How does the cork act as a protective tissue?
Cork goes about as a defensive tissue since its cells are dead and minimalistically orchestrated without intercellular spaces. They have testimony of suberin on the dividers that make them impenetrable to gases and water.
Diagrammatically show the difference between the three types of muscle fibres.
What does a neuron look like?
Draw a labelled diagram of a neuron.
Complete the table:
Give three features of cardiac muscles.
Where is apical meristem found?
What are the functions of the stomata?
How many types of elements together make up the xylem tissue? Name them.
What is a tissue?
Name the following.
(a) Tissue that forms the inner lining of our mouth.
(b) Tissue that connects muscle to bone in humans.
(c) Tissue that transports food in plants.
(d) Tissue that stores fat in our body.
(e) Connective tissue with a fluid matrix.
(f) Tissue present in the brain.
Which of the following has more inertia: (a) a rubber ball and a stone of the same size? (b) a bicycle and a train? (c) a five-rupees coin and a one-rupee coin?
State the universal law of gravitation.
Which of the following are matter?
Chair, air, love, smell, hate, almonds, thought, cold, cold-drink, smell of perfume.
A force of 7 N acts on an object. The displacement is, say 8 m, in the direction of the force (Fig. 11.3). Let us take it that the force acts on the object through the displacement. What is the work done in this case?
What is meant by a pure substance?
How does the sound produced by a vibrating object in a medium reach your ear?
In a reaction, 5.3 g of sodium carbonate reacted with 6 g of ethanoic acid. The products were 2.2 g of carbon dioxide, 0.9 g water and 8.2 g of sodium observations are in agreement with the law of conservation of mass.
sodium carbonate + ethanoic acid → sodium ethanoate + carbon dioxide + water
What are canal rays?
State any two conditions essential for good health.
How is our atmosphere different from the atmospheres on Venus and Mars?
Guess which sound has a higher pitch; guitar or car horn?
Carry out the following osmosis experiment:
Take four peeled potato halves and scoos 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 the boiled potato cup D.
Keep these 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.
If number of electrons in an atom is 8 and number of protons is also 8, then (i) what is the atomic number of the atom? and (ii) what is the charge on the atom?
For the following statements, write T for True and F for False.
(a) J.J. Thomson proposed that the nucleus of an atom contains only nucleons.
(b) A neutron is formed by an electron and a proton combining together. Therefore, it is neutral.
(c) The mass of an electron is about 1/2000 times that of proton.
(d) An isotope of iodine is used for making tincture iodine, which is used as a medicine.
Put tick (✓) against correct choice and cross (✕) against wrong choice in questions 15, 16 and 17.
For the symbol H,D and T tabulate three sub-atomic particles found in each of them.
Where are proteins synthesised inside the cell?
Write the electronic configuration of any one pair of isotopes and isobars.
In which of the three media, air, water or iron, does sound travel the fastest at a particular temperature?
How do storage grain losses occur?
Which wave property determines
(a) loudness, (b) pitch?