Carbohydrate and its test - class-X

Glucose is a monosaccharide, not a polysaccharide. Therefore, the pair 'Glucose; polysaccharide' is incorrect.

Carbohydrates are the most abundant biomolecules found on the face of the earth. This is so because every year plants and algae through the process of photosynthesis convert more than 100 billion metric tons of carbon dioxide and water to cellulose and other products for use by the plants. Some bacteria undergo photosynthesis but it is anoxygenic as bacteria has only pigment system I. Thus, the correct answer is option A.

Carbohydrates (CHO) - These are the principle energy storage molecules. They contain carbon (C), hydrogen (H), and oxygen (0) in a 1:2:1 ratio and are classified according to their size into monosaccharide, disaccharide, polysaccharide.

Monosaccharides are simple sugar having single chain or single ring structure which contains 3-7 carbon atoms. Example is glucose with 6 carbons, 12 hydrogens, and 6 oxygens.

Disaccharides: Double sugars are formed by dehydration reaction between 2 monosaccharides glucose + glucose ------ - > maltose + water. Disaccharides are too large to pass through cell membranes and must be digested to simple sugar units by hydrolysis (add water).

Polysaccharides are long chains of simple sugar molecules. The two major molecules of importance are starch, which is used for storage form for carbohydrate fuel in plants and glycogen, which is used for storage form for carbohydrate fuel in animals.

Function: It is ready source of cellular fuel & cellulose, is used for structural support in plants and carbohydrates help form cell receptors for recognition. Hence, option C is correct.

Carbohydrates are made up of C: H: O, having H and O in the ratio of 2:1 and the general formula is (CH2O)n. Sources of carbohydrates in our food are cereals and pulses. The caloric value is 4.1 kcal/g.

Most common monomer used in polysaccharides is glucose. For example, starch, cellulose, glycogen all are polymers derived from glucose. Plants synthesize carbohydrates as glucose or fructose and store in other form like starch. The type of linkage between glucose molecules is different in storage and structural polysaccharides. The linkage in storage polysaccharides is $\alpha$- whereas $\beta$-linkage is present between glucose molecules in structural polysaccharides.

Plant cell is characterised by presence of a cellulosic cell wall which is dead at maturity. The cellulose is a structural polysaccharide made up of glucose molecules linked by $\beta$-glycosidic linkage.

Hydrolases catalyse hydrolytic reactions. Some of the important hydrolases includes amylases, sucrase, lactase, maltase, protease, esterase etc. 

C_nH_2nO_n is a general formula of monosaccharides. Monosaccharides are the simplest carbohydrates which cannot be hydrolyzed into smaller units. They usually have 3-7 carbon atoms per molecule. They are the compounds of carbon, hydrogen, and oxygen in which hydrogen and oxygen occur in the ratio of 2:1 as in a molecule of water. Thus, they are also known as hydrates of carbon. 

Disaccharides are oligosaccharides which are formed by condensation of two monosaccharides. Lactose is a disaccharide. It is made up of two hexose molecules, glucose, and galactose. Lactose is also known as milk sugar because it is found in milk. It is a reducing sugar. Thus, the correct answer is B

Carbohydrates which cannot be hydrolyzed further into smaller components are called monosaccharides or simple sugar. Ribose is a sugar which cannot be hydrolyzed further as it is a smaller sugar with 5 carbon. Maltose, Sucrose, and Lactose are complex sugar which can be hydrolyzed into a smaller unit of sugars. Thus, the correct option is A.

Insulin is a peptide hormone which helps to maintain the blood sugar level. it is secreted by the beta cells of pancreas.

The complex carbohydrates which are formed by polymerization of a large number of monosaccharides(more than 9 ). They are also known as glycans. Sucrose, Lactose, and maltose are disaccharides. Glucose and fructose are monosaccharides. Glycogen, cellulose, and starch are polysaccharides. Thus, the correct answer is D.

Chitin is the most abundant organic substance. It is a complex carbohydrate which is found in fungal walls as a structural component. It is also called as fungal cellulose. It provides strength and elasticity. Thus, the correct answer is B.

Cellulose, Fructose, and maltose are carbohydrates but pepsin is an enzyme made of protein.

Cutin is a polymer of glycerol and certain types of fatty acids. It is an integral part of the cuticle of the leaf. 

Inulin is a storage polysaccharide in roots of Dahlia and related plants. It is also known as a fructan. It is not metabolized in the human body and is readily filtered through the kidney. Therefore, it is used in testing kidney function. Thus, the correct answer is B.

