Reproduction through spores gives several advantages to an organism. ... Spores can remain dormant till favourable conditions become available. Spores help an organism to tide over the bad phase. Spores can be spread through water, air, or animals and thus is good for the spread of an organism to more places.

Reproduction through spores gives several advantages to an organism. Some of them are as follows:
a. Spores can remain dormant till favourable conditions become available.
b. Spores help an organism to tide over the bad phase.
c. Spores can be spread through water, air or animals and thus is good for the spread of an organism to more places.

Variation beneficial to the species
Even so, for factors beyond the control of the species, such locations will alter, and can even destroy the entire species. If any differences in all of these species were to be found in a few individuals, they would have a chance of surviving.

Variations can be beneficial or harmful according to the ecological niche of the organism.
A variation suitable for the particular niche is selected by nature in evolution. Thus variations are necessary for the survival of the species.
Variation is important for the evolution of the species.
Example
A population of heat resistant bacteria in the temperature of the water survives if the temperature of water increases by global warming but most other bacteria would die.

DNA determines the body design of an individual. The DNA that gets transferred from parents to offsprings makes them look similar. DNA copying is important for reproduction. Additional copies of DNA are made during replication which is necessary for the new cells formed after cell division. Moreover, some minor alterations during DNA replication are responsible for bringing variations in the long run.

Carbon form large number of compounds due to the following properties:

         (a) Catenation → Carbon shows the property of catenation that is the ability to form bonds with other carbon atoms forming long chains both branched and unbranched chains, and even rings.

         (b) Tetravalency → Carbon has valency 4, it is capable of bonding with 4 other carbon atoms or atoms of other non-covalent elements, giving rise to compounds with specific properties depending on the elements present in the compound.

         (c) Isomerism → Carbon compounds show the property of isomerism that is compounds having same molecular formula but different structural formula.

In very simple words, maturing is aging. It is the process with which we develop, grow and change throughout our entire lives. In children, maturation means going through their development stages. It is them being able to do tasks and things they could n

Soda-acid fire extinguishers comprises of sodium bicarbonate and sulphuric acid. It is the most efficient house-hold fire extinguisher. It consists of a strong iron vessel with a side discharge nozzle. The iron vessel is filled with a sodium bicarbonate solution.

The ore is heated in a regular supply of air in a furnace at a temperature below the melting point of a metal.

Example=conversion ofzinc sulphide into zinc oxide.

2ZnS+3O₂--->2ZnO + 2SO₂

The availability of ions is very important to conduct electricity. Distilled water is a pure type of water which does not contain any ions in it. Whereas rainwater contains dissolved gasses such as SO₂, CO₂.

These gases dissolve in water to form some kind of acids like carbonic acids which dissociates to give ions. Thus rainwater is conducting electricity while distilled water is not conducting electricity.

Mendel performed an experiments in which he took a tall plant with round seeds and a short plant with wrinkled-seeds. In F1, They were all tall and had round seeds. Tallness and round seeds were thus dominant traits. When, he used these F1 progeny to generate F2 progeny by self-pollination, he found that some F2 progeny were tall plants with round seeds, and some were short plants with wrinkled seeds. At the same time there tall plants, but had wrinkled seeds, while others were short, but had round seeds. Thus, Mendel’s experiments show that the tall/short trait and the round seed/wrinkled seed trait are independently inherited.

Alveoli are the balloon like structures present in lungs.

Mendel conducted breeding experiments with garden peas:

• He studied plants (pure) of a tall/short varieties.
• He crossed them and obtained F t progeny.
• He found that Fj progeny was all tall plants.
• He selfed the (hybrid) plants of Fj progeny.
• He found that in F2 progeny there were tall as well as short plants.
• The three quarter plants were tall and one quarter was short .

The path along which north pole moves in a magnetic field is called magnetic lines of force or magnetic field line. The direction of magnetic field is taken to be the direction in which a north pole of compass needle move inside it. Inside the magnet direction of field line is from south pole to north pole.

1 coulomb is that quantity of electric charge which exerts a force of 9 x 10⁹ N on an equal charge placed at a distance of 1 m from it.

The atomic number of carbon is 6 and the atomic mass is 12.01gmol-1.

R=20 Ω  

Let,Length of wire is L and when it drawn out, its new length is 2L

The volume of wire in both the situations remains constant.So, it the length of wire doubled, the area of cross section of wire becomes half.

So, the new resistance of wire-
R_new = 2l/(A/2)

=4LA

=4×Old resistance of wire           (Because, R=L/A)

=4×20 = 80 Ω

Somatic cells are non reproductive cells.These help in carry out other body functions other than reproduction

Electrical engineering is an engineering discipline concerned with the study, design and application of equipment, devices and systems which use electricity, electronics, and electromagnetism. It emerged as an identifiable occupation in the latter half of the 19th century after commercialization of the electric telegraph, the telephone, and electrical power generation, distribution and use.

Electrical engineering is now divided into a wide range of fields, including computer engineering, systems engineering, power engineering, telecommunications, radio-frequency engineering, signal processing, instrumentation, and electronics. Many of these disciplines overlap with other engineering branches, spanning a huge number of specializations including hardware engineering, power electronics, electromagnetics and waves, microwave engineering, nanotechnology, electrochemistry, renewable energies, mechatronics, and electrical materials science

1. In the litmus test experiment the red litmus solution turns into blue when sodium hydroxide is added. Therefore bases such as NaOH show basic character.
2. Sodium hydroxide reacts with active metals such as zinc to form sodium zincate and liberate hydrogen gas.
3. NaOH does not react with sodium carbonate.

The series which consists of similar structures and similar chemical properties in which the successive compounds differs by a CH₂ group is termed as homologous series. The two characteristics of homologous series are as follows: 

1. The members of the homologous series consists of same general formula such as Alkanes have general formula C_nH_2n+2 

2. The two adjacent homologues have a difference of molecular mass of 14 u 

(i) All the members of a homologous series can be represented by the same-general formula. 

(ii) The difference in the molecular mass of any two adjacent homologues is 14 u. 

The general formula for the alkenes is: C_nH_2n 

The first member of the series of alkenes is: Ethane which has formula CH₄