Carbohydratesassignment PDF

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Sabrina Costa

CHEM 1022

Carbohydrates

1. Which elements do carbohydrates contain, and in what ratio? Carbs contain carbon, hydrogen, and oxygen. They have a 1:2:1 ratio 2. If a sugar compound has 11 oxygen atoms, how many hydrogen atoms does it contain? It has 22 hydrogen atoms.

3. Based on their molecular formulas, which of the following are NOT carbohydrates? a. C3H803

c. C18H32O16

e. C16H32O2

b. C10H18O9

d. C4H8O2

f. C6H12O6

4. For each molecule below, determine if it is a monosaccharide, a disaccharide, or a polysaccharide: a. Fructose – mono

d. Glucose -

g. Chitin -poly

mono h. Starch -poly

b. Ribose - mono

e. Sucrose - disa i. Maltose- disa

c. Cellulose – poly

f. Glycogen poly

5. Describe a biological function for each of the following carbohydrates a. Cellulose connecting cells to form tissues signaling cells to grow and divide controlling the shape of plant cells allowing cells to withstand the turgor pressure of the fluids inside them

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b. Ribose – synethis of nucleic acids (RNA)

c. Starch – changes glucose to be used as energy for the body

d. Glycogen – a source of glucose for tissues throughout the body when blood glucose levels decline.

e. Deoxyribose – helps form the phosphate backbone of DNA molecules

f. Fructose – source of energy for the cells

g. Sucrose – provides energy required to form physical and mental functions

6. Complete these word equations a. Glucose + glucose  maltose b. Glucose + fructose  sucrose c. Monosaccharide + monosaccharide  disaccharide d. Lactose + water  fructose e. Disaccharide + water  Videos for dehydration synthesis and hydrolysis http://www.youtube.com/watch?v=b7TdWLNhMtM&feature=related http://www.youtube.com/watch?v=UyDnnD3fMaU

7. Briefly describe the process of the hydrolysis reaction for carbohydrates. - When a carbohydrate is broken into its component sugar molecules by hydrolysis, is called saccharification. Hydrolysis is the reverse of the

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condensation reaction where two molecules join into a larger one and make a water molecule.

8. Lastly, plants like grasses are almost completely cellulose with very little starch or monosaccharides. That being said WE (animals) cannot get any energy gains from eating cellulose as we lack the necessary enzyme which allows us to hydrolyze the bonds in cellulose turning it into glucose. BUT, don’t cows eat grass????? Well yes they do, but they do not exactly digest (hydrolyze) the cellulose by themselves. Watch this video from University of Wyoming to learn how they can digest cellulose. http://www.youtube.com/watch?v=SM6IvygITCE Even though cows eat grass, they can't digest it on their own. This is because cows can't make the enzymes needed to break down some parts of plant cells. For example, cows can't digest cellulose. To do this, they need an enzyme called cellulase.

9. Draw the cyclic and open-chain structures of the monosaccharide glucose.

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10. Explain how the monosaccharides glucose and galactose differ. Discuss why they would not react the same way in nature. Galactose has a higher melting point than glucose as a result of the structural differences. 11Describe the structure and composition of the following types of carbohydrates by completing this table. Exa Carboh mpl ydrate e

Structure and composition

starch

(C6H10O5)n

bre ad

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cellulos e

ste ms of plan ts

glycoge n

stor â BG  glycogen breakdown  á age BG for m of gluc ose in ani mal s in liver and mus cles

glucose

fruit (C6H12O6) s

Multiple choice questions 1) Collagen is: a) A flexible fat molecule found in skin b) A polysaccharide with high elasticity c) A glycoprotein d) A globular protein e) A heme protein 2) Specific dynamic action is the energy needed to: a) carry out a specific set of moving exercises b) exist for 24 hours under normal conditions with no exercise c) digest and metabolize food d) convert one kilogram of adipose tissue into energy e) maintain life for one hour with neither exercise nor food