Macro-molecule chitin is a complex nitrogen-containing polysaccharide containing amino sugars and chemically modified sugar for example -glucosamine, N-acetyl-galactosamine etc.

Green plants produce carbohydrates by the process of photosynthesis by using water, carbon die oxide and solar energy. Apart from this, some bacteria and algae can also produce carbohydrates in the form of food. 

Chitin is the substance which is fibrous and made up of the long-chain polymer of N-acetylglucosamine, is a derivative of glucose. It is a major constituent of the exoskeleton of arthropods, crabs and also make the cell wall of fungi.

• Primary metabolites are those that are formed during the growth phase and supports in the overall development of cells. E.g., Carbohydrates, vitamins, proteins etc.
  
• Secondary metabolites are those which are the end products of primary metabolites and are required for ecological activities of cells. E.g., Carotenoids, morphine etc. 

Starch is a type of polysaccharide which is present in rice. Glycogen is stored polysaccharide in animal tissues.

The glycosidic bond is a bond that holds a carbohydrate molecule with another group, which may or may not be a carbohydrate. Polysaccharides contain several monosaccharides that are linked to one another by glycosidic bonds. In water each water molecule binds four other water molecules by hydrogen bonds. This helps the water molecules to hold together (cohesion of water). 

Chitin carbohydrates are the oldest in the given as it is a carbon-based factor. protein, lipids consist chain of nitrogen, hydrogen and carbon atoms however carbohydrate consists of a longer chain of carbon as well as various other groups of compounds. so, the correct option is 'chitin carbohydrates'.

The pentose sugar present in guanosine is ribose  The base attaches to the carbon no.1 and the phosphate bonds to carbon no. 5.

• A disaccharide is made up of two monomers.
• Maltose is made up of two molecules of Glucose by O-glycosidic linkage.
• So, the correct option is 'Maltose'.

Carbohydrates are polyhydroxy aldehydes and ketones. They have two functional groups alcohol and either aldehyde or ketone. Most common carbohydrates are compounds of carbon, hydrogen and oxygen where hydrogen and oxygen occur in the ration of 2:1 like water. Hence, carbohydrates are also called as hydrates of carbon. Carbohydrates have asymmetric carbon atoms, hence, carbohydrates are optically active and rotate the plane of polarised light .

Cellulose is the most abundant organic polymer on earth. Cellulose is an important structural component of the primary cell wall of green plants. Glucose is one of the primary molecules, which serve as energy sources for plants and animals. It is the most important simple sugar in human metabolism. Cellulose can be broken down chemically into its glucose units by treating it with concentrated acids at high temperature.

Simple carbohydrates are generally soluble sugars. Simpler carbohydrates are of two types Monosaccharides and Oligosaccharides. Monosaccharides are monomer sugars which cannot be hydrolysed further into smaller units, e.g., trioses, tetroses, pentoses, hexoses and heptoses. Oligosaccharides are made up of a few units of monosaccharides.

The substance which is synthesized in golgi body is polysaccharides. Golgi is a part of the cellular endomembrane system, the Golgi apparatus packages proteins into membrane-bound vesicles inside the cell before the vesicles are sent to their destination. The Golgi apparatus resides at the intersection of the secretory, lysosomal, and endocytic pathways. It is of particular importance in processing proteins for secretion, containing a set of glycosylation enzymes that attach various sugar monomers to proteins as the proteins move through the apparatus.

In the primary plant cell wall, the major carbohydrates are cellulose, hemicellulose and pectin. The cellulose microfibrils are linked via hemicellulosic tethers to form the cellulose-hemicellulose network, which is embedded in the pectin matrix. The most common hemicellulose in the primary cell wall is xyloglucan.

The bonds present between two carbohydrate molecules is glycosidic. A glycosidic bond is a type of covalent bond that joins a carbohydrate molecule to another group, which may or may not be another carbohydrate. A glycosidic bond is formed between the hemiacetal or hemiketal group of a saccharide and the hydroxyl group of some compound such as an alcohol. A substance containing a glycosidic bond is a glycoside.

Sweet tasting carbohydrates are called sugars, e.g., glucose and fructose. Starch is a storage polymer of glucose and is tasteless till it is broken down into monomer glucose molecule. Lactose is milk sugar. Proteins are polymers of amino acids which are tasteless except for some like aspartic acid. Saccharine is an artificial sweetener. Saccharin is more sweet than common table sugar or sucrose but has a bitter after taste.

