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?
A motorboat starting from rest on a lake accelerates in a straight line at a constant rate of 3.0 m s-2 for 8.0 s. How far does the boat travel during this time?
In which of the three media, air, water or iron, does sound travel the fastest at a particular temperature?
Soni says that the acceleration in an object could be zero even when several forces are acting on it. Do you agree with her? Why?
Explain the working and application of a sonar.
How does the sound produced by a vibrating object in a medium reach your ear?
Define the atomic mass unit.
Draw a sketch of Bohr’s model of an atom with three shells.
A freely falling object eventually stops on reaching the ground. What happenes to its kinetic energy?
The average atomic mass of a sample of an element X is 16.2 u. What are the percentages of isotopes 168 X and 188 X in the sample?
Two objects, each of mass 1.5 kg, are moving in the same straight line but in opposite directions. The velocity of each object is 2.5 m s-1 before the collision during which they stick together. What will be the velocity of the combined object after collision?