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(a) Single Buyer: Monoposony is a market structure where there is only one buyer of a commodity, service or input. It is a case of only one firm purchasing the entire product or factor service. 

(b) Single Seller: Monopoly is a market situation where there is only one seller or producer, called monopolist of a commodity. It is a case of one firm or producer controlling the supply of the product. Since there is only one seller, any change in the amount of output produced by the monopolist would have significant influence over the market price. Because there is only one firm in monopoly, therefore the difference between the firm and the industry disappears.

Monopsony : is the market situation in which there is a single buyer who purchase the whole commodity. Sellers may be one, few or in large numbers. This situation is very rare in the market.

For example—A coal mine may be the only employer who demands the services of coal-mines in a region.

One feature of a monopoly market in a monopolistically competitive market is that to differentiate their products, different sellers sell their products under different brand names. It is this which gives an individual firm some monopoly of its own differentiated product—its own brand name. This is monopoly component of monopolistic competition.

Supply refers to the quantity of a commodity that a seller is willing to sell corresponding to a given price, at a given point of time. On the other hand, elasticity of supply measures the degree of responsiveness of the quantity supplied of a commodity to a change in its price. It measures the sensitivity of the quantity supplied to a change in the price.

(a) Commercial bank is a financial institution which deals in money i.e. borrowing and lending of money. It performs the functions of accepting deposits from the general public and giving loans for investing to them with the aim of earning profit. 

The three methods adopted by commercial banks to mobilise funds from the public are as under: 

1. Cash Credit: In cash credit, the bank advances a ‘cash loan’ upto a specified limit to the customer against a bond or other security. A borrower is required F to open a current account and bank allows the borrowers to withdraw upto the full amount of the loan. The interest is charged only on the amount actually utilized by the borrower and not on the loan sanctioned. 

2. Loans: A loan is granted against some kind of security of assets or personal security of the borrower and the interest is charged on the full amount sanctioned as loan, irrespective of the fact whether full amount or part of it has been used. In case of loans, the borrower is provided with the facility to repay the loan in installment or as a lump-sum. 

3. Overdraft: The overdraft facility is allowed to the depositor maintaining a current account with the bank. According to this facility, a borrower is allowed to withdraw more amount than what he has deposited. The excess amount so withdrawn has to be repaid to the bank in a short period and that too with interest. The rate of interest is usually charged more than that charged in case of loans. However, the overdraft facility is given only against security of some assets or on personal security of the customer. 

(b) Advantages of division of labour: 

1. Reduction in Cost of Production: The specialised worker with the help of machines, produces, more quantity of goods in less time and with minimum wastage. This reduces the cost of production thereby resulting in more profits to the producer. 

2. Improvement in Quality: As the worker acquires greater skill in performing the work, the quality of the commodity produced is better. Quality product leads to increment in overall turnover and net profit of the producer. 

3. Increase in Production: With the division of labour, the workers become more skilled and efficient. They acquire higher speed in work which ultimately results in more production quantitatively and qualitatively. 

4. Economy of Large Scale Production: With the help of the division of labour, the commodities are being produced on large scale and in an efficient and quick way. This results in all kinds of interned and external economies for the production units. As such the cost of production is reduced and simultaneously, the quality of manufactured goods is improved. This ultimately yields more profit to the producer. 

5. Utilisation and Employment of Unskilled Labour: Due to simplification and bifurcation of complex processes into several small tasks, even the less skilled workers can be employed to perform these tasks. This reduces the cost of production on account of lower wages of an unskilled or semi-skilled worker. In addition, this increases overall employment in the country.

Accounting Cost: This is the actual, numeric dollar amount that a firm (company) pays to run their business. 

Opportunity Cost: This is the cost of choosing one thing over another.

(a) “The rise in price level after the point of full employment is true inflation.” —JM. 

KEYNES— 

In simple words, inflation is a situation in which prices of goods and services constantly rise, at a fast pace. 

The cause of inflation are as follows: 

1. Increase in Population: Increase in population refers to increased demand of consumer goods which puts a pressure on existing supply of goods and service thus resulting in inflation. 

2. High Rate of Investment: The heavy investments made by the Government as well as private industrialists have resulted in continuous increase in the prices of capital goods and other items of production.

3. Increase in Income: With the increased income of the people, rises the demand for their goods and services and hence their prices also increases. 

