chapter 3 Hagar Farag sec.L53 202104799
The study of organic molecules
Functional groups
Isomers
Formation of organic molecules
Types of organic molescules ( Macromolecules )
Carbohydrates
Nucleic acids
Lipids
proteins
organic molecules contain carbon
organic molecules are abundant in living organisms
1- molecules with polar bonds are water soluble 2- molecules with nonpolar bonds ( like hydrocarbons ) are not very water soluble.
condensation or dehydration reaction is used to link monomers to form polymers .
Hydrolysis reaction is used to break polymers down into monomers.
The both types of reactions are catalyzed by enzymes.
Functional groups are defined by the groups of atoms with specila chemical features that are functionally important.
Each type of functional group exhibits the same properties in all moleecules in which it occurs.
There are 9 types of functional groups
Mehtyl (-CH3)
Phosphate (-PO4-2)
Sulfate (-SO4-)
Sulfhydryl (SH)
Amino (-NH2)
Carboxyl (-COOH)
Aldehyde
Carboxyl (-OH)
Hydroxyl (-OH)
two molecules with an identical molecular formula but different structures and characteristics
Two types of isomers
Structural isomers
stereoisomers
contain the same atoms but in different bonding relationships
Cis-trans isomers : positioning around double bond
Enantiomers: mirror image molecules
Identical bonding relationships, but the spital positioning of the atoms differs in the two isomer
Composed of carbon, hydrogen, and oxygen atoms within a hydroxyl group .
Three types of carbohydrates
Disaccaharides
Polysaccaharides
Monosaccharides
Glucose isomers
glucose and galactose
Α- and β- glucose , D- and L- glucose
Composed of two monosaccharides
Examples ; sucrose (glucose+fructose), maltose (glucose+glucose), and lactose(glucose+galactose) .
Simplest sugars such as glucose, ribose, and deoxyribose
Two types of polysaccahrides
contain many monosaccharides linked together
storage
structural
citin (sugeries and insicts), cellulose (cell wall)
starch (plant) , glycogen (human)
composed of hydrogen and carbon atoms
nonpolar and insoluble in water
4 types of lipids
fats (triglycerides)
phospholipids
steroids
waxes
glycerol + 3 fatty acids
saturated and unsaturated fatty acids
glycerol + 2 fatty acids + phosphate group
amphipathic molecules ( head and tail )
4 interconnected rings of carbon atoms
special biological properties due to differences in structurs
very insoluble in water
composed of carbonn,hydrogen,oxygen,nitrogen and small amounts of other molecules
amino acids
create polypeptide
proteins
According to chapter 12, by gene expression , proteins could be :
functional proteins
structural proteins
enzymes
hormone ( steroids )
cell wall (plant)
in cellular membrane
in cytoplasm's organells
protein structures
tertiary structure
quaternary structure
secondary structure
primary structurs
single polypeptide
protein-protein interactions
ionic bonds factor
hydrophobic effects factor
hydrogen bonds factor
van der waals factor
RNA
DNA
stores genetic information
According to chapter 12, during transcription it produces an RNA copy of DNA , which makes mRNA that its function is too carry the information to ribosomes to the symthesis of polypeptidess
2 strands
1 strand