GATE Questions

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A door is not a door when it is a jar.

A substance that cannot be decomposed (broken down) into simpler substances by ordinary chemical means.

Examples: gold, iron, carbon, hydrogen, oxygen, nitrogen.

Material composed of only one kind of matter throughout (same atoms or same molecules).

Any number which can be expressed as a fraction of two integers like P & Q as P/Q where Q is not equal to zero.

Every integer is a rational number since Q can be 1.

Hence, in the given options, 4 can be expressed as a simple fraction as 4/1. And all other options cannot be expressed as fractions.

Hence, 4 is a rational number in the given options.

Protons carry a positive electrical charge, electrons carry a negative electrical charge and neutrons carry no electrical charge at all. The protons and neutrons cluster together in the central part of the atom, called the nucleus, and the electrons 'orbit' the nucleus.

Amino acids are organic compounds containing amine (-NH2) and carboxyl (-COOH) functional groups, along with a side chain (R group) specific to each amino acid.

Depending on the nature of the side chain groups, three classes of aminoacids can e distinguished:

1. Amino acids with H ond donor and acceptor groups.

Histidine, lysine, aspartic acid, threonine,...

2. Amino acids with donor grups only.

Arginine, tryptophan and cysteine.

3. Amino acids with acceptor groups only.

Asparagine and glutamine.

Plants make their own food through the process of photosynthesis. Plants are self-sufficient. Green plants have the ability to prepare their own food and this is the reason why they are called autotrophs.

They make their own food through the process of photosynthesis using light energy to make sugars from carbon dioxide (C02) and water (H20). The chlorophyll which is present in the leaves is the main reason for the production of food in the plants and it is the reason for the greenery of the leaves too.

Electric current produces a magnetic field. This magnetic field can be visualized as a pattern of circular field lines surrounding a wire.