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The Chemistry of Biology-

Carbon Compounds

IV. Carbon Compounds

A. Organic Compounds 1. 2. Characteristics of carbon include: a) Carbon forms: b) Carbon can form bonds with other ______________________as well as a

variety of ______________________ such as _______________________ ________________________________________________________.

c) Carbon can form: Carbon can form ______________________.

B. Macromolecules

1. Many of the molecules in living cells are so ____________ that they are known as _________________________. This means “_______________________”.

2. Macromolecules are made from______________________________________. 3. The four groups of organic compounds found in living things are:

a) b) c) d)

Biological Molecules 1

Biological MoleculesWhat are the building blocks of life?

Why?From the smallest single-celled organism to the tallest tree, all life depends on the properties and reactions of four classes of organic (carbon-based) compounds—carbohydrates, lipids, proteins, and nucleic acids. These organic molecules are the building blocks of all living things, and are responsible for most of the structure and functions of the body, including energy storage, insulation, growth, repair, communica-tion, and transfer of hereditary information. Simple organic molecules can be joined together to form all the essential biological molecules needed for life.

Model 1 – Molecules of Life

Carbohydrates (monosaccharides)

Glucose Galactose Fructose

Lipids

Glycerol Fatty acids Triglyceride (fat or oil)

Proteins (amino acids)

Alanine Cysteine Amine group

Nucleic acids (nucleotides)

O

OH

HH

H

OH

OH

H OH

H

OH

O

OH

HH

OH

H

OH

H OH

H

OH

O

OH

H

OH

OH

H

H

OH OH

C

C

C

H

H

OH

H OH

H

H OH

C

O

(CH 2)12CH3OH

C

O

(CH 2)7CH=CH(CH 2)7CH3OH C

CH

H

H OC

O

CH3

OCO(CH 2)7CH=CH(CH 2)7CH3

CH

H OC

CH3

O

C

O

(CH 2)14CH3OH

C

R

H

N C

O

OH

H

HC

H

N C

O

OH

H

H

CH2SH

C

CH3

H

N C

O

OH

H

H

Proteins�(amino�acids)

Alanine Cysteine

Variable� Rside�chain

Carboxylicacid�group

Aminegroup

NO

O

OH

OH

OH

O

P N

NN

NH2

OH

Variable R side chain

Carboxylicacid group

Nitrogen base

Phosphate group

Sugar

2 POGIL™ Activities for High School Biology

1. Use Model 1 to show which atoms are present in each type of molecule by listing the symbol for each atom included. Carbohydrate has been done for you.

a. Carbohydrate— C, H, O c. Amino acid—

b. Lipid— d. Nucleic acid—

2. Which type of molecule includes an example with a long-chain carbon backbone?

3. In the molecule referred to in the previous question, what is the dominant element attached to the carbon backbone?

4. The fatty acid chain of the lipids is often referred to as a hydrocarbon chain. Discuss with your group why the chain is given this name and write a one-sentence defi nition for a hydrocarbon.

5. Which molecule has a central carbon atom with four different components around it?

6. Which molecule has a sugar, nitrogenous base, and phosphate group?

7. Discuss with your group members some similarities among all four types of molecules. List as many as you can.

8. What is the chemical formula of the fi rst carbohydrate molecule shown?

9. What three structural groups shown do all amino acids have in common?

10. There are 20 naturally-occurring amino acids, and each one only varies in the structure of the R side chain. Two amino acids are shown in Model 1. What are the R side chains in each?

Read This!During chemical reactions, the bonds in molecules are continually broken and reformed. To break a bond, energy must be absorbed. When bonds are formed, energy is released. If more energy is released than absorbed during a chemical change, the process can be used as a source of energy. A general rule for processes such as respiration is the more carbon atoms there are in a molecule, the more energy that molecule can provide to the organism when it is used as food.

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V. Carbohydrates

A. Characteristics of Carbohydrates 1. These compounds are made up of ____________________________________ in a ratio of

_______________. 2. Examples of carbohydrates are: 3. The carbohydrates are known as the “quick energy” foods because: 4. There are two main functions of carbohydrates:

a) b)

5. The smaller molecules that make up the carbohydrates are _______________________________. B. The Sugars

1. Carbohydrates are classified according to: 2. __________________________ contain only ______ molecule of sugar. 3. __________________________ are composed of ____ molecules of sugar bonded together. 4. __________________________ are composed of ________ molecules of sugar bonded together.

C. Three Common Polysaccharides

1. Starch a) Only found in ____________. b) This is the way that plants ______________________________________________ c) Many, many molecules of _____________ are bonded together to form ____________.

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2. Glycogen

a) Only found in _______________. b) This is the way that animals _________________________________. c) The liver bonds together many, many molecules of ____________ to form ______________.

3. Cellulose

a) Cellulose is the b) It gives __________ to the plant _______________. c) Cellulose is the major component of wood and paper.

VI. Lipids

A. Examples of lipids are ___________________________________. B. These compounds are generally not ______________ in water. C. These contain the elements ____________________________________ but not in the_________

ratio seen in the ___________________. D. There are two building blocks of lipids: ________________________________.

1. A lipid has: 2. Circle and label the glycerol molecule in each of the above drawings. 3. Label the three fatty acid tails in each drawing. 4. If a fatty acid tail has at least one ____________________________, it is said to be an

____________________ fat.

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5. If a fatty acid tail has no ________________________________, it is said to be a _______________________ fat.

6. Which of these drawings is a saturated fat? Which is an unsaturated fat? 7. Saturated fats tend to be __________ at room temperature. Examples are: 8. Unsaturated fats tend to be __________ at room temperature. Examples are: 9. Saturated fats clog up your arteries and veins. Please do not eat too many of these!!!!

E. Uses of Lipids

1. 2. 3. 4.

F. Biochemical Reactions

Duringa_________________________bondsinmoleculesarebrokenandreform.Breakingbondsrequires___________________________andformingbondsreleasesenergy.Inreactionsoccurringinorganismsifmoreenergyisreleasedthanrequiredtheprocessisusedasasourceof______________________energy.Incellreactionssuchasrespirationthemore___________________________atomsinamoleculethemoreenergythemoleculeprovidestotheorganism.

Isacarbohydrateoralipidmorelikelytobeagoodsourceofenergyforanorganism?Why?

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VII. Nucleic Acids

A. Nucleic acids are macromolecules containing the elements: B. There are two kinds of nucleic acids: ______________________. C. The building blocks of the nucleic acids are _____________________. D. Nucleic acids ______________________________________________.

VIII. Proteins

A. Proteins are macromolecules that contain: B. The building blocks of proteins are ________________. There are _______________________.

C. Each amino acid has four parts. Label these groups on the drawing above.

D. There are many, many uses for proteins

1. enzymes 2. hormones 3. transport proteins such as hemoglobin 4. contractile proteins such as in muscle tissue 5. antibodies 6. membrane proteins 7. structural proteins such as bones and muscles

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Chemistry of Life Review Question Answer