4. Enhanced Taxation: With every year budget, the Government imposes fresh commodity taxes, where the tax payers can easily shift the tax. It leads to increase in prices of different commodities, which in turn push up their prices. 

(b) Quantitative Credit Control: Quantitative Credit control are traditional methods which aims at controlling the cost and quantity of credit. Quantitative credit control methods influence the availability of credit indiscriminately. Bank rate, open market operations, cash reserve and statutory liquidity ratio are the methods of Quantitative Credit Control. Quantitative Credit Control Measures of the Central Bank 

1. Open Market Operations: It refers to the purchase or sale of Govt, securities, public securities, etc. in an open market by the central bank. In case of inflation, central bank sells securities on which buyer’s draw cheques from their A/c’s which reduces the cash reserve of the commercial banks. This reduces the power to create credit thereby commercial banks have to reduce their advance and loans and vice-versa in case of deflation. 

2. Cash Reserve Ratio (CRR) and Statutory Liquidity Ratio (SLR): 

Cash Reserve Ratio (CRR) refers to that percentage of total deposits of commercial bank which it has to keep with the RBI in the form of cash reserves. Statutory Liquidity Ratio (SLR) refers to that portion of the total deposits of commercial bank which it has to keep with itself in the form of cash reserves, gold and govt, securities. This is in addition to CRR. In case of inflation, the central bank increases the CRR and SLR which restricts the credit-granting capacity of the commercial banks and vice-versa in case of deflation.

The propensity to consume means the proportions of total income or of in increase an income that consumers tend to spend on goods and services rather than save.

Law of Equi-marginal utility states that the consumer in order to maximize his satisfaction should spend his money on two goods in such a manner that the ratio of marginal utility of a commodity to its price becomes equal to the ratio of marginal utility of other commodities to its price. Symbolically,

MU_x / P_x = MU_y/P_y = MU_n/P_n

The following precautions are to be taken while measuring National Income by Income Method : – 

-Transfer earning should not be included in National income, such as old age pensions, unemployment allowances, pocket money, scholarship etc. (because they don't contributes in production process). 

– Income form illegal activities should not be included in the National income such as smuggling, theft, gambling etc. (Because they are illegal). 

Accounting Cost: The costs which are known by profit and loss account of the firm are called accounting costs. 

Opportunity Cost : The cost of next best alternative forgone is called opportunity cost. 

Under perfect competition, AR or price remains fixed. So. MR will always be constant.

Two precautions to be taken while calculating national income by income method are as follows: 

(a) Transfer incomes such as pension and unemployment remittances should not be considered as income and should not be included in the calculation of national income. Only income earned by providing productive services must be included in the calculation of national income. 

(b) The sale and purchase of second-hand goods should not be included in the calculation of national income by income method. This is because such goods are not a part of production in the current year. However, the commission earned through a trade of such goods is included in national income as the commission is income earned through productive services rendered in the current year.

Fiscal measures to correct deficient demand in an economy are discussed below: 

(1) Increase in government spending: Government spends money on public works that include infrastructural activities and administrative activities. To rectify deficient demand, the government should increase expenditure on public works such as the construction of highways, flyovers and buildings. Such expenditures increase employment opportunities and provide additional income to people. Increasing public expenditure will help to increase aggregate demand and correct the situation of deficient demand.

(ii) A decrease in taxes: Government collects revenue from people in the form of taxes. Higher taxes imply lower disposable income and lower ability to spend. Thus, to rectify the situation of deficient demand, the government can lower taxes, which help in increasing people’s disposable income. As a result, the ability to spend money goes up and the aggregate demand is likely to increase.

Increasing returns to a factor occur because of the following factors: 

1. Fuller Utilisation of the Fixed Factor: In the initial stages, fixed factor (such as machine) remains underutilised. Its fuller utilisation calls for greater application of the variable factor (Labour). Hence, initially (so long as fixed factor remains underutilised) additional units of the variable factor add more and more to total output, or marginal product of the variable factor tends to increase.

2. Division of Labour and Increase in Efficiency: Additional application of the variable factor (Labour) enables process based division of labour. Specialised workers may be used for different processes of production. This increases efficiency or productivity of the variable factor. Accordingly, marginal productivity tends to rise.

