Indicate whether the following statements are True (T) or False (F):
(a) Oviparous animals give birth to young ones. ( )
(b) Each sperm is a single cell. ( )
(c) External fertilization takes place in frog. ( )
(d) A new human individual develops from a cell called gamete. ( )
(e) Egg laid after fertilization is made up of a single cell. ( )
(f) Amoeba reproduces by budding. ( )
(g) Fertilization is necessary even in asexual reproduction. ( )
(h) Binary fission is a method of asexual reproduction. ( )
(i) A zygote is formed as a result of fertilization. ( )
(j) An embryo is made up of a single cell. ( )
(a) False
This statement is false because oviparous animals lay eggs and viviparous animals give birth to young ones.
(b) True
This statement is true because each sperm is a single cell and an egg is also a single cell.
(c) True
External fertilization takes place outside the female body; they lay eggs and then eggs got hatch and young ones are produced. So, this statement is true that external fertilization takes place in frogs.
(d) False
This statement is false because a new human individual develops not from a cell called gamete. A new individual is formed due to the fusion of two single cells i.e. sperm and egg.
(e) True
Yes, this statement is true because egg is a single cell.
(f) False
This statement is false because amoeba reproduce by binary fission. It is a type of asexual reproduction.
(g) False
This statement is false because fertilization only occurs in sexual reproduction, not in asexual reproduction.
(h) True
This statement is true because asexual reproduction is that in which only single parent is involved. Binary fission, budding are the types of asexual reproduction.
(i) True
Fusion of male and female gamete occurs and forms an zygote. This process of fusion is known as fertilization.
(j) False
This statement is false because embryo is formed by the repeated divisions of zygote or we can say that embryo is the mature zygote.
Describe with the help of a diagram an instrument which can be used to detect a charged body.
Sketch larynx and explain its function in your own words.
Arrange the following boxes in proper order to make a flow chart of sugarcane crop production.
Make a labelled diagram of a candle flame.
What is metamorphosis? Give examples.
The following Table shows the total power shortage in India from 1991– 1997. Show the data in the form of a graph. Plot shortage percentage for the years on the Y-axis and the year on the X-axis.
Make sketches of animal and plant cells. State three differences between them.
What is a constellation? Name any two constellations.
Describe the construction of a kaleidoscope.
Complete the crossword with the help of clues given below:
Across
1. This is necessary for photosynthesis.
3. Term for component present in the cytoplasm.
6. The living substance in the cell.
8. Units of inheritance present on the chromosomes.
Down
1. Green plastids.
2. Formed by collection of tissues.
4. It separates the contents of the cell from the surrounding medium.
5. Empty structure in the cytoplasm.
7. A group of cells.
Describe an activity to show that the incident ray, the reflected ray and the normal at the point of incidence lie in the same plane.
What is metamorphosis? Give examples.
Fill in the blanks in the following :
(a) A person 1 m in front of a plane mirror seems to be _______________ m from his image.
(b) If you touch your ____________ ear with right hand in front of a plane mirror it will be seen in the mirror that your right ear is touched with ____________
(c) The size of the pupil becomes ____________ when you see in dim light.
(d) Night birds have ____________ cones than rods in their eyes..
An archer stretches her bow while taking aim at the target. She then releases the arrow, which begins to move towards the target. Based on this information fill up the gaps in the following statements using the following terms:
muscular, contact, non-contact, gravity, friction, shape, attraction
(a) To stretch the bow, the archer applies a force that causes a change in its ——.
(b) The force applied by the archer to stretch the bow is an example of ——— force.
(c) The type of force responsible for a change in the state of motion of the arrow is an example of a ———— force.
(d) While the arrow moves towards its target, the forces acting on it are due to ———— and that due to ———— of air.
State the laws of reflection.
Name the microorganisms which can fix atmospheric nitrogen in the soil.
Prepare a list of objects around you that are electroplated.
The radius of Jupiter is 11 times the radius of the Earth. Calculate the ratio of the volumes of Jupiter and the Earth. How many Earths can Jupiter accomodate?
Complete the following word puzzle with the help of clues given below.
Down
1. Providing water to the crops.
2. Keeping crop grains for a long time under proper conditions.
5. Certain plants of the same kind grown on a large scale.
Across
3. A machine used for cutting the matured crop.
4. A rabi crop that is also one of the pulses.
6. A process of separating the grain from chaff.
Give two difference between a zygote and a foetus.