Biomolecules Flashcards
Main functions of Carbohydrates
Primary function - short-term energy generation
Secondary function - intermediate-term energy storage
Tertiary function - structural components in cells
What 3 carbohydrates form when monosaccharides combine
Disaccharides
Oligosaccharides
Polysaccharides
Why do many common sugars exist in the cyclic form?
Ring form more energetically stable
Aldehyde or ketone can react with alcohol
What are Complex Oligosaccharides involved in
Cellular recognition processes
Bacterial and viral infections
Cancer metastasis
Intercellular recognition processes
4 key types of lipids
Fats
Steroids
Phospholipids
Eicosanoids
Main functions of lipids
Energy storage
Heat or insulation
Structural components of cell membranes
Communication
What are the two different subunits of lipids
Ketoacyl lipids
Isoprenoids
What part of the lipid is hydrophillic and non-polar
Carboxyl head group
Describe saturated fats
Single bonds between carbons
Linear appearance
Solid at room temp
Describe unsaturated fats
One or more C=C bonds
C=C double bonds gives distinct bend
reduces Tm-liquid at room temp
Describe Triacylglycerols
Glycerol head group attached to 3 fatty acid chains
Stored as cytoplasmic ‘lipid droplets’
Long term storage for energy and insulation
High in energy (5 kcal/gram higher than carbohydrates)
What are phosphoglycerates composed off
Glycerol backbone attached to 2 fatty acid chains and 1 phosphorylated alcohol
What are eicosenoids derived from
Arachidonic acid
What are the four families of Eicosenoids
Prostaglandins
Prostