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The human evolution process is divided into following division:

1. Stone age
2. Copper
3. Bronze age
4. Iron age
5. Atomic age

(a) Odisha, Karnataka, Madhya Pradesh, Maharashtra, Goa

Being a tropical country, India has an abundance of sunlight. Hence, there are huge possibilities of tapping solar energy. Solar energy is a non-conventional source of energy, but it is gaining popularity in rural and remote areas whose households’ dependence on firewood and dung cakes is reduced as a result. This in turn helps in conserving environment and ensuring an adequate supply of manure in agriculture.

If both the characters present in F₁ generation pass together in F₂ generation, then garnets and offsprings would receive a double dose of information, that will be abnormal.

Mineral resources have played a large role in the human progress.

Correct option is (b) Mica

With time new inventions and developments keep on taking place in all the fields. This demands extraction and use of minerals: The world has become a global village. Every nation wants to grow it economy. So, the nations keep researching about the new products, manufacture them and export to earn foreign exchange. All these processes also put a very high stress on extraction of minerals.

Minerals and energy resources are available in limited quantity whereas we are increasing their use day by day. The future generations will not be able to use the mineral resources and the future of the world may be dark. Moreover, excessive use of these resources has polluted the environment to a very large extent and has deteriorated its quality. Hence, it is highly desirable to make sustainable use of energy to save the future of coming generations.

The network of computers around the world is called internet. Internet facilitates exchange of e-mails. Any information can be sent to any part of the world within a few seconds through e-mail. E-mail enables us to send a single message simultaneously to thousands of persons. Internet also enables to do video conferencing. Videoconferencing saves time and money and enables us to communicate through audio-visual medium.

(d) All of these

Your friend is absolutely right- There are two ways by which we can determine the age of fossils- 

(1) If we dig into the earth and start finding fossils, it is reasonable to suppose that the fossils we nd closer to the surface are more recent than the fossils wend in deeper layers. 

(2) By detecting the ratios of different isotopes of the same element in the fossil material.

This method is known as carbon dating

The ore from which aluminum is obtained is called bauxite. It is extract from earth and is purified to obtain aluminum. It was first found at Les Baux in 1921 in France and so it got the name Bauxite.

Properties and uses: Bauxite is very light in weight yet very strong and durable. It is a good conductor of electricity is rust-free and is easily ductile. These properties make it a very useful metal. It is widely used in the manufacturing household utensils, electrical wires and gadgets, colour and in shipbuilding.

Producing regions: Bauxite is obtained from Odisha, Chhattisgarh, Maharashtra, Jharkhand and Gujarat. It is found in the Deccan Traps which is a geological structure in the Deccan Plateau. It is found in abundance in Ranchi, Jharkhand. In Gujarat it is found in Jamnagar, Bhavnagar, Junagadh, Amreli, Surat and Sabarkantha districts.

(d) All are used to make electric wires.

Aluminium is extracted from Bauxite. It makes up about 8 per cent of the earth’s crust. It is light, strong and a very good conductor of electricity. It is largely used in various industries like transportation (aircraft, ship building, automobiles), chemical industries, electrical goods, machines, etc. It is used in making utensils, coins, furniture, sheets, packing material, photo-frames, pipes, etc. It is the basis of our telecommunication systems as it is used in radios, telegraphs, televisions and electrical wires. Due to its wide uses, it has been described as the ‘champion of metals’ or ‘the metal of the twentieth century’.

Pawanhans company provides helicopter services to ONGC.

We can find the relative of the fossil by the depth at which the fossil is found. The ones that are found near the surface are more recent than the fossils found in the deeper layer. The second way of dating fossils in detecting the ratios of different isotopes of the same element in the fossils material.

Platelets and WBC.

It is the arrangement of organism into series of groups based on the similarity of characters on physiology, anatomy, morphology and other relationships.

Chromosomes are thread-like structures, made of proteins and DNA, found in the nucleus at the time of cell division.
In sexually reproducing organisms, the gametes undergo meiosis, and hence, each gamete contains only half a set of chromosomes. When two gametes fuse, the zygote formed contains the full set of chromosomes. Hence, the formation of gametes by meiosis helps to maintain the number of chromosomes in the progeny.

