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Tissues
Is the outer most protective layer is continuous? If not, what interruptions are usually found on leaves and herbaceous parts of the plant?
The outermost layer of cells i.e., usually the epidermis is not continuous at some places e.g., on the surface of leaves or green herbaceous stems.
The epidermis of the young shoot and leaves contains numerous minute pores called stomata. Each stomatal opening is surrounded by two semilunar cells known as the guard cells.
The term ‘stoma’ (plural-stomata) is applied to the stomatal opening plus the guard cells. The guard cells are living and contain chloroplasts. Their inner walls (wall towards opening) are thicker and outer walls thinner. The guard cells regulate the opening and closing of the stomatal pore.
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How is a prokaryotic cell different from a eukaryotic cell?
What would happen if the plasma membrane ruptures or breaks down?
What would happen to the life of a cell if there was no Golgi apparatus?
Which organelle is known as the powerhouse of the cell? Why?
Where do the lipids and proteins constituting the cell membrane get synthesized?
How does an Amoeba obtain its food?
What is osmosis?
Carry out the following osmosis experiment:
Take four peeled potato halves and hollow each one out to make potato cups. One of these potato cups should be made from a boiled potato. Put each potato cup in a trough containing water. Now,
(a) keep cup A empty
(b) put one teaspoon sugar in cup B
(c) put one teaspoon salt in cup C
(d) put one teaspoon sugar in boiled potato cup D.
Keep this setup for two hours. Then observe the four potato cups and answer the following :
(i) Explain why water gathers in the hollowed portion of B and C?
(ii) Why is potato A necessary for this experiment?
(iii) Explain why water does not gather in the hollowed out portions of A and D.
By which instrument you can see internal structure of onion peel cell?
Do different organisms have different types of basic building units ? Briefly explain.
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