3. Better Coordination between the Factors: So long as fixed factor remains underutilised, an additional application of the variable factor tends to improve the degree of coordination between the fixed and variable factors. As a result, marginal product (MP) increases and total product (TP) increases at the increasing rate.

Full employment: It is a situation in which all those people who are willing to work at the prevailing wage rate get work.

Involuntary unemployment: Involuntary unemployment is a situation in which people are able to work and willing to work at existing rate of wages but do not get work.

APC can be > 1 in situation when C > Y

(i) Price of the Commodity: There is a direct relationship between price of a commodity and its supply. Generally, higher the price, higher the quantity supplied, and lower the price, lower the quantity supplied.

(ii) Price of Related Goods: The supply of a good depends upon the price of related goods. For example: Consider a firm selling tea. If price of coffee rises in the market, the firm will be willing to sell less tea at its existing price. Or, it will be willing to sell the same quantity only at a higher price.

(iii) Number of Firms: Market supply of a commodity depends upon number of firms in the market. If there is increase in the number of firms market supply will increase and if the number of firms decreases market supply will fall.

(iv) Goal of the Firm: If goal of the firm is to maximise profits, more quantity of the commodity will be offered at a higher price. On the other hand, if goal of the firm is to maximise sales (or maximise output or employment) more will be supplied even at the same price.

Marginal Propensity to Consume refers to the ratio of change in consumption to change in income.

Symbolically,

\(MPC =\frac {Δc}{ΔY}\)

where ΔC refers to change in total consumption ΔY refers to change in income.

Marginal Propensity to Save, on the other hand, is the ratio of the change in total desired saving to change in total income.

Symbolically,

\(MPC =\frac {Δc}{ΔY}\)

where ΔS refers to change in total desired saving ΔY refers to a change in income.

Average Propensity to consume (APC):

“The ratio of total consumption to total disposable income of economy is known as average propensity to consume.” The amount of APC represents that how much part of income is consumed by the consumers of economy.

APC = C/Y 

Here , APC = Average Propensity to Consume

C = Total Consumption

Y = Total Income

Average Propensity to Save (APS) :

It means the ratio of Total Saving to Total Income. In other words when we divide Savings by Income , we get Average Propensity to Save.

APC = S/Y

Here , APS = Average Propensity to save

C = Total Consumption

Y = Total Income

Relationship between APC and APS

The sum of the average Propensity to Consume (APC) and Average Propensity to save (APS) is always equal to unity. i.e., APC + APS = 1. It is so because the money income can either be spent on consumption or it can be saved. In case, we consider the ratio of consumption to money income, we call it average propensity to consume, (APC), and the ratio of saving to income represents average propensity to save (APS). It is for his reason that the sum of APC and APS equals unity. Symbolically,

APC = C/Y and APS = S/Y

We know that Y = C + S

APC = APS = C/Y + S/Y = C+S/Y = Y/Y = 1

Here APC + APS = 1 

Income tax is a direct tax and Expenditure tax is a indirect tax. Tax imposed on receipt of income are called direct tax, for example income tax. Taxes which are imposed on expenditure incurred on commodity are regarded as indirect tax.

Eeconomic welfare 

The level of prosperity an equality of living standards in an economy. It can be measured through a variety of factors such as GDP and other indicators which reflect the welfare of populations. Such as literacy, level of pollution etc.

If the GDP of a country increases, welfare of the people of that country also increase since increase in GDP implies increase in per capita real income, i.e., increase in per capita availability of goods and services. Thus, higher level of GDP of a country may be treated as an index of economic welfare. However, this does not always happen. There are certain reason or limitations why GDP cannot always be taken as a perfect index of economic welfare. 

Fixed deposits: A lumpsum is deposited for a fixed time period. These deposits are repayable on the expiry of the stated period. Generally, the time period varies from three months to five years. The rate of interest on these deposits is higher than other deposits.

Demand deposits: Demand deposits are deposits which can be withdrawn at any time by the account holder. Current account deposits are included in demand deposits. In this interest is not given to the account holder. There is no restriction on amount of withdrawal and number of withdrawal.

Money is an instrument that serves as: 

• a medium of exchange 

• a measure of value 

• a store of value 

• a standard for deferred payments.

