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Coacervates probably provided a nitid separation between an internal and an external environment and thus the organic material within was not lost to the ocean. The enzymatic action inside that internal environment could develop in different manners increasing the speed of specific chemical reactions. Coacervates also allowed the molecular flux across its membrane to be selective. Since containing different molecules and differently organized from each other, coacervates could have promoted a competition for molecules from the environment setting out an evolutionary selection.

Ultraviolet radiation from the sun was not disallowed to reach the surface of the primitive earth. Therefore the development of life on dry land or even near the aquatic surface was impracticable. Probably the first living beings lived submerged in deep water to avoid destruction by solar radiation. Only after the appearance of photosynthetic beings and the later filling of the atmosphere with oxygen released by them the formation of the atmospheric ozone layer that filters ultraviolet radiation was possible.

3.5 billion years ago the water cycle was faster than today, resulting in hard storms with intense electrical discharges. There was also no chemical protection from the ozone layer against  ultraviolet radiation. The temperatures in the atmosphere and on the planet surface were very high. Electricity, radiation and heat constituted large available energy sources.

The presence of molecular oxygen in the primitive atmosphere was probably at a minimum and extremely rare. Oxygen became abundant with the emergence of photosynthetic beings, approximately, 1.5 billion years after the appearance of life on the planet.

The present atmosphere of the earth is constituted mainly of molecular nitrogen (N₂) and molecular oxygen (O₂). Nitrogen is the most abundant gas, approximately 80% of the total volume. Oxygen makes up about 20%. Other gases exist in the atmosphere in a low percentage. (Of great concern is the increase in the amount of carbon dioxide due to human activity, the cause of the threatening global warming.)

The earth's primitive atmosphere was basically formed of methane, hydrogen, ammonia and water vapor. 

The heterotrophic hypothesis is the strongest and most accepted hypothesis about the origin of life.

The spontaneous generation hypothesis has been excluded by the experiments of Pasteur. The panspermia hypothesis is not yet completely refuted but it is not well-accepted since it would be necessary to explain how living beings could survive long space journeys under conditions of extreme temperatures as well as to clarify the manner by which they would resist the high temperatures faced when entering the earth's atmosphere. The autotrophic hypothesis is weakened if one takes into account that the production of organic material from inorganic substances is a highly complex process requiring diversified enzymatic systems and that the existence of complex metabolic reactions on the primitive earth were not probable.

According to the heterotrophic hypothesis the first living beings were very simple heterotrophic organisms, i.e., not producers of their own food, which emerged from the gradual association of organic molecules into small organized structures (the coacervates). The first organic molecules in their turn would have appeared from substances of the earth's primitive atmosphere submitted to strong electrical discharges, to solar radiation and to high temperatures.

The autotrophic hypothesis on the origin of life asserts that the first living beings on earth were producers of their own food, just like plants and chemosynthetic microorganisms. 

To refute the spontaneous generation hypothesis many experiments were performed. Francisco Redi, in 1668, verified that maggots appeared on meat only when there was exposition to the environment; within closed environments, they did not appear. In 1862, Louis Pasteur working with swanneck flasks refuted the abiogenesis hypothesis definitively. In this experiment Pasteur demonstrated that boiled (to kill microorganisms) nutritive soups put in swan-neck flasks (with a curved down mouth so microorganisms could not enter easily) did not contaminate with microorganisms while the same soups within flasks with open upwards mouths were contaminated in a few days. The fact that both flasks were open refuted the argument of the vitalists that the vital elan could not enter the flasks. Pasteur broke the swan-necks of the flasks to demonstrate that proliferation of microorganism could happen if these beings were able to reach the broth.

(i) C. luteinizing hormone

(ii) B. Progesterone

(iii) C. There will be no observed data for Hormone B

(iv) A. Corpus Luteum

(v) D. 280 days

(vi) B) Subject 2 is pregnant

(i) d) All of the above

(ii) c) Both a and b

(iii) d) All of the above

(iv) a) Self-esteem

(i) C. Luteinizing Hormone

(ii) B. Progesterone

(iii) C. There will be no observed data for Hormone B

(iv) A. Corpus Luteum

(v) D. 280 days

(vi) B. Subject 2 is pregnant

Correct option is C. Due to failure of cytokinesis after telophase stage of cell division

[Hint : It lowers the melting point of the mixture and brings conductivity.]

Cryolite (Na₃AlF₆) has two roles in the metallurgy of aluminium:
1. To decrease the melting point of the mixture from 2323 K to 1140 K.
2. To increase the electrical conductivity of Al₂O_3.

[Hint : Examples are cresol and aniline.]

Cu = 25-30%, Zn = 25-30%, Ni = 40-50%]

The correct  answer   "   NaCN   '

Correct option is (b) (i)-3; (ii)-2; (iii)-1 

Concept:

Book value at the end of 1 years (BV1) = P - Pf = P (1 - f)

Book value at the end of n yrs (BV10) = p (1 - f)n

where, f = fixed percentage of the book value

D = Depreciation = pf

P = Purchasing value

Calculatio:

Given:

Purchased value = P = 100,000/-

Life time of product = n = 10 yrs

Scrap value after 10 yrs (BV₁₀) = 20,000/-

Using declining balance method

Let; f = fixed percentage of the book value

So, D = Depreciation = Pf

∴ Book value at the end of 1 years (BV₁) = P - Pf = P (1 - f)

Similarly;

Book value at the end of 10 yrs (BV₁₀) = P (1 - f)ⁿ

⇒ 20,000 = 100,000 (1 - f)¹⁰

⇒ f = 0.149

Now,

BV₁ = P (1 - f)

= 100,000 (1 - 0.149)

= 85,100

So value of depreciation during first year = 100000 - 85100 = 14900

Correct option is (d) Neither on Debit nor on Credit side

Correct option is (c) ₹10,000 

Correct option is (a) ₹ 4,00,000 

Correct option is (c) ₹30,000

Correct option is (b) ₹16,00,000 

Correct option is (c) ₹1,34,000 

Quantity A:

E and F together fill a cistern in 30 minutes.

Pipe E alone can fill it in 45 minutes

Time taken by F alone to fill cistern

Calculation:

Cistern filled in 1 minute by E and F = 1/30

Cistern filled by E in 1 minute = 1/45

Time taken by pipe F alone to fill a cistern = [(1/30) – ( 1/45)]

= [( 3 -2)/90]

= 1/90 = 90 minutes

Quantity B:

90 minutes

∴ Quantity A = Quantity B

Amount=9680 and interest is 1680

Given:

Amount of investment of Pramod = Rs. 50,000

Amount of investment of Amit = Rs. 1,20,000

Time period of investment of Pramod = 12 months

Time period of Amit = 5 months

Concept used:

Ratio of their profit will be proportional to the (Amount × Time period of investment)

Calculation:

Ratio between the investment of Pramod and Amit =

 ⇒ (50,000 × 12) : (1, 20,000 × 5)

 ⇒ 6,00,000 : 60,000

⇒ 1 : 1

∴ The ratio of profit divided between them is 1 : 1

Given:

Investment amount ratio of P, Q and R respectively = 5 : 4 : 10

Investment rates(compounded annually) of P, Q and R = 20%, 25% and 10%

Calculation:

According to the question,

Let the investments amounts of P, Q and R be 5x, 4x and 10x

Amount after 1 year for P = 5x(1.2) = 6x

Amount after 1 year for Q = 4x(1.25) = 5x

Amount after 1 year for R = 10x(1.1) = 11x

∴ Ratio of amounts after 1 year of P, Q and R = 6 : 5 : 11

Given:

Amounted invested by A = Rs. 4,50,000

Amount invested by B = Rs. 2,00,000

Amount invested by C = Rs. 6,00,000

Calculation:

4,50,000(t) : 2,00,000(t – 5) : 6,00,000(t – 5 – 3) = 27 : 7 : 12

⇒ [(450,000 t/(2,00,000)( t – 5)] = 27/7

⇒ [(9t/ 4t – 20)] = 27/7

⇒ 63t= 108t - 540

t = 12 months

B invested for 7 months [(i.e. 12 – 5)]

C invested for 4 months [(i.e. 12 – 5– 3)]

Given:

⇒ Increment in the price = 25%

Formula Used:

Total Cost/Per kg cost = Weight (Kg of Maize)

Calculation:

Let assume that original price for 1 kg Maize = Rs. x

⇒ Increased price for 1 kg Maize = 125x/100 = Rs. 5x/4

According to question:

Total Cost/Per kg cost = Weight (Kg of Maize)

⇒ 2400/x – 2400/(5x/4) = 5

⇒ 2400 × (1 – 4/5) / x = 5

⇒ 2400/5x = 5

⇒ x = 96

⇒ So, original price = Rs.96

⇒ And increased price = Rs. 96 × 5/4 = Rs. 120

∴  The increased price per kg = Rs. 120.

The correct option is 2 i.e. Rs. 120

Laura got up to go home. She was supported by her maid. She turned her head and was surprised to see Gonzalo picking up the violets which had been droped on the ground.

Soli Sorabjee

The children wanted to know from their mother who that lady was. The mother replied that she was a close friend who was very dear to her. The children asked their mother why she had never told them about her. The mother replied that when the time came, they would know everything.

Dona Laura asked Don Gonzalo if he used a handkerchief as a shoe brush. When Don Gonzalo reported why he shouldn’t, Dona Laura further asked if he used a shoe brush as a handkerchief. Don Gonzalo asked angrily what right she had to criticize his action. Dona Laura replied that she had the right of a neighbour.

Correct answer is Delhi

The reporter congratulated Sachin since he then had another world record to his credit. Sachin acknowledged that God was great and he added that he only enjoyed his cricket. The reporter further asked what would be the next record after 200 not out in an ODI. The reporter wondered if they could hope for 400 plus innings in a test match. Sachin replied that he would try his best.