Chapter 3 Carbon Compounds in Cells

Organic Compounds Contain carbon and one or more additional elements Contain carbon and one or more additional elements ONLY living things can synthesize organic compounds ONLY living things can synthesize organic compounds

Carbon Bonding C, H, O & N are the most abundant elements in living things C, H, O & N are the most abundant elements in living things Most of the H & O are linked as water Most of the H & O are linked as water How many covalent bonds can carbon form? How many covalent bonds can carbon form? Helps form hydrocarbon backbone of organic molecules Helps form hydrocarbon backbone of organic molecules

Functional Groups Atoms or groups of atoms that are bonded to the carbon backbone Atoms or groups of atoms that are bonded to the carbon backbone Give distinct properties such as solubility and chemical reactivity to the entire molecule Give distinct properties such as solubility and chemical reactivity to the entire molecule CD ROM 1-2 CD ROM 1-2

Monomers Polymers Small molecules Small molecules Building blocks joined to make polymers Building blocks joined to make polymers Amino acids Amino acids Fatty acids Fatty acids Monosaccharides Monosaccharides Nucleotides Nucleotides Large molecules Large molecules Can be broken down to form monomers Can be broken down to form monomers Proteins Proteins Lipids Lipids Carbohydrate Carbohydrate Nucleic Acids Nucleic Acids

Condensation Hydrolysis Joins two molecules Joins two molecules One molecule loses a H+; the other a OH- to form water One molecule loses a H+; the other a OH- to form water Catalyzed by enzymes Catalyzed by enzymes One molecule is split into two One molecule is split into two The H+ and OH- from water are used to split the molecule The H+ and OH- from water are used to split the molecule Catalyzed by enzymes Catalyzed by enzymes CD ROM 1-4 CD ROM 1-4

Carbohydrates Monosaccharides = simplest sugar molecule Monosaccharides = simplest sugar molecule Soluble in water, sweet to taste Soluble in water, sweet to taste Look for –OH groups in the structural formula Look for –OH groups in the structural formula Examples Examples Glucose, fructose, galactose, deoxyribose Glucose, fructose, galactose, deoxyribose

Dissacharides Two monosaccharides sugars joined by what type of reaction? Two monosaccharides sugars joined by what type of reaction? CONDENSATION!!!! CONDENSATION!!!! Examples: Examples: Sucrose Sucrose Maltose Maltose CD ROM 2-2 CD ROM 2-2

Polysaccharides Large molecules made of many monosaccharides joined by what reaction? Large molecules made of many monosaccharides joined by what reaction? CONDENSATION!!! CONDENSATION!!! Can be broken down to release energy by what reaction? Can be broken down to release energy by what reaction? HYDROLYSIS!!! HYDROLYSIS!!! Examples: Examples: Starch = plant storage form of energy CDROM 2-3 Starch = plant storage form of energy CDROM 2-3 Cellulose = fiber-like structure found in plant cell walls Cellulose = fiber-like structure found in plant cell walls Glycogen = animal storage form of energy Glycogen = animal storage form of energy Chitin = structural; found in exoskeletons and fungal cell walls Chitin = structural; found in exoskeletons and fungal cell walls

Lipids A.K.A. Fats A.K.A. Fats Greasy, oily with little tendency to dissolve in water – They’re hydro Greasy, oily with little tendency to dissolve in water – They’re hydro Functions of Lipids Functions of Lipids Energy storage Energy storage Form membranes Form membranes Form coatings Form coatings Insulation Insulation Used as hormones Used as hormones

The “Building Blocks” of Lipids Fatty Acids – long hydrocarbon chain with a COOH group at one end Fatty Acids – long hydrocarbon chain with a COOH group at one end Unsaturated fats (oils) are room temp. Why? Unsaturated fats (oils) are room temp. Why? Double bonds between the carbons cause “kinks” in the fatty acid tails and gives them a little wiggle room Double bonds between the carbons cause “kinks” in the fatty acid tails and gives them a little wiggle room Saturated Fats are room temp. Why? Saturated Fats are room temp. Why? Single bonds between the carbons make the tails straight Single bonds between the carbons make the tails straight CD ROM 3-1 CD ROM 3-1

How do we build lipids? Add one, two or three fatty acid tails to a glycerol (alcohol) molecule by what type of reaction? Add one, two or three fatty acid tails to a glycerol (alcohol) molecule by what type of reaction? CONDENSATION!!!!! CONDENSATION!!!!! CD ROM 3-2 CD ROM 3-2