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3) In the Energy Equation, exercise represents: a) all energy expenditure except that lost through basal metabolism b) energy expended in sports c) energy expended in activities designed to maintain good health d) the composite of all energy expended through physical work of any kind e) all energy expenditure beyond the level of 1 Cal per minute 4) An aromatic compound is one that a) Has a pleasant odour b) Burns cleanly c) Contains a cyclohexane ring d) Contains at least one benzene ring e) Contains only Carbon and hydrogen 5) Of a) b) c) d) e)

the following, the food that has a nutritive value of about 9 Cal/g is: corn oil table sugar protein lactose starch

6) A can of chicken soup with noodles provides 10 g of protein, 14 g of carbohydrate, and 5 g of fat. The total number of Calories provided by one can of soup is: a) 157 b) 197 c) 165 d) 232 e) 141 7) Fats and oils are differentiated from each other on the basis of their: a) melting points b) densities c) optical activities d) glycerol content e) boiling points 8) Triglycerides are used in the manufacture of: a) soap b) vitamins c) synthetic detergents d) high-octane gasoline e) enzymes 9) The polymerase chain reaction (PCR) is important because a) One can produce large amounts of RNA b) One can produce large amounts of proteins c) One can produce large amounts of DNA

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d) Any polymer can be formed in large quantities using it e) Totally synthetic DNA can be produced 10) a) b) c) d) e)

On the molecular level, fats are more likely than oils to have: much unsaturation and short side-chains little unsaturation and short side-chains much unsaturation and long side-chains little unsaturation and long side chains neither unsaturation nor side-chains

11) Vegetable oils and fish oils differ from animal fats primarily in that the vegetable and fish oils contain: a) carbon-carbon double bonds b) oxygen atoms c) glycerol units d) nitrogen atoms e) peptide bonds 12) a) b) c) d) e)

Cholesterol is a: fully saturated triglyceride highly unsaturated triglyceride fatty acid steroidal alcohol drying oil

13) a) b) c) d) e)

Cholesterol does not occur in: butter beef fat lard coconut oil human fat

14) a) b) c) d) e)

The animal body stores its excess energy largely as: carbohydrates cellobiose glyceryl triesters proteins polysaccharides

15) a) b) c) d) e)

The most highly studied food additive in history is Sucralose Saccharin dextrose Aspartame fructose

16)

The name carbohydrate reflects:

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a) b) c) d) e)

the ratio of carbon to hydrogen in the molecule the ratio of carbonyl groups to total carbon content the combined rations of carbon, hydrogen and oxygen the ratio of carbon to oxygen the ratio of hydrogen to oxygen

17) a) b) c) d) e)

A substance is optically active if it: produces polarized light absorbs polarized light rotates the plane of polarize light converts polarized light into unpolarized light converts unpolarized light into polarized light

18) a) b) c) d) e)

Fish cooks at a lower temperature than meat primarily because Fish have no muscle Fish muscle has shorter fibres Amines in fish act as marinades Fish is less dense than meat Fish contains more omega-3 fatty acids

19) a) b) c) d) e)

Invert sugar is another name for: glucose fructose galactose maltose a mixture of equal amounts of glucose and fructose

20) Potato starch is a nutrient while lettuce is a low-calorie roughage because: a) humans lack cellobiase b) starch is composed largely of glucose units while lettuce is composed largely of galactose units c) the monosaccharide units of starch are joined to each other through glycosidic links while those of lettuce are joined through ester links d) humans cannot digest and metabolize galactose e) potatoes are generally cooked while lettuce is eaten raw 21) a) b) c) d) e)

The carmelization process involves: Melting of butter and sugar Melting of brown sugar Reaction between proteins and sugars Reaction between fat and sugar Thermal decomposition of sucrose

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22) a) b) c) d) e)

The component common to all dietary roughage and fiber is: complete protein essential amino acids nonessential amino acids polyunsaturated triglycerides indigestible carbohydrate...