Question
Write Short note: Multiple fission.
✓
Answer
During unfavourable conditions when there is lack of food. multiple fission is shown by amoeba. Amoeba forms protective covering and becomes encysted. Inside the cyst, amoeba undergoes repeated nuclear division. This is followed by cytoplasmic divisions. Many amoebulae are formed which remain dormant inside the cyst. When favourable conditions reappear, they come out by breaking the cyst.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
Three lenses having powers 2, 2.5 and 1.7 D are kept touching in a row. What is the total power of the lens combination?
Write short note: Coelom.
Every household produces a lot of material A daily. In one of the methods of disposal B, material A is burned at a very high temperature of about 1000°C in a structure called C. During this process, the organic matter present is removed as D and E whereas F is left behind (which can be dumped in a landfill site).
- What is material A?
- Name the method of disposal B.
- What is structure C known as?
- What are (i) D (ii) E, and (iii) F?
- This method is especially suitable for the disposal of materials produced by certain institutions. Name such institutions.
Observe the figure and answer the following.
- Write the name of the method.
- What is used as anode and cathode in this method?
- Write the molecular formula and use of cryolite.
- Write anode reaction.
- Write cathode reaction.
(marginal, array, cell, panel, string, current, power station, potential difference).
Many solar panels are connected in series and in parallel to generate required ………… and ……… Solar …………. is the basic unit in solar electric plant. Many solar cells come together to form a solar …………… Many solar panels connected in series form a solar ………., and many solar strings connected in parallel form a solar …………. As we can obtain as much electrical power as needed, they are used in applications which need ……….. power (e.g. calculators that run on solar energy) to ……….. of MW capacity.
Many solar panels are connected in series and in parallel to generate required ………… and ……… Solar …………. is the basic unit in solar electric plant. Many solar cells come together to form a solar …………… Many solar panels connected in series form a solar ………., and many solar strings connected in parallel form a solar …………. As we can obtain as much electrical power as needed, they are used in applications which need ……….. power (e.g. calculators that run on solar energy) to ……….. of MW capacity.
How do the following change on going from left to right in a period of the periodic table?
- Chemical reactivity of elements.
- Nature of oxides of elements Give examples in support of your answer.
Which is the energy currency of the cell? Explain.
write the answers to the questions with reference to the structure of the periodic table.
(a) Which points are considered for the modern periodic table?
(b) How are blocks indicated?
(c) Which elements are present near the zig-zag line?
(d) Draw the electronic configuration of the second-row elements of first group in the periodic table.
(e) In a periodic table while going from left to right atomic radius decreases. Explain. (Practice Activity Sheet – 1)
Construction of a compound microscope:
(1) A compound microscope consists of a metal tube fitted with two convex lenses at the two ends. These lenses are called the objective lens (the lens directed towards the object) and the eyepiece (the lens directed towards the eye). Both the lenses are small in size, but the cross section of the objective lens is less than that of the eyepiece. The objective lens has a short focal length. The focal length of the eyepiece is more than that of the objective lens.(2) The metal tube is mounted on a stand. The principal axes of the objective lens and the eyepiece are along the same line. The distance between the object and the objective lens can be changed with a screw. It is possible to change the distance between the objective lens and the eyepiece.
Working:
(1) The object to be observed is illuminated and placed in front of the objective lens, slightly beyond the focal length of the objective lens. Its real, inverted and enlarged image is formed by the, objective lens on the other side.
(2) This intermediate image lies within the focal length of the eyepiece. It serves as an object for the eyepiece. The eyepiece works as a simple microscope. The final image is virtual, highly enlarged and inverted with respect to the original object. It can be formed at the minimum distance of distinct vision from the eyepiece. The final image is observed by keeping the eye close to the eyepiece.
Use: This microscope is used to observe blood cells, microorganisms, etc.
1.In a compound microscope, which lens has greater focal length?
2.Where do you place the object to be observed with a compound microscope?
3.State which distance is adjusted to observe the object with a compound microscope.
4.State the nature of the final image in compound microscope relative to the object.
5.State the use of a compound microscope.
(1) A compound microscope consists of a metal tube fitted with two convex lenses at the two ends. These lenses are called the objective lens (the lens directed towards the object) and the eyepiece (the lens directed towards the eye). Both the lenses are small in size, but the cross section of the objective lens is less than that of the eyepiece. The objective lens has a short focal length. The focal length of the eyepiece is more than that of the objective lens.(2) The metal tube is mounted on a stand. The principal axes of the objective lens and the eyepiece are along the same line. The distance between the object and the objective lens can be changed with a screw. It is possible to change the distance between the objective lens and the eyepiece.
Working:
(1) The object to be observed is illuminated and placed in front of the objective lens, slightly beyond the focal length of the objective lens. Its real, inverted and enlarged image is formed by the, objective lens on the other side.
(2) This intermediate image lies within the focal length of the eyepiece. It serves as an object for the eyepiece. The eyepiece works as a simple microscope. The final image is virtual, highly enlarged and inverted with respect to the original object. It can be formed at the minimum distance of distinct vision from the eyepiece. The final image is observed by keeping the eye close to the eyepiece.
Use: This microscope is used to observe blood cells, microorganisms, etc.
1.In a compound microscope, which lens has greater focal length?
2.Where do you place the object to be observed with a compound microscope?
3.State which distance is adjusted to observe the object with a compound microscope.
4.State the nature of the final image in compound microscope relative to the object.
5.State the use of a compound microscope.
Observe the figure and answer the questions given below.
(a) What do these figures indicate?
(b) Which gadgets can be misused for these?
(c) Give two examples of such events.
(d) Name the act amended by Government of Maharashtra to control such events.
(e) What care should be taken by a person to avoid such events?