Q. Mention any four flight adaptations in birds.

Q. What is geothermal energy?

Q. Boy A argues that light wave is a transverse wave. Boy B argues that it is an electromagnetic wave. Whose argument is correct? Justify your answer scientifically.

Q. A man is standing between hill A and hill B, claps louder. He hears an echo after $4$ seconds from hill A and after $6$ seconds from hill B. The speed of sound in air is $340m{s}^{-1}$. Calculate the distance between the two hills.

Q. What are polyploids? Write their limitations.

Q. What is superconductivity? Mention any two uses of superconductors.

Q. Write any two differences between diesel engine and petrol engine.

Q. if the percentage of air pollution from different sources are given in the table. With the help of this, answer the following questions :

Sources of air pollution	Industry	Transportation	Consumer & commercial products	Commercial & Residential heating	Agriculture	Other
Percentage	52%	27%	8%	1%	10%	2%

a) Which are the two sources to be monitored more to control air pollution?
(b) Mention the preventive measure for each one of these two sources to control air pollution?

Q. Draw the diagram showing the expansion stroke of steam engine.

Q. Write the differences between tendons and ligaments.

Q. Write any four physical features of Australopithecus man.

Q. A student finds a flower in his school campus and decides that it is the flower of a monocot plant. The reason for his conclusion is

Q. A paleontologist observes the jaw of an animal and concludes that it belongs to mammals. Give a reason for his conclusion.

Q. Give any four reasons to decide that internal combustion engines are advantageous over steam engines.

Q. The energy conversion based on the principle of photovoltaic effect is?

Q. Mention the function of sympathetic and parasympathetic nervous system with respect to the pupil of eye.

Q. Draw the diagram of a nuclear power reactor and label the following parts.
(a) Reflector
(b) Heat exchanger.

Q. Explain the double helix structure of DNA molecule.

Q. These diseases can be controlled by eradicating mosquitoes

Q. What are the physical changes that resulted in the upright posture in the course of evolution of human?

Q. What is a transistor? Mention any two uses of transistor.

Q. Use of detergents is hazardous to the aquatic life because, they

Q. The figure of longitudinal section of a plant tissuse is given below. Name the part labelled as 'A' and mention its function. Name the other components of this tissue.

Q. A diode is connected in a circuit as shown in the figure. The correct statement related to this figure is?

Q. Draw the vertical section of the human eye and label the following parts.
(a) Lens (b) Fovea

Q. A special property of DNA that ensures the equal distribution of similar genetic material to the offsprings is

Q. Explain the Carl Correns's monohybrid cross in Four O'clock plant with the help of schematic representation. Mention the phenotype ratio and genotype ratio of plants occurred in $F_2$ generation.

Q. Name the two major groups of fishes based on the composition of endoskeleton.

Q. Mention the advantages of using antioxidants and colourants in food processing.

Q. The technique used to track air craft is?