Glucose is a monosaccharide carbohydrate. Glycogen is an important storage polysaccharide in animals like starch in plants. Glycogen and starch are homopolysaccharides made up of glucose units only. Glycogen is stored in liver and muscles in animals including humans. Starch is usually stored in endosperm and cotyledons of seeds. Waxes are a type of lipids.

Carbohydrates are the most abundant bimolecules found on the face of the earth. This is so because every year plants and alga through the process of photosynthesis converts more than 100 billion metric tones of $CO _2$ and $H _2O$ to cellulose and other products for use by the plants.

Proteins are the body building nutrients. Cell is the building block of our body. Most of the structures of the cells are formed with protein. Without protein no cell can be formed and be functional. So, proteins are called the body building nutrients.

Excess glucose is stored as starch or glycogen. Starch is storage polysaccharide in plants. Glycogen is storage polysaccharide in animals. In animals, including humans, glycogen is stored in two locations: muscles and liver.

Carbohydrates which are present in the cell membrane take part in cell recognition. Cell recognition is defined as an active process giving rise to a specific response. 

Inulin is a group of naturally occurring polysaccharides produced by many types of plants, consisting of a chain of fructose units.

Carbohydrate is essential as the most immediate and efficient fuel to the muscles. In its circulating form in the blood, carbohydrate is called as glucose, and its storage form in muscles and in the liver is called as glycogen. When the athlete first begins to exercise, body draws on the circulating glucose as its first source of energy. Glycogen, as the storage carbohydrate, comes in when circulating glucose drops to a lower level.  Without enough carbohydrates, performance as an athlete will be seriously impacted. 

Answer is option A i.e. "Starch, Glycogen, Cellulose"
Poysaccharides are carbohydrate polymers (e.g. starch, cellulose, or glycogen) which are made up of more than 10 sub-units of monosaccharide molecules join together.
Starch, glycogen and cellulose are polysaccharides of glucose. Maltose, sucrose and lactose are disaccharides, while, fructose and galactose are monosaccharides.

Carbohydrates, proteins and fats in the foods provide energy for the body functions and physical activities. They, however, do not produce same amount of energy. the following is the energy-contribution by respective molecules.
Carbohydrates- 55-75% of energy contribution
Proteins- 10-15% of energy contribution
Fats- 15-30% of energy contribution
Therefore, the correct answer is option D.

Chitin is a carbohydrate. It is a long-chain polymer of a N-acetylglucosamine, a derivative of glucose, and is found in many places throughout the natural world. It is a characteristic component of the cell walls of fungi, the exoskeletons of arthropods such as crustaceans (e.g., crabs, lobsters and shrimps) and insects, the radulae of molluscs and the beaks and internal shells of cephalopods, including squid and octopuses. The structure of chitin is comparable to the polysaccharide cellulose, forming crystalline nanofibrils or whiskers. 

The chickpea or chick pea is a legume of the family Fabaceae, subfamily Faboideae. It is also known as gram, or Bengal gram, garbanzo or garbanzo bean, and sometimes known as Egyptian pea, ceci, cece or chana, or Kabuli chana. It is the major source of proteins and not of carbohydrates. Wheat, rice and sorghum are the sources of carbohydrates. Thus, the correct answer is option B.

Human food should consist of a variety of nutrients such as carbohydrates, minerals, fats, proteins, vitamins and fibre. However, carbohydrates provides the human body with maximum energy. Carbohydrates are broken down to various forms of glucose which acts as the best source of energy. A diet rich in carbohydrates includes potatoes, both white and sweet and rice (mainly brown rice) and foods made from whole wheat.

The composition of a healthy human food includes carbohydrates, vitamins, proteins, fats, minerals and fibre. While the consumption of these nutrients are required in varied quantities, usually depicted in a triangle with carbohydrates forming the base. Of all the nutrients, carbohydrates produce the maximum energy required for the body which is followed by fats. Proteins produce energy only under emergency situations.

About 70% of our energy requirements should be met by carbohydrates.

Carbohydrates, proteins and fats in the foods provide energy for the
body functions and physical activities. They, however, do not have
same energy content. The following is the energy-content by
respective nutrients:
1 gram of carbohydrates- 4 kcal
1 gram of protein- 4 kcal
1 gram of fats- 9 kcal
Therefore, the correct answer is option B.

Carbohydrates are molecular compounds made from just three elements carbon, hydrogen and oxygen. Carbohydrates are one of the main types of nutrients. They are the most important source of energy for your body. Your digestive system changes carbohydrates into glucose (blood sugar). Your body uses this sugar for energy for your cells, tissues and organs. 

