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The chemical basis of life - Coggle Diagram
The chemical basis of life
Carbon atom and organic molecules
Organic molecules
Large complex organic molecules are macromolecules
Formation
Joined by dehydration: molecule of water is removed each time new monomer is added
Broken apart by hydrolysis: molecule of water is added each time monomer is released
Carbon atom
Have 4 electrons in the outer shell
Can make up to four bonds
Bonds polarity
Polar : water soluble (C—O)
Nonpolar : not very water soluble (C—H)
Main component of organic molecules
Isomers
Structural isomers: same atoms with different bondings
Stereoisomers
Enantiomers: mirror image molecules
Cis-trans isomers : position around double bond
Functional groups
Features
Groups of atoms with special chemical properties
Exhibit the same properties in all molecules in which it occurs
Types
Amino
Ketone
Aldehyde
Caboxyl
Hydroxyl
Methyl
Phosphate
Sulfate
Sulfhydryl
Major Types of Macromolecules
Proteins
Atoms: C,H,O,N,some S
Monomers: amino acids
Structure: amino group, carboxyl group, variable side chain that determines structure and function
Bond: peptide bond
Formation
Secondary structure: folded sequence caused by hydrogen bonds
a helix
B pleated sheet
Primary structure: linear sequence of amino acids encoded by genes
Tertiary structure: secondary structure and random coiled regions fold into 3D shape
which is the final level of structure for single polypeptide
Quaternary structure:
made of two or more polypeptides
multimeric: composed from different polypeptides
Formed from several copies of the same polypeptide
Nuclic acids
Function: storage, expression and transmission of genetic material
Classes
DNA: stores genetic information encoded in the sequence of nucleotide ( double stranded )
RNA: decodes DNA into instructions for synthesizing polypeptide ( single strand )
Monomer: nucleotide ( five carbon sugar+ phosphate + nitrogen base )
Carbohydrates
Atoms : C,H,O
Monomer : monosaccharides
Hexose(6carbon)
Pentoses (5carbon)
Classification
Monosaccharides
Disaccharides
Polysaccharides
Bond : glycosidic bond
Function
Energy storage
Plant: starch
Animals: glycogen
Structural
Plants : cellulose
Animal: chitin, glycosaminoglycans
Branching
Unbranched
Moderately branched
Highly branched
Lipids
Atoms: C,H,some O
nonpolar molecules
Classification
Fats
Formation: 3 fatty acids bound to glycerol by dehydration
Types
Saturated : all carbons linked by single bonds
solid in room temperature
Un Saturated : one or more double bond
liquid in room temperature
Cis : formed naturally
Trans: formed artificiallly
linked to diseases
Function
Energy storage
Structural: cushions under the skin
Bond: peptide bond
Phospholipids
Formation: glycerol, two fatty acids, phosphate group
Properties: amphipathic
Phosphate head: polar ( hydrophilic)
Fatty acid tail: nonpolar ( hydrophobic)
Waxes
Steroids
Structur
main skeleton for all steroids is four interconnected rings of carbon
Tiny differences in structure result in different biological properties
ex:cholesterol can be converted to other steroids by modifying side groups
Insoluble in water