Functions of Money:

1. Medium of exchange: Most important function of money is as a medium of exchange to facilitate transactions. Without money, all transactions would have to be conducted by barter, which involves direct exchange of one good or service for another. Money effectively eliminates the double coincidence of wants problem by serving as a medium of exchange that is accepted in all transactions, by all parties, regardless of whether they desired each other’s goods and services. Use of money has separated the process of sale and purchase.

2. Store of value: In order to be a medium of exchange, money must hold its value over time; that is, it must be a store of value. If money could not be stored for some period of time and still remain valuable in exchange, it would not solve the double coincidence of wants problem and therefore would not be adopted as a medium of exchange. As a store of value, money is not unique; many other stores of value exist, such as land, works of art, and even baseball cards and stamps. Money may not even be the best store of value because it depreciates with inflation. 

However, still, money is used as a store of value as:

• It is more liquid than most other stores of value. 

• It is readily accepted everywhere. 

• It is easy and economical to store as its storage does not require much space.

3. Unit of account: Money also functions as a unit of account, providing a common measure of the value of goods and services being exchanged. Knowing the value of the price of a good, in terms of money, enables both the supplier and the purchaser of the good to make decisions about how much of the good to supply and how much of the good to purchase.

In the absence of the common measure, the seller has to express the value of his good in all other goods. 

For example: if you want to sell your horse you have to express its value.

1. Horse = 2 cows 

1. Horse = 5 bags of wheat 

1. Horse = 20 kg of iron

4. Standard of deferred payment:

(i) Money is accepted as a standard of deferred payments because:

• its price remains relatively stable compared to other commodities, 

• it has the merit of general acceptability, 

• it is more durable compared to other commodities.

It is because of this function of money that there has been a significant expansion of trade.

(ii) Using money as a standard of deferred payments is a direct consequence of the unit of account and store of value functions of money. 

(iii) Serving as a standard of deferred payments, money has stimulated the process of capital formation. It is because of this function of money that there has been a considerable growth of the money market as well as the capital market.

Roberston defined money as “anything which is widely accepted in payment for goods, or in discharge of other kinds of business obligations.”

Money is any object or reward that is generally accepted as payment for goods and services and repayment of debts in a given socio-economic context. The evolution of money has proved to be an unending and continuous process which can be seen from the fact that apart from the commodity money and metallic money, lately there is an emergence of paper money and a variety of other financial instruments. Money was brought into existence to over come the difficulties of barter, but in the process it has helped Economy in such a manner that its use has become indispensable. It has helped the economy in acquiring those complex features without which the latter could not develop.

Money perform its role as a:

1. Medium of Exchange: This medium of exchange function is one of the most important and oldest functions of money. Money works as a medium of exchange. Money has a generalized purchasing power. Money is used as medium of exchange; where it is earned by selling ones goods and services and used to buy another set of goods and services. 

2. Store of Value: Money serves as a store of value because it is easy to spend and easy to store. By performing the function of store of value, the money provides security to individuals to meet unpredictable contingencies and to pay debt that are in terms of money. Money has a unique nature of durability and stability in value; thus it can be stored for a long time. This has introduced in people, a trend of making savings from the incomes for future purposes.

Bank Rate: is the rate at which central bank rediscounts the first class bills of exchange of commercial banks. Simply speaking it is the rate of interest at which central bank lends money to the commercial banks. It is used as an instrument of the credit control policy of the central bank.

Chipko movement is related to forest conservation. The villages in Gharwal started this movement. Sunderlal Bahuguna, Amrita Devi etc., were the leaders for this movement and it gained momentum under their guidance. The aim was to protect the trees from cutting and felling. The people in great number hugged the trees so as to protect them from cutting. They embraced the trees. Chipko means embrace. This movement prevented contractors from cutting the trees. This became a turning point in the history of eco development. Many people lost their lives in this movement. This movement encouraged planting of trees for timber, food, shelter and making villages self-sufficient.

Avery, McLeod and McCarty’s experiment: 

From heat-killed S strain bacteria, extraction and purification of proteins, DNA and RNA, etc., is done.

The extract was treated with protease, RNAse and DNAse. DNAs treated extract did not kill mice. Protease killed mice. RNAse killed the mice.

This proved that DNA is the genetic material.

Significance: Hereditary material can be extracted from one organism and introduced into another (transformation).

Hence, DNA is transforming principle.