In animals fats, carbohydrates and proteins are responsible for generation of energy.
Proteins are metabolized by breaking down into individual amino acids by various enzymes and hydrochloric acid present in the gastro-intestinal tract which are further broken down to α-keto acids which can be recycled in the body for generation of energy, and production of glucose or fat or other amino acids.
Fats are the major contributor of the molicules like acetyl-CoA which is an integral part of Krebs cycle and generates energy.
Carbohydrates takes part in cellular process like glycolysis and leads to generation of energy.
Vitamins are not directly involved in generation of energy although they indirectly support the process of energy production.
So, the correct answer is option C.

Oligosaccharides are formed by joining together 2-9 monosaccharides molecules. For example maltose, sucrose, lactose.

All monosaccharides with six carbon atoms, resembling glucose, fructose, etc have an empirical formula of C$ _n$H$ _{2n}$O$ _n$. However, the molecular formula of Rhamnose is C$ _6$H$ _{12}$O$ _5$.

Glucose is a hexose sugar made up of six carbon atoms. Its general formula is $\displaystyle Cn{ H } _{ 2 }nOn$. It is utilized for energy production.

Cellulose is the most abundant carbohydrate, in fact, the most abundant organic compound in nature. It is the main structural polysaccharide of the plants. Thus option B is the correct answer.

Chitin is a structural polysaccharide that is insoluble in water, resistant to many chemicals, and insoluble in most organic solvents, making all the provided options correct.

When injecting substances into the blood, they must be isotonic to prevent damage to red blood cells. Osmotic potential is the property that determines the tonicity of the solution.

• Low-calorie sweeteners used by the people of West Africa are brazzein, thaumatin, monellin, pentadin, miraculi etc. 
• Brazzein is a stable proteinaceous substance made up of 54 amino acids. It is extracted from the fruit of Pentadiplandra brazzeana Baillon. 
• It is found 2000 times sweeter than sucrose.
  Therefore, the correct option is A.

Pectin is mostly present in the cell wall of the plant and the concentration in the skin of fruits. It consists of esterified D-galacturonic acid resides in an alpha-(1-4) chain. It is a secretory product which leaves the cytoplasm and deposits on the cell wall of the plant. It combines with cellulose and lignin to provide structural support to the plant.

Hyaluronic acid (HA) is a mucopolysaccharide. It is made up of glucuronic acid and acetylglucosamine. It found in the extracellular fluid of animal tissues, the vitreous humor of the eye, cerebrospinal fluid etc. The biological functions of HA include maintenance of the elastoviscosity of liquid connective tissues such as joint synovial and eye vitreous fluid. Its function in the body is, amongst other things, to bind water and to lubricate movable parts of the body, such as joints and muscles. It also occurs in cementing material between animal cells as well as inside cell coat. Thus, the correct option is B.

Glycogen is an animal starch. It is a polysaccharide food reserve in animal, bacteria, and fungi. It is stored mainly in liver and muscles. The granules of glycogen are ellipsoid flattened structures that lie freely inside the cell. Thus, the correct answer is option D.

The bond between two phosphate groups is a phosphoanhydride bond which is considered as high energy bond. ATP has two high energy phosphoanhydride bond. ADP has one phosphoanhydride bond. Creatine phosphate also has high phospahte bond between the nitrogen and phosphate. The phosphate bond in glucose phosphate is the weakest so it will yield less than 4kcal/mol of energy when phosphate bond is hydrolysed.

The gallbladder is a small storage organ located inferior and posterior to the liver. Though small in size, the gallbladder plays an important role in our digestion of food. The gallbladder holds bile produced in the liver until it is needed for digesting fatty foods in the duodenum of the small intestine.

Hyaluronic acid is a glycosaminoglycan composed of repeating disaccharide units of D-glucuronic acid and N-acetyl-D-glucosamine. The question might be referring to specific complex polysaccharides; however, agar-agar is also a complex mixture. Given the options, Hyaluronic acid is the standard answer in many textbooks for this context.

Glucose is the simplest 6 carbon molecule that is the most common monomer of carbohydrates. It is the most abundant monosaccharide with the molecular formula C$ _6$H$ _1$$ _2$O$ _6$. It is mostly made by plants and green algae during photosynthesis.

A non-reducing sugar is a carbohydrate that is not oxidized by a weak oxidizing agent (an oxidizing agent that oxidizes aldehydes but not alcohols, such as the Tollen's reagent) in basic aqueous solution. The characteristic property of non-reducing sugars is that, in basic aqueous medium, they do not generate any compounds containing an aldehyde group. Example : sucrose, which contains neither a hemiacetal group nor a hemiketal group and, therefore, is stable in water.

