BIOCHEMISTRY The chemistry of Life Chemicals that make up living things are mostly organic macromolecules belonging to the four groups Carbohydrates proteins.

BIOCHEMISTRYThe chemistry of Life

Chemicals that make up living things are mostly organic macromolecules belonging to the four groups

Carbohydrates

proteins

lipids

nucleic acids

http://mset.rst2.edu/portfolios/a/abdelmessih_m/finalproject/biochempro.ppt

Organic Molecules

Structure monomers polymers

Carbohydrates C,H,O

1:2:1

monosaccharides Polysaccharides

Proteins C,H,O,N,S Amino Acids Polypeptides

Lipids C,H,O Fatty Acids Complex fat

Nucleic Acids C,H,O,N,P Nucleotides RNA, DNA

Carbohydrates• Carbohydrates have the general formula of(CH2O)n, with abundant

hydroxyl groups(-OH). • Carbohydrates can be either a single sugar, (Click) monosaccharide

like glucose, (Click) a disaccharide like sucrose, or a series of monosaccharides

(Click) polysaccharides like Starch.

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•glucose, "blood sugar", the immediate source of energy for cellular respiration •galactose, a sugar in milk (and yogurt), and •fructose, a sugar found in honey.

Although all three share the same molecular formula (C6H12O6), the

arrangement of atoms differs in each case. Substances such as these three, which have identical molecular formulas but different structural formulas, are known as isomers.

Monosaccharides

Back Carbohydrates

+

Sucrose

Condensation Hydrolysis

Two monosaccharides can be linked together to form a "double" sugar or disaccharide by Condensation reactionThe reverse reaction is Hydrolysis where sucrose molecule is broken down into two monosaccharides, glucose and fructose.

Back Carbohydrate

+ H2O

http://www.tvdsb.on.ca/Westmin/science/sbioac/biochem/condense.htm

http://trc.ucdavis.edu/biosci10v/bis10v/media/ch02/reaction_types.html

Polysaccharides

Complex molecules composed of three or more monosaccharides

GlycogenStores glucose in animals

in the form of highly branched chain,used for quick energy.

StarchStores glucose in plant in the form of

Highly branched chain

Coiled unbranched chain

CelluloseIn the form of straight chains linked

together by hydrogen bonds.Gives rigidity and strength

to plant cellsBack Carbohydrates

Proteins Macromolecules or polymers constructed from one or more unbranched chains of polypeptide .A polypeptide chain is composed of amino acids. A typical protein contains 200–300 amino acids

The protein represented here consists of two polypeptide chains, a long one on the left and a short one on the right.

Amino acids (Click) are the building blocks (monomers) of proteins. 20 different amino acids are used to synthesize proteins. The shape and other properties of each protein is dictated by the precise sequence of amino acids in it.

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*** The important example of proteins are (Click) Enzymes.

Hydrogen

Carboxyl Group

Amino Group

Functional Group

The basic structural of an Amino Acid

VALINE

ALANINE

GLYCINE

Back TableAmino acids are joined together by a (Click) peptide bond. Back Proteins

Amino acids are joined by condensation and a water molecule is removed. It is formed as a result of a condensation reaction between the amino group of one amino acid and the carboxyl group of another.The bond formed as a result between the two amino acids is called a peptide bond and the product is called dipeptide.

Back Amino acids

Back Proteins

Back Table

http://student.ccbcmd.edu/biotutorials/proteins/peptide.html

http://michele.usc.edu/java/pept.html

http://plantsciences.montana.edu/cqlab/proteinformation.htm

Enzymes Enzymes are (Click) catalysts. Most are proteins. Enzymes bind temporarily to one or more of the reactants of the reaction they catalyze. In doing so, they lower the amount of activation energy needed and thus speed up the reaction

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In order to do its work, an enzyme must unite with at least one of the reactants(substrate). This requirement for complementarity in the configuration of substrate and enzyme explains the remarkable specificity of most enzymes. Generally, a given enzyme is able to catalyze only a single chemical reaction

Back Table

Enzymes are organic molecules that act as catalysts. They speed up chemical reactions by decreasing

the amount of activation energy.

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LipidsLarge, nonpolar organic molecules that do not dissolve in water. They have higher ratio of carbon hydrogen bonds ( that store energy) than carbon oxygen bonds.Most lipids are composed of (Click) fatty acids.

(Click) Phospholipids

Lipids

(Click) Waxes

(Click) Steroids

Complex Lipids

(Click) Triglycerides

Cholesterol

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A fatty acid is a long unbranched carbon chain with carboxyl group –COOH attached to one end.

A carboxyl group (polar,attracted to water molecules)Hydrophilic

Ahydrocarbon end(nonpolar,interact With water molecules) hydrophobic

UnsaturatedCarbon atoms make double bond.

Saturated fatty acidCarbon atoms make single bonds.

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Back

TriglyceridesThree molecules of fatty acids + a glycerol molecule

Saturated Triglycerides Unsaturated Triglycerides

Saturated fatty acids

Solid at room temperature

Ex. Animal fats

unsaturated fatty acids

Liquids at room temperature

Ex. Plant seed & fruitsBack Lipids

Two molecules of fatty acids + a glycerol moleculePhospholipids

Our cell membranes are made mostly of phospholipids arranged in a double layer with the tails from both layers “inside” (facing toward each other) and the heads facing “out” (toward the watery environment) on both surfaces( lipid bilayer). The membrane serves as barrier between the inside and outside of the cell

Hydrophilic Head

Hydrophobic Tails

Hydrophilic Head

Back Lipids

http://www.wisc-online.com/objects/ViewObject.aspx?ID=ap1101http://www.susanahalpine.com/anim/Life/memb.htm

Steroids

Composed of four fused carbon rings with various functional groups

Ex. **cholesterol

**many animal hormones like the male hormone testosterone.

WaxesLong fatty acid chain+Long alcohol chain.It forms protective layer in animal and plants

Back Lipids

Nucleic Acids Very large molecules(polymers) that store genetic information.They composed of linked monomers called (Click) nucleotides.

DNADeoxyribonucleic acid

contains information for all cell activities

RNARibonucleic acid

stores and transfer the information for protein production

Back Table

Nitrogen Base

Five CarbonSugar

Phosphate Group

Nucleotide Structure: Monomers of nucleic acids

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