These are Properties of anode rays as under:

(i) They consist of Positively charged particles. Their mass is virtually the same as that of the atoms from which they are derived and is found to be equal to the atomic mass of the gas in the discharge tube.
(ii)They travel in straight lines.
(iii)They are capable of producing physical and chemical changes.
(iv) They can penetrate thin metal foils.
(v)They can produce ionization in gases.
(vi)They are deflected by electrical and magnetic fields just as the cathode rays but in opposite directions showing that they are oppositely charged, i.e., they carry positive charge. Since their deflection is very little, they consist of very heavy particles.

The coralloid roots of Cycas are symbiotically associated with nitrogen fixing blue-green algae, Anabaena cycadae and Nostoc punctiforme. In the middle cortex of coralloid roots, there occurs a broad blue green zone, which is known as algal zone. Coralloid roots are irregular, negatively geotropic, dichotomously branched coral like roots which do not possess root hair and root caps.

Red algae are different from other groups except for diatoms. Listed below are general characteristics of Red Algae.

• Lack of flagella and centrioles
• Presence of photosynthetic pigments
• Found both in marine and freshwater
• They show biphasic or triphasic life cycle patterns.
• They are a multicellular, filament, blade structure.
• Stored food is in the form of starch and polymers of galactan sulphate
• A pit connection (hole in the septum) is formed between two algal cells.
• Have a diffuse growth pattern- Apical growth, Complex oogamy (triphasic)
• These group of red algae is generally found in tropical marine locations
• The mode of nutrition may either be saprophytic, parasitic or also epiphytic.

Crusades were the holy wars that were fought between the Muslims and the Christians for taking control of the ancient holy sites. 

• It led to the decline of feudalism in Europe
• While fighting holy wars against the Turkish Muslims, the crusaders learnt the use of guns and gunpowder. This discovery greatly undermined the importance of feudal lords and armoured knights.
• It now became difficult for them to defy the authority of the king, leading to the decline of feudalism and the consolidation of the powers of the king. 
• When the Europeans went to Asia to fight crusades, they learned several new ideas from the Muslims. It also increased the desire for trade with other parts of the world. This lead to the rise of the merchant class and the end of serfdom.
• The crusaders in their fight with the Muslims came into contact with several manuscripts pertaining to the Roman and Greek culture. Thus, began the process of learning these cultures leading to the beginning of the Renaissance in Europe.
• As a result of the Crusades, direct trade contacts were opened between the East and West. Trade began to flourish and the European economy started to improve.
•  As traders, bankers and artisans began to pay taxes, the wealth and the power of the king improved.

Atomic or molecular chemical species having a highly localized HOMO (The Highest Occupied Molecular Orbital) act as Lewis bases. These chemical species have the ability to donate an electron pair to a given Lewis acid in order to form an adduct, as discussed earlier.

Examples of Lewis bases which have an ability to donate an electron pair are listed below.

• Pyridine and the derivatives of pyridine have the ability to act as electron pair donors. Thus, these compounds can be classified as Lewis bases.
• The compounds in which Oxygen, Sulphur, Selenium, and Tellurium (which belong to group 16 of the Periodic Table) exhibit an oxidation state of -2 are generally Lewis bases. Examples of such compounds include water and ketones.
• The simple anions which have an electron pair can also act as Lewis bases by donating these electrons. Examples of such anions include H^– and F^–. Even some complex anions, such as the sulfate anion (SO₄^2-) can donate pairs of electrons.

Lewis Acids are the chemical species which have empty orbitals and are able to accept electron pairs from Lewis bases. This term was classically used to describe chemical species with a trigonal planar structure and an empty p-orbital. An example of such a Lewis acid would be BR₃ (where R can be a halide or an organic substituent).

Some common examples of Lewis acids which can accept electron pairs include:

• H⁺ ions (or protons) can be considered as Lewis acids along with onium ions like H₃O⁺.
• The cations of d block elements which display high oxidation states can act as electron pair acceptors. An example of such a cation is Fe³⁺.
• Cations of metals such as Mg²⁺ and Li⁺ can form coordination compounds with water acting as the ligand. These aquo complexes can accept electron pairs and behave as Lewis acids.

The Islamic prophet Muhammad came to Medina following the migration of his followers in what is known as the Hijra (migration to Medina) in 622. He had been invited to Medina by city leaders to adjudicate disputes between clans from which the city suffered. He left Medina to return to and conquer Mecca in December 629.

An indifference curve is a graph showing combination of two goods that give the consumer equal satisfaction and utility. Each point on an indifference curve indicates that a consumer is indifferent between the two and all points give him the same utility.

Description: Graphically, the indifference curve is drawn as a downward sloping convex to the origin. The graph shows a combination of two goods that the consumer consumes.

The above diagram shows the U indifference curve showing bundles of goods A and B. To the consumer, bundle A and B are the same as both of them give him the equal satisfaction. In other words, point A gives as much utility as point B to the individual. The consumer will be satisfied at any point along the curve assuming that other things are constant.

Physical Fitness

• It is the capacity to do the work without any fatigue and after doing his work he has more power to do some more work.
• It is a combination of qualities that enable a person to perform well in vigorous physical activities.
• Physical fitness is the ability to perform the task effectively & efficiently.
• Being physically fit, a person can enjoy the leisure time, be healthy and emergency situations.

Wellness

• Wellness is the state of being healthy and free from all the diseases.
• It refers to man’s capacity of spending a good balanced life.