• Polysaccharides are carbohydrates whose molecules are made up of sugar molecules bonded together. They are composed of long-chain of monosaccharides. They range in structure from linear to highly branched form. They are made up of sugar mainly including glucose, fructose, etc.

Simple sugars are the monomers for the polysaccharides or carbohydrates. Simple sugars include glucose, fructose, ribose, xylose, etc.

Glycogen is a multibranched polysaccharide of glucose that serves as a form of energy storage in humans, animals, and fungi

Carbohydrates are also called saccharides because their basic components are sugars. Monosaccharides are those sugars or simple carbohydrate monomers which cannot be hydrolysed further into smaller components. They have a general formula of $C _nH _{2n}O _n$. Depending upon the number of carbon atoms, monosaccharides are of five types : trioses (having 3 carbon atoms, glyceraldehyde), tetroses (having four carbon atoms, e.g., erythrose), pentoses (having five carbon atoms, e.g, ribose), hexoses (having six carbon atoms, e.g.; glucose), heptoses (having seven carbon atoms, e.g., sedoheptulose).

Photosynthesis is a process of generating the food for green plants and other organisms. It involves the conversion of light energy, normally from the Sun, into chemical energy in form of ATP. This chemical energy is stored in carbohydrate molecules, such as sugars, which are synthesized from carbon dioxide and water. In most cases, oxygen is also released as a waste product. Most plants, most algae and cyanobacteria perform photosynthesis. Such organisms are called photoautotrophs. Thus, option A is correct. Carbohydrates are not produced by fungi and viruses. Thus, other options are wrong.

A primary metabolite is a type of metabolite, which is directly involved in the normal growth, development, reproduction of an organism. e.g. Cellulose, cholesterol, triglycerides. Secondary metabolites which are not directly involved in the growth, development.  Secondary metabolite performs another function like defence. e.g. lecithin present in WBC which help in the recognition of foreign pathogen.

Chitin is a long-chain polymer of N-acetylglucosamine, which is a derivative of glucose. It is classified as a polysaccharide.

Chhtitn is the main ingredient in the exoskeletons of arthropods and crustaceans and is also in the cell walls of fungi. That means everything from beetles, spiders, and butterflies to lobsters, crabs, and shrimps have some chitin in their protective armors.

Primary functions of carbohydrates in the cells are as follows as:

$686$ kcal energy is utilised in the synthesis of one gram mole of glucose. 

Raw banana has a bitter taste due to the presence of starch. When the banana ripens, the starch is converted to sugar in the form of glucose. The sugar is responsible for providing a sweet taste. So, the conversion is starch to sugar. 

Glucose and fructose are simple sugars known as monosaccharides. Sucrose is a disaccharide. Sucrose is made up of 2 simple sugars - glucose + fructose. 

Iodine solution is a standard chemical indicator used to test for the presence of starch, which is a type of carbohydrate. It turns blue-black in the presence of starch.

Iodine present in the aqueous Potassium iodide solution gets entangled in the starch and forms starch Iodide complex. Hence starch turns blue-black or purple-black in colour.

Boiling a leaf in alcohol removes chlorophyll, which otherwise masks the color change when testing for starch with iodine. Once the chlorophyll is dissolved, the leaf becomes white or pale, making the blue-black iodine color change clearly visible.

The Respiratory Quotient (R.Q.) is the ratio of CO2 produced to O2 consumed. For the complete oxidation of glucose (C6H12O6 + 6O2 -> 6CO2 + 6H2O), the ratio is 6/6, which equals 1.

Blood glucose levels are maintained by hormones, such as insulin and glucagon. A postprandial glucose test is a blood glucose test that determines the amount of glucose in the blood after a meal. Normally, blood glucose levels increase slightly after eating. This increase causes the pancreas to release insulin. A postprandial blood glucose test measures blood glucose exactly 2 hours after eating a meal. By this point, blood sugar has usually gone back down in healthy people, but it may still be elevated in people with diabetes.

A little glucose is added to a blue green chemical called as Fehling's solution in a test tube for test of glucose.

Fehling's test is given by glucose, which is a reducing sugar. It produces a red precipitate with Fehling's solution A and B, when heated.

During the complete breakdown of one glucose molecule via glycolysis, the link reaction, and the Krebs cycle, a total of 10 NADH molecules are produced (2 in glycolysis, 2 in the link reaction, and 6 in the Krebs cycle). In addition, 2 FADH2 molecules are also produced.

Fehlings can be used to screen for glucose in urine, thus detecting diabetes.