a 10% potassium nitrate solution, it is observed that the protoplasm shrinks in size:

1. What is this phenomenon called?
2. What will happen if the filament is replaced in distilled water?

Describe reflex action.

Explain the main characteristics of pteridophytes.

Arya went to a bird sanctuary with her family. She saw numerous birds there and was amazed by the colourful and vibrant world of flying birds. She also saw ostriches there but they were not flying seeing this, she asked her mother who is an ornithologist) why only birds can fly, while all other animals cannot. She also asked her mother about the birds that cannot fly.Her mother explained Arya about birds and their characteristic features. Arya felt happy knowing knowledge:

1. Which characteristic features of Aves.
2. What are the flight adaptations of birds?
3. Name few flightless birds.
4. What values are shown by Arya?

What is the function of lenticels in woody trees?