Soluti-On

(1) Maturation of anther (stamen) and stigma (carpel) at different times is called dichogamy. (2) Dichogamy is of two types, viz, protandry and protogyny. (3) Maturity of anthers before that of gynoecium is protandry and maturity of carpel before Maturity of pollen grains is protogyny. (4) As this forms barrier for self-pollination, dichogamy favours cross pollination.

(1) Fertilization is fusion of male and female gametes. (2) Pollination is transfer of pollen grains which carry non-motile male gametes. (3) Pollen grains are transferred from anther to stigma of flower where they germinate. (4) Both male and female gametes are non- motile and they are produced at two different sites. (5) Therefore the pollination process is necessary for act of fertilization in plants.

(1) Embryo sac develops inside the nucellus of ovule from megaspore. (2) Megaspore mother cell is diploid structure which undergoes meiosis. (3) After meiosis. tetrad of haploid cells are produced. (4) The upper three megaspores degenerate and the lower one of the tetrad is functional. (5) The entire embryo sac is developed by elongation and then three mitotic divisions of this single megaspore take place hence the development is described monosporic.

Schottky defect - 1) In ionic solid, equal number of cations and anions are missing from their regular positions creating vacancies. 2) Thus there exist two holes er ion pair lost, one due to missing cation and other due to missing anion. This paired cation anion vacancy defect is a schottky defect. 3) Conditions for formation of Schottky defect- Schottky defect is found in ionic compounds having- i) high degree of ionic character. ii) high coordination number of anion iii) small difference between the size of cation and anion (FT is not far below unity) 4) Consequences of Schottky defect- anton i) Density of substance decreases. ii) Electrical neutrality bi s maintained. e.g. NaCl. AgBr, and KCI.

Composition of vapour in equilibrium with the solution can be determined by Dalton's law of partial pressures If y1 and y2 are mole fractions of two components in the vapour, then P1=y1P and P2= y2P. where P and P, are the partial pressures of two components in the vapour and P is the total pressure.

Raoult's Law : It states that, "The partial vapour pressure of any volatile component of a solution is equal to vapour pressure of pure component multiplied by its fraction in the solution." Consider a solution of two components A, and A2. Mole fractions of A, and A are x and x2 respectively. Let P and P are the vapour pressures of A, and A, respectively. Then according to Raoult's law, the partial pressure P and P₂ of two components are P₁ = P°x P₂ =P°x Total vapour pressure is P. P=P+P₂ P = P °x + PX2 X₁ = 1-X2 putting this value in above equation P(1-x)+ Px= P - P° x2 + P₂ x2 P= (P-P) x2+ P

This is because haemoglobin in the blood reacts with oxygen as follows Hb + 402 → Hb(O2)4 Therefore solubility of oxygen in the blood increases. Oxygenated blood is pumped to various parts of the body for supply of oxygen .

Henry's Law : It states that the solubility of gas in a liquid at constant temperature is proportional to the pressure of gas over the solution. S~ P S=K₁P Where KH = Henry's constant. Its unit is mol dm3 bar When P = 1 bar then S = KH. Henry's constant: It is defined as solubility of gas in a liquid when its pressure over the solution is 1 bar. e.g. Consider a sealed soft drink bottle. Due to high partial pressure of carbon dioxide the amount of CO₂ is in dissolved state. When the cap is removed the excess of CO2 and air escape. Thus, by releasing pressure, solubility of CO2 is decreased. Exceptions to Henry's law- The gases like NH3 and CO2, which react with water do not obey Henry's law. They have higher solubilities than expected by Henry's law. NH3+ H2O-→→→→ NH, + OH CO₂+ H2O →→ H₂CO3

Solubility - The solubility of solute is its amount per unit volume of saturated solution at a specific temperature. Unit of solubility is mol/L. Factors affecting solubility of solute in liquid solvent.  1) Nature of solute and solvent- i) Solubility of solute in a solvent is explained as "like dissolves like. It means that compounds having similar chemical characters are readily soluble in each other. iii) Nonpolar organic substance dissolves in nonpolar solvent. E.g. Cholesterol in benzene. iv) Sugar dissolves in water due to intermolecular Hydrogen bonding. 2) Temperature: i) Generally solubility of solid in liquid increases with increase in temperature.  ii) Dissolution of some substances in water is exothermic process. Solubility of such substances is increased by decreasing temperature. It means they are more soluble in cold water. e.g. CaCl2, Na2SO, etc., iii) Dissolution of some substances in water is endothermic process. Solubility of such substances is increased by ...

