Differentiate between striated, unstriated and cardiac muscles on the basis of their structure and site/location in the body.
Striated muscles | Unstriated muscles | Cardiac muscles |
---|---|---|
1. The cells of striated muscles are long, cylindrical, unbranched and multinucleate. | 1. The cells of unstriated muscles are long and pointed at the ends, spindle shaped and uninucleate. | 1. The cells of cardiac muscles are cylindrical, branched and uninucleate. |
2. Many nuclei which are situated towards the periphery of muscle fibre. | 2. The cells have only one nucleus situated in the center. | 2. Each cell contains one or two nuclei situated in the center. |
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?
What are the constituents of phloem?
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?
What factors may be responsible for losses of grains during storage?
Name the technique to separate
(i) butter from curd,
(ii) salt from sea-water,
(iii) camphor from salt.
Joseph jogs from one end A to the other end B of a straight 300 m road in 2 minutes 50 seconds and then turns around and jogs 100 m back to point C in another 1 minute. What are Joseph’s average speeds and velocities in jogging (a) from A to B and (b) from A to C?
Which of the following materials fall in the category of a “pure substance”?
(a) Ice
(b) Milk
(c) Iron
(d) Hydrochloric acid
(e) Calcium oxide
(f) Mercury
(g) Brick
(h) Wood
(i) Air.
Compare the use of manure and fertilizers in maintaining soil fertility.
Give reason for the following observations.
(a) Naphthalene balls disappear with time without leaving any solid.
(b) We can get the smell of perfume sitting several metres away.
Calculate the wavelength of a sound wave whose frequency is 220 Hz and speed is 440 m/s in a given medium.
A bus starting from rest moves with a uniform acceleration of 0.1 m s-2 for 2 minutes. Find (a) the speed acquired, (b) the distance travelled.
Does the transfer of energy take place when you push a huge rock with all your might and fail to move it? Where is the energy you spend going?
What is genetic manipulation? How is it useful in agricultural practices?