Wobble effect: The wobble effect is an effect caused by the redundancy found in the genetic code. Each amino acid is coded by a 3 nucleotide sequence on the wRNA. The triplets are referred to as codons. Though there are only 21 amino acids, 61 of the 64 possible codons found on the mRNA code for amino acids (the other 4 codons signal translation stop and start points). Thus, each amino acid can be coded by more than one codon. For any amino acid, the first 2 nucleotide’s in the codon are always identical. It is the 3rd nucleotide that can change. This is where the wobble comes in.

PCR stands for Polymerase Chain Reaction or gene amplification is the method of making multiple copies of the gene of interest using oligonucleotides and DNA polymerase.

Different steps of PCR are as follows:

(i) Denaturation : The target DNA is heated to a high temperature of 94° — 96°C. This results in the separation of two strands. Each strand serves as a template for DNA synthesis.

(ii) Annealing: The two oligonucleotide primers are hybridized or annealed to each single-stranded DNA following rule of complementarity. It is caused at low temperature of 40° – 60°C.

(iii) Extension (Polymerisation) : With the help of Tag DNA polymerase, the DNA is synthesized the primers using dNTPs and magnesium ions. The temperature is 72°C.

(iv) The newly synthesized DNA is subjected to same procedure to double the DNA content from the previous cycle.

Advantages of Road Transport over Air Transport: 

1. Door to Door Service: Road transport provides complete service by loading the goods at Consignor’s place and unloading them at the consignee’s place. There is also no need to wait for fall load shipment. 

2. Feeder Service: Motor vehicles carry goods to terminal points e.g., air ports, railway^tation, sea ports. They are also used for carrying goods to outlying villages which are not connected by airways or railways.

(a) Two features of a Bearer cheque: 

1. It contains the words ‘or bearer’ along with the name of the payee. 

2. The ownership of this cheque can be transferred by mere delivery. 

(b) Capital expenditure means the expenditure the benefit of which is not exhausted within the current year but is enjoyed over a long time period. Such expenditure is of non-recurring nature and results in acquisition of permanent assets. Property acquired with the help of capital expenditure is utilised by the business for a long time and thereby it earns revenue. Thus, all expenditure incurred to acquire or increase the value of fixed assets which are used in the business for the purpose of earning revenue are called capital expenditure. 

(c) Two features of a Non-trading organisation are: 

1. Non trading organisations are established and operated only for the purpose of rendering services to the members and the society and not for earning profits.

2. Non trading organisation prepare: 

(a) Receipt and Payment account. 

(b) Income and Expenditure account. 

(c) Balance Sheet. 

(d) Two methods or techniques of Sales Promotion are: 

1. Dealers sales promotion techniques, eg., free displays and trials, special gifts, display coupons etc. 

2. Customers sales promotion techniques, e.g., free samples, coupons, premium, fair and exhibitions etc. 

(e) The two advantages of a campus interview as a source of recruitment are as follows: 

1. Campus recruitment is very convenient and inexpensive because employer gets help from the placement cell of the educational institute in recruitment and selection. 

2. Well educated persons become available very quickly without any advertisement.

(i) The basic belief held by molecular geneticists that the flow of genetic information is unidirectional and occurs from DNA → RNA → Protein. 

(ii) Cryopreservation is a technique in which organisms, tissue and cells are preserved and stored at very low temperature of liquid nitrogen (-196°C) for years. They remain viable in frozen state for future use. 

(iii) Symbiosis is a beneficial association between members of different species in which both the partners are benefitted. 

(iv) Perianth is the term used when the calyx and corolla of the flower are indistinct.

(i) Walked semi-erect on kunckles. 

(ii) Snout was slightly projecting. 

(iii) Brow ridges were absent. 

(iv) Forelimbs and hindlimbs were of the same size. 

Chemogeny or chemical evolution in which the elements in the early atmosphere combined to produce simple and compound molecules, ultimately leading to the formation of complex organic molecules.

Genetic engineering approval committee’s function is to examine the validity of GM research and to inspect safety in use of GMO’s for the public.

(i) The Hardy-Weinberg principles states that allele and genotype frequencies in a population will remain constant from generation to generation in the absence of other evolutionary influences. 

(ii) It states that ontogeny recapitulates phytogeny. It means that embryos, in their development repeat the evolutionary history of their ancestors in a short, abbreviated form.