Depending upon the amount of solute present in the solution it is classified into three different classes. They are as follows: 1) Saturated solution : It is defined as the solution that contains maximum amount of solute dissolved in a given amount of solvent at a given temperature. In saturated solution dynamic equilibrium is established between dissolution and crystallization processes. 2) Unsaturated solution : It is a solution containing less amount of solute than required for forming saturated solution. 3) Supersaturated solution : A solution containing greater than the equilibrium amount of solute is called supersaturated solution. Such solutions are unstable.

Solution : A solution is defined as homogeneous mixture of two or more pure substances.  Classification of mixtures on the basis of sizes of the components - Solutions are mixtures of two or more components. Depending on sizes of the components, the mixtures are classified into two types: a) A colloidal dispersion : It is formed when sizes of particles dispersed in solvent are in the range of 1 to 1000 nm. E.g. ferric hydroxide sol, arsenic sulphide sol. b) A true solution : It is obtained when particle size is very small. It is in the order of 0.1 to 1 nm e.g. aqueous sugar solution or aqueous NaCl solution.

Hypotonic solutions : When two solutions have different osmotic pressures, then the solution having lower osmotic pressure is said to be a hypotonic solution with respect to the other solution.

Point defect: The defect or imperfection produced in the arrangement of a point like constituent particle, e.g. an atom or an ion or a molecule in the crystalline structure is called point defect. The point defects are classified as follows: (1) Vacancy defect. (2) Interstitial defect. (3) Impurity defect.

AB4  A3B  AB  AB3  Solution:- A3B

Metallic crystal  Covalent crystal  Ionic crystal Molecular crystal Solution:- 2. Covalent Crystal  

Polymorphous  Amorphous Isomorphous Monomorphous Solution:- 1.Polymorphous  

a. r=√3/4 a  b. r= a/2√2 c. r=a/2 d. r=2√2 Solution:- b. r= a/2√2

a. 2 b. 4 c. 6 d. 8 Solution:- d. 8

a.Crystalline solids  b.Amorphous solids  b.Ionic solids  c.Metallic solids  Solution:- b. Amorphous solids 

Edit document   Monitor change   Track changes  Track all  Answer:- 3.Track Changes is used to monitor all documents. 

Maharshtra State Board Class 12th Physics 2023: Practical Book & Solutions ; Download  Get free download Maharashtra state board class 12th physics 2023 Practical Book solutions by one click. All practical solutions are in only one pdf. Just download the single pdf for all practical and activities solutions.  If you are preparing for jee main or jee advanced, we have given previous year questions in our last blog. If you want to download it you can download it by click on visit now .  If you like the information which we have shared with you share it with your class 12th friends and please comment your opinion on our site. And you can also suggests us for our improvement.  Physics Practical Class 12th Solutions PDF Download  Subject Name Solutions PDF Physics Download

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To convert phenol into picric acid the nitric acid in presence of Conc. H2SO4 is used.  And to convert phenol into p-benzoquinone chromic anhydride or sodium dichromate in presence of Conc. H2SO4 is used. 

Conversion of phenol to salicylic acid is called as kolbe's Reaction. In this reaction phenol is treated with NaoH and we get sodium phenoxide. And when sodium phenoxide is treated with co2 at 398 K under the pressure of 6 atm. We get sodium salicylate and when sodium salicylate reacts with h3o+ it gives salicylic acid. 

98 percentile in jee mains means you have to score more than 170 marks out of 360 marks. And marks and percentile relation is also depends on your shift also. Because if your shift has easy paper than you have to score more marks for good percentile. 

If you want to score 99 percentile in jee main then you want to score minimum 180 or 180+ in your shift. In jee main the percentile is totally depends on the shift in which you give paper. So if your paper is hard and you scored more than 150 or 180 that is much enough to get 99 percentile.

Closed circulation considerably enhances the speed, precision and efficiency of circulation.  The blood flows more rapidly, it takes less time to circulate through the closed system and return to the heart.  This fastens the supply and removal of materials to and from the tissues by the blood as compared to open circulation.  In open circulation, there are no blood vessels such as arteries or veins, to pump the blood.  Therefore, the blood pressure is very low.  Organisms with an open circulatory system typically have a relatively high volume of hemolymph and low blood pressure. Closed circulation is thur more efficient than open circulation. 