Phospholipids Two fatty acids + phosphate group + glycerol Two fatty acids + phosphate group + glycerol Main structure of the lipid bilayer in cell membranes Main structure of the lipid bilayer in cell membranes CD ROM 3-3 CD ROM 3-3

Sterols 4 Carbon Rings, but NO fatty acid tails 4 Carbon Rings, but NO fatty acid tails Cholesterol is an example; can be modified to form sex hormones and vitamin D Cholesterol is an example; can be modified to form sex hormones and vitamin D CD ROM 3-4 CD ROM 3-4

Waxes Attachment of long chain fatty acids to alcohols or carbon rings Attachment of long chain fatty acids to alcohols or carbon rings Serve as coatings for plant parts and animal coverings Serve as coatings for plant parts and animal coverings

Proteins Functions Functions Enzymes Enzymes Structural material (muscle, bones,etc.) Structural material (muscle, bones,etc.) Hormones Hormones Antibodies Antibodies Cell movement (muscle cell contraction, etc.) Cell movement (muscle cell contraction, etc.) Storage and transport agents Storage and transport agents

Amino Acid structure The “Building Blocks” of proteins The “Building Blocks” of proteins Monomers that are made of a central carbon atom, an amino group, a carboxyl group, a hydrogen and one of twenty R groups Monomers that are made of a central carbon atom, an amino group, a carboxyl group, a hydrogen and one of twenty R groups CD ROM 4-1 CD ROM 4-1

Polypeptide Chains Primary structure is the order of the amino acids linked together by peptide bonds to form polypeptide chains Primary structure is the order of the amino acids linked together by peptide bonds to form polypeptide chains What reaction links one amino acid to another? What reaction links one amino acid to another? There are 20 different amino acids There are 20 different amino acids CD ROM 4-2 CD ROM 4-2 How do amino acids differ from one another? How do amino acids differ from one another? What ultimately determines the order of the amino acids? What ultimately determines the order of the amino acids? DNA!! DNA!!

A Protein’s Final Shape Remember: Structure determines function!! Remember: Structure determines function!! Secondary structure (coil or sheet) is determined by hydrogen bonding of side groups on the amino acid chains Secondary structure (coil or sheet) is determined by hydrogen bonding of side groups on the amino acid chains Tertiary structure is the folding caused by R group interactions on the polypeptide chain Tertiary structure is the folding caused by R group interactions on the polypeptide chain CD ROM 5-1 CD ROM 5-1 Quaternary structure is the final 3-D shape that results when two or more polypeptide chains fold together Quaternary structure is the final 3-D shape that results when two or more polypeptide chains fold together CD ROM 5-2 CD ROM 5-2

Denatured Proteins Loses it’s structure, therefore it loses it’s Loses it’s structure, therefore it loses it’s Happens because weak H-bonds are broken Happens because weak H-bonds are broken High Temperatures High Temperatures pH change pH change NOT reversible NOT reversible

Mistakes in protein structure If DNA is altered, the wrong amino acid may inserted in the polypeptide chain If DNA is altered, the wrong amino acid may inserted in the polypeptide chain In Sickle Cell Anemia, valine is substituted for glutamate in the protein hemoglobin In Sickle Cell Anemia, valine is substituted for glutamate in the protein hemoglobin CD ROM 5-3 CD ROM 5-3 If a person inherits two mutated genes, the hemoglobin doesn’t have the correct shape and forms sickle shaped blood cells If a person inherits two mutated genes, the hemoglobin doesn’t have the correct shape and forms sickle shaped blood cells CD ROM 5-4 CD ROM 5-4

Nucleotides Nucleotides are the “building blocks” of nucleic acids Nucleotides are the “building blocks” of nucleic acids Nucleotide = sugar + phosphate + base Nucleotide = sugar + phosphate + base Examples: Examples: ATP (energy carrier) CD ROM 6-1 ATP (energy carrier) CD ROM 6-1 NAD+ and FAD (electron carriers) CD ROM 6-2 NAD+ and FAD (electron carriers) CD ROM 6-2 Kinds used to build DNA/RNA Kinds used to build DNA/RNA

Nucleic Acids Four different kinds of nucleotides are connected together Four different kinds of nucleotides are connected together What reaction joins nucleotides together? What reaction joins nucleotides together? Examples: Examples: DNA = double stranded; contains hereditary instructions CD ROM 6-3 DNA = double stranded; contains hereditary instructions CD ROM 6-3 RNA = single stranded; functions in translating the code to build proteins CD ROM 6-4 RNA = single stranded; functions in translating the code to build proteins CD ROM 6-4

End of Chapter 3