Integrated Pest Management or IPM is a systematic plan to manage crops using different pest control tactics to keep pests below the levels where they can cause economic damage, with least risk to environment. Management does not mean eradicating pests. It means finding tactics that are effective and economical and that keep environmental damage to a minimum.

There is a key belief that the more variety a landscape has, the more sustainable it is. The organic farmer wants to create a system where the insects that are sometimes called “pests” are not eradiated but instead are kept at manageable level by a complex system of checks and balance within a living and vibrant ecosystem. The eradication of pests is not only possible but also undesirable keeping in view the survival of predatory and parasitic interests. Thus, the use of biocontrol measures will greatly reduce our dependence upon toxic chemicals and pesticides.

The four main groups of pests are weeds; invertebrates (insects, mites, ticks, spiders etc); disease agents or pathogens (bacteria, fungi, viruses, nematodes etc); and vertebrates (birds, reptiles, rodents).

Biocontrol agents and bioherbicides are the two major approaches under IPM. Biocontrol is defined as controlling plant diseases and pests using biological methods. The biocontrol depends upon natural predation, e.g., ladybirds and Dragonflies are used to get rid of aphid and mosquitoes. Spores of Bacillus thuringiensis are used to control butterfly caterpillars. The fungus Trichoderma species are effective in control several plant pathogens.

Nucleopolyhedro viruses are pathogens that attack insects and other arthropods. Bioherbicides are the organisms and their extracts which destroy weeds without harming crop plants. They are of three types-predator herbivore (cochineal insect, a herbivore on Opuntia weed), smoother crops (Soyabeans, barley etc.) and mycoherbicides (Phytophthora palmivora does not allow Milk weed vine to grow in citrus orchards).

Immunoglobulin E

BOD: (Biological Oxygen Demand) It is the amount of dissolved oxygen needed by aerobic organisms to breakdown organic material present in a given water sample.

Its significance in an aquatic ecosystem is that it indicates water pollution.

Four effects of global warming: 

– Mean temperature of earth increases 

– Melting of ice caps and rise in sea level 

– Coastal floods 

– Extinction of large number of plant and animal species

or

Four measures to control noise pollution:

– Use of better designed, quieter machine industries. 

– Noisy industries should be away from residential areas. 

– Enforce restriction on the use of loudspeakers and amplifiers. 

– Plantation of trees on highways.

(i) Genetic erosion is the loss of genes from gene pool due to deforestation, urban expansion, damage to ecosystem, etc. 

(ii) Bio insecticides are living organisms like other insects, bacteria etc., which themselves or their products are used to control insect pests. 

(iii) Antigen is a substance which when introduced into a vertebrate body, provokes an immune response leading to acquired immunity. 

(iv) Psychosis is a kind of mental illness in which the person has no idea about his condition, loses contact with reality and cannot function in society.

G-6PD is an enzyme glucose 6 phosphate dehydrogenase which decomposes H₂C₂ formed during metabolism. The deficiency of this enzyme is an inborn error of metabolism controlled by specific gene. When persons suffering from malaria are given Primaquine it causes haemolysis because H₂O₂ produced during metabolism is not decomposed due to the deficiency of G-6PD enzymes. This H₂O₂ haemolysis the blood. The haemoglobin of haemolysed blood collects on cell membrane and RBC’s are deformed. In such distorted RBC’s, malarial parasite fails to survive and multiply. It means persons suffering from G-6PD deficiency are resistant to malaria. Such persons are, therefore, favoured by natural selection in area infested with malarial parasite. For this reason, G-6PD deficiency is found in 50% Negroes living in areas with malarial infection in African countries.

Seminiferous tubule : Formation of sperms

Chordae tendinae : Keeps the valves in position and prevents the back flow of blood in the atria.

(i) A- Ovum      B- Sperm

(ii) A is produced in ovary, B is produced in testes

(iii) Oviduct

(iv) (1) Progesterone and Oestrogen 

(2) Testosterone

(v) Serninal vesieles.

They produce a secretion which activates the sperms and provides a medium for their transportation.

(i) It is the ability of the body to focus clearly on objects, both close and distant from the eye. 

(ii) (1) More convex or almost round (2) Less convex or almost flat

(iii) Ciliary muscles and suspensory ligaments.

(iv) (1) Rods, rhodopsin (2) Cones, iodopsin