Pericardial fluid acts as a shock absorber and protects the heart from mechanical injuries. It also keeps the heart moist and acts as lubricant.

Following are the differences between the artery and a vein:

Blood becomes oxygenated in the lungs. The oxygenated blood is returned to left verticles by the pulmonary vein.

Different forms of organisms have evolved during the course of evolution. Classification deals with grouping of these organisms into groups and subgroups based on their similarities and differences. The more characteristics any two species have in common more closely they are related. In other words, they will have a more recent ancestor.
Thus, classification helps tracing the evolutionary relationships between the two organisms. Hence classification and evolution are interlinked.

Platelets secrete platelet factors which are essential in blood clotting. They also seal v the ruptured blood vessels by formation of platelet plug/thrombus. They secrete serotonin, a local vasoconstrictor.

It is the exchange of genetic material by interbreeding between populations of the same species. Gene flow increases the variations in a population.

a. The two lower chambers of the heart are called ventricles.  

b. The pulmonary artery takes the blood from the ventricles to the lungs.  

c. The blood loaded with carbon dioxide from the body comes into the right auricle of  the heart.  

d. The oxygen-rich blood from the lungs comes into the left ventricle of the heart.  

e. The oxygen-rich blood is pumped into different parts of the body through aorta.  

f. The carbon dioxide loaded blood from right ventricle is pumped into the lungs  through pulmonary artery.  

g. The instrument used to find out the blood pressure is known  as sphygmomanometer.  

h. The colour of a red blood cell is due to haemoglobin.  

i. The blood plasma contains a dissolved substance called fibrinogen.  

j. The liquid part of coagulated blood is known as serum.

Characteristics are the hereditary traits transmitted from parent organisms to their offspring. These are details of appearance or behavior in other words a particular form or a particular function. It shows how closely organisms are related with respect to evolution. The more characteristics two species will have in common, the more closely they are related. And the more closely they are related, the more recently they will have had a common ancestor. 

For example, a brother and a sister are closely related. They have common ancestors in the first generation before them, namely their parents. A girl and her first cousin are also related, but less than the girl and her brother. This is because cousins have common ancestors, their grandparents in the second generation before them, not in the first one.

Neutrophils are responsible for destroying pathogens by the process of phagocytosis.

Erythrocytes carry oxygen to all cells of the body from the lungs and bringing carbon dioxide from all the cells back to lungs.

It is the transfer of genes from one population to another due to migration. Breeding between the brown and green beetles introduces new gene combinations into the population. 

Over generations, genetic drift will accumulate different changes in each sub population. Also, natural selection may also operate differently in the different geographic locations. 

Speciation due to inbreeding, genetic drift and natural selection will be applicable to all sexually reproducing organism.

(a) Lubb : Atrio-ventricular valve :: Dup : Semilunar valves

(b) Coronary artery : Heart :: Hepatic artery : Liver

It explains that organisms that are physiologically or behaviourally better adapted for the environment are selected. Selected organisms can survive and reproduce.

The epiglottis prevents the entry of food into the trachea by closing the glottis temporarily.

Ventilators used in hospitals are part of life supporting system, which help in breathing by 

1. Pushing oxygen into the lungs 

2. Removing carbon dioxide from the lungs

(b) renal artery

The blood vessel supplying blood to the kidney is Renal artery.

Speciation: It is an event that splits a population into two independent species which cannot reproduce among them.

• Process of speciation- 

Genetic drift: It occurs due to changes in the frequencies of particular genes by chance alone. e.g. If a hurricane strikes the mainland, and bananas with beetle eggs on them are washed away to an island. This is called a genetic drift.

natural selection: These are the variations caused in individuals due to natural selection which lead to the formation of a new species. e.g. If the ecological conditions are slightly different on the island as compared to the mainland, it leads to a change in the morphology and food preferences in the organisms over the course of generations.

splitting of population: A population splits into different subpopulations due to geographical isolation that leads to the formation of a new species.

Carbonic anhydrase enzyme is found inside the RBCs only to accelerate the rate of formation of carbonic acid from CO₂ and H₂O

1. In one normal heartbeat the heart sounds like lubb and dup are produced once each. 

2. The rhythmic contraction (Systole) and relaxation (diastole) forms are heartbeat. The heart sounds are due to closure of valves. 

3. Lubb sound is produced during ventricular systole when the cuspid valves close both the atrioventricular apertures preventing blood flow into atria. 

4. Dub sound is produced during ventricular diastole when semilunar valves are closed, preventing backflow of blood from pulmonary trunk and systemic aorta into ventricles.

Fibrous pericardium, parietal layer of serous pericardium and visceral layer of serous pericardium.

(i) Renal, 

(ii) Gonads (testis, ovary), 

(iii) Right sub-Calvin,

(iv) Diaphragm, 

(v) Hepatic, 

(vi) Inter coastal.

Cardiac Cycle: It is the sequential phenomenon of contraction and relaxation of heart. The action potential causes atria and then ventricles to undergo contraction (systole) followed by their relaxation (diastole). Systole forces blood to move from the atria to the ventricles and to the pulmonary artery and the aorta, then. The heart beats 72 times in a minute. So several cardiac cycles are done per minute. The duration of cardiac cycle is 0-8 seconds. Two heart sounds are heard by stethoscope during each cardiac cycle.

Species can be defined as a group of individuals of the same kind that can interbreed and produce fertile progeny.

It is an event that splits a population into two independent species which cannot reproduce among them.

All the life on Earth has descended from a common ancestor. Evolution is the sequence of gradual changes over millions of years in which new species are produced. Charles Robert Darwin was an English naturalist who observed various species of life on the earth and put forward the idea of “evolution of species by natural selection.” He said that a species inherits its characters from its ancestors.

Acquired and inherited traits:

An acquired trait is not transmitted to the off spring. In sexually reproducing organisms germ cells are produced in the reproductive organs, while the rest of the body has somatic cells. Changes in somatic cells due to environmental factors are not transmitted to the offspring.

This is because a change in a somatic organ caused by a physiological response by the body does not bring about a corresponding change in reproduction organs.

A trait or character that is genetically inherited or passed down from generation to generation is known as inherited trait. Hugo de Vries explained the mechanism of heritable variations.

According to him heritable variations arise when there is a change in the genes of the germplasm. He called it mutation. If a particular trait spreads in the population, it means that is favuored by natural selection.

Correct answer is (b) RBCs

The objective of setting up the Jawaharlal Nehru Port Trust at Navi Mumbai, South of Mumbai port was to reduce the pressure of traffic at the Mumbai Port. 

The virtual image formed by a convex lens will be magnified and upright.

On heating, ammonium salt dissociates into ammonia and HCl. The other property of ammonium salt is that when heated with alkali, NH₃ is formed.

NH₄Cl + NaOH → NaCl + H₂O + NH₃ 

Baking soda is a substance added to food for its faster cooking. Its chemical name is sodium hydrogen carbonate.

Uses: (i) It is used as an antacid to remove acidity of stomach.

(ii) It is used in fire extinguishers.

Baking soda is sodium hydrogencarbonate whereas washing soda is sodium carbonate decahydrate.

(a)Convex lens.

(b)Virtual.

Take about 50 cm³ of dilute sulphuric acid in a beaker and add 5 gm of zinc filings and heat it on a wire gauge with constant stirring. Zinc metal reacts with dilute sulphuric acid to liberate hydrogen gas and zinc sulphate is formed.

Zn + H₂SO₄  → ZnSO₄ (Zinc sulphate) + H₂ 

More zinc filings are added, till dilute sulphuric acid is completely consumed and effervescence of hydrogen stops. Filter the solution to remove undissolved zinc and collect the filtrate in an evaporating dish. Heat the solution till a saturated solution is obtained. Cool the solution to obtain the crystals of zinc sulphate with seven molecules of water of crystallization.

ZnSO₄ + 7H₂O → ZnSO₄ .7H₂O (Heptahydrate zinc sulphate)