(i) The word Arthropod means 'jointed legs'.
(ii) The body is divided into head, thorax and abdomen.
(iii) The coelomic cavity is filled with haemolymph (blood).
(iv) Open circulatory system is seen.
(v) Exoskeleton has to be shedded periodically in a process called moulting.
(vi) Small arthropods directly absorb oxygen through their body surface.

Absence of Cranium.

Embryonated eggs.

Atomic number = No. of protons = No. of electrons
Atomic number = 8
Mass number = No. of protons + neutrons
Mass number = 8 + 8 = 16

A reaction where two or more substances combine to form a single substance.

ENIAC- A computer had approximately 18,000 vacuum tubes. The size occupied by the ENIAC could be equivalent to a class room. ENIAC, which was used by the American Military in 1946 to predict the traj ectory of artillery shells, recognized as the world's first general purpose computer.

Beaker with hot water turns red faster. The rate of change increases with increase in temperature.

Canning, Smoking & Freezing.

Brick powder.

Focal length of a spherical mirror depends on radius of curvature.

residue - filtrate.

Speed is the rate of change of distance or the distance travelled in unit time.
Speed = \(\frac { Distance\ travelled }{ time\ taken } \).

(i) The body is said to be in the state of rest when it remains in the same position with respect to time.
(ii) The body is said to be in the state of motion, when it continuously changes its position with respect to time.

(i) tera
(ii) 10³
(iii) P
(iv) giga
(v) G

Frogs are live in aquatic and land. So this double life is expressed as amphibians. So frogs are called as amphibians.

In the jelly fish its tentacles bear stinging cells called nematocysts.

At infinity.

  (i) Convex and (ii) Concave

Deficiency of disorder disease is the factor required for the absorption of vitamin D.

(a) Tropic movement
(b) Nastic movement

1. Laws of conservation of mass:
In a chemical change the total mass of the reactant is equal to the total mass of the products.
2. Law of definite proportion:
"A pure chemical compound prepared by any method consists of the same elements combined together in the fixed proportion by mass".
3. Law of multiple proportion: 
When two elements A and B combine together to form more than one compound, then masses of A which separately combines with a fixed mass of B are in simple ratio.
4. Laws of Reciprocal proportion:
"If two elements combine separately the same weight of a third element, the ratios of the masses in which they do so are either the same or a simple multiple of the mass ratio in which they combine.
5. Gay Lussac's law of combining volumes:
Whenever gases react together, the volumes of the reacting gases as well as the products bear a simple whole number ratio, provided all the volumes are measured under similar conditions of temperature and pressure.

Non-directional response of a plants part to stimulus is known as nastic movement.

Separation of salt from sea water to get potable water is called desalination.

Celsius = (F – 32) × \(\frac{5}{9}\)= (104 - 32) ×\(\frac{5}{9}\) = 72 × \(\frac{5}{9}\) = 40°C.