Transgenic mice are used in various reasearch areas of cancer research.  Transgenic mice containing a particular oncogene (cance causing gene) develop specific cancer.  They are used to study the relationship between oncogenes ans cancer development. Cancer treatment and prevention of malignancy.  The transgenic mouse model for the investigation of the breast cancer was developed in the laboratory of Philip leder in Harvard (USA).  Transgenic mice containing oncogenes myc and ras were analysed to find out the role of these genes in the development of breast cancer. 

Atmosphere is the reservoir of carbon cycle. While fossil fuels embedded in ocean and oceanic waters are the sink of carbon in carbon cycle. 

Oceanic ecosystem has inverted pyramid of biomass

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Isolation of DNA :- The DNA can be isolated even from the small amount of tissue like blood, hair roots, skin etc.  Restriction digestion :-  the isolated DNA is treated with restriction enzymes which cut the DNA at specific sites to form small fragments of variable lengths.  Variations in the length of restriction fragments are known as restriction fragment length polymorphism.  Gel electrophoresis :-  the dna samples are loaded on agarose gel and electrophoresis is carried out.  Negatively charges DNA fragments move to the positive pole.  Separation of fragments depends on their length and it results in formation of bands.  Thus, dna is then denatured in sadna by alkali treatment.  Southern blotting :-  the separated dna membrane or a nitrocellulose membrane.  It is obtained from organisms or prepared by cDNA preparation method.  The dna probe is labelled with radioactive isotopes.  Hybridization :-  in this process...

  D-block Elements or transition metals and their compounds act as catalysts.  These catalysts are either homogeneous or heterogeneous.  Applications or uses of transition metals as catalysts: MnO2 : It is used as a catalyst in the decomposition of KCLO3 to O2  Platinised asbestos: It is used as a Catalyst in the preparation of H2So4, by oxidising So2 to So3. 

The following factors affect Ionization Enthalpy:-  The Force of attraction between nucleus and electrons.  Size of atom.  Effective nuclear charge.  Electronic Configuration.

Niche:- the processes about how that organism is linked with its physical and biological environment are called niche.  Habitat:- the physical space of an organism with other living or nonliving factors is called habitat . 

Medulla oblongata is the region of the brain that controls all the involuntary activities.  Vital activities such as heartbeats, respiration, vasomotor activities, peristalsis, etc. Are under the control of medulla oblongata.  When medulla oblongata is injured, all these vital functions are instantly stoped.  Therefore, injury to medulla oblongata causes sudden death. 

  Malleus (hammer), incus (anvil) and stapes (stirrup). 

  Melatonin .

  Progesterone . 

Terestosterone is a steroid sex hormone secreted by testes and cortex of adrenal glands. It controls the secondary sexual characters in males. 

Polydipsia, i.e. frequent thirst and polyuria, i.e. frequent urination are the Symptoms of the disease caused by hyposecretion of ADH.

Cerebellum of brain is an important centre which maintains equilibrium of body, posture , balancing orientation, moderation of voluntary movements and maintenance of muscle tone. 

Answer:- Corpora quadrigemina consists of 4 solid rounded structures, viz. Superior and inferior colliculi. Superior colliculi control visual reflexes while inferior colliculi control auditory reflexes. 

 Answer:-     Red nucleus plays an important role in controlling posture and muscle tone, modifying some motor activities and motor coordination. 

Arteries have relatively thick walls to enable them to withstand the high pressure of blood ejected from the heart.  Arteries expand when the pressure increases as the heart pushes blood our but then recoil when the pressure decreases when the heart relaxes between heartbeats.  This expansion and recoiling occurs to maintain a smooth blood flow.  Veins, on the other hand, have thinner walls and larger lumen-veins have no need for thick walls as they need not have to withstand high pressure like arteries.  Moreover, as veins transport relatively low Pressure blood, they are commonly equipped with valves to promote the unidirectional flow of blood towards the heart.

Left ventricle pumps oxygenated blood to all parts of body. Therefore, there is greater pressure from the blood in left ventricle.  Right ventricle sends deoxygenated blood to lungs for oxygenation. This does not put more pressure and lungs are in vicinity of the heart.  Due to these functional difference between the two ventricles, left ventricle has thicker wall than of right ventricle.