Carbon Compounds in
Cells

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Organic compounds consists of carbon and one or more additional elements covalently bonded to one another

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Those molecules that make up living things

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Carbon has the ability to covalently bond to at as many of four other atoms.
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Carbon has the ability to rotate freely around a single covalent bond
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As a result carbon has the ability to form many varied structures

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Organic compounds that contain carbon and hydrogen

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Atoms or groups of atoms that are attached to carbon backbones, that convey distinct properties, such as solubility and chemical reactivity.

3 Types of functional groups
1. Hydroxyl group - OH
2. Carboxyl group - COOH
3. Amines - NH
2

How Cells Use Organic
Compounds
1.
Biosynthesis Reactions - two molecules are joined together to form a larger molecule.
2.
Hydrolysis - a molecule is broken down into two smaller molecules as a result of the addition of water
3.
Enzymes - a special class of proteins that speed and initiate all chemical reactions in cells

1.
2.
3.
4.
5.
6.
Important Biological
Compounds
Carbohydrates
Lipids
Proteins
Nucleic Acids
Vitamins
Minerals

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Composed of carbon, hydrogen, and oxygen
• Functional groups present include Hydroxyl groups
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See pg. 53

Function of Carbohydrates in
Cells
1. The breakdown of carbohydrates in our cells are the major source of energy for the cell.
This energy can then be used by the cell for a variety of different processes
2. Major structural component of plant cells

Classification of Carbohydrates
•
Carbohydrates are classified according to the number of sugar molecules that make them up

3 Types of Carbohydrates
1. Monosaccharides
2. Disaccharides
3. Polysaccharides

• Carbohydrates`that consist of only a single sugar unit
• include glucose, fructose, galactose (pg 53)
•
These monosaccharides serve as the building blocks for much larger carbohydrates.
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Glucose is the major source of cellular energy in cells

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Composed of 2 monosaccharides
• cells can make disaccharides by joining two monosaccharides by biosynthesis.
•
Ex. Glucose + fructose = sucrose
Glucose + galactose = lactose
See page 54

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Composed of 3 or more monosaccharides
• made by way of biosynthesis of cells

1.
Starch
composed of hundred of thousands of glucose molecules
- made by plants to store energy for future use
- easily hydrolized into individual glucose

2.
Cellulose - form cell walls in plant cells
- also called fiber or ruffage
- indigestible by humans

3.
Glycogen - made in animal cells
- made for the purpose of short term energy storage
- stored in liver and muscles

4.
Chitin - a specialized polysaccharide that has nitrogen attached to it
- forms exoskeleton of arthropods

•
Lipids are nonpolar and do not dissolve in water
• composed of carbon, hydrogen, and oxygen
• contain the carboxyl functional group

1. Storage of energy in animals
• animal cells will convert excess carbohydrates into lipids to be stored for later use
2. Key component in cell membranes

3. Cushion for delicate organs
4. Carriers for vitamins A, D, E, K
5. Serve as the raw materials for the production of hormones
6. Insulation against the cold

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Fatty acids are key components of many lipids
• unsaturated fatty acids are liquid at room temperature composed of double bonds
• saturated fatty acids are solid at room temperature and contain only single bonds

1. Triglycerides
• formed by the union of 3 fatty acids and an alcohol called glycerol
• those composed of saturated fatty acids are called fats and are made in plants
• those that are composed of unsaturated fatty acids are called oils and are found in oils
• excess carbohydrates in the body are converted to triglycerides until the energy is needed.

2. Phospholipids
• composed of glycerol and fatty acids as well as phosphate groups
• are a major component of cell membranes

3. Waxes
• composed of very long chains of fatty acids
• serve as waterproof coating for plant leaves, animal fur, and feathers

4. Sterols
• serve as building blocks for hormones

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Composed of carbon, hydrogen, oxygen, and nitrogen
• contain the carboxyl group and the amine group

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Serve as the raw materials for the building of new cells and tissues
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Help in disease fighting
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Serve as transport agents in the body
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Help to speed and initiate chemical reactions (enzymes)

Key Components of Proteins
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Proteins are composed of smaller units called amino acids
• there are 20 different types of amino acids
• the average protein is about 200 A.A. long
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A.A acids can combine in millions of different ways to form millions of proteins

Protein Shape and Function
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Every protein made by the cell has its own distinctive shape
• it is the shape of the protein that helps to determine its function

Enzymes - Special Proteins
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All reactions that take place in our cells are initiated and sped up as a result of a
SPECIFIC enzyme.
•
All reactions require enzymes or they will not occur or occur much to slowly
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Enzymes are catalysts (see glossary)

Enzyme’s effects on Activation Energy

•
High temperatures or changes in pH can cause an enzyme to lose its normal 3-D shape ( denaturation )
• this denaturation causes the enzyme to lose its normal functioning

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Composed of building blocks called nucleotides
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2 main types
– deoxyribonucleic acid (D.N.A)
– ribonucleic acid ( R.N.A)

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See pg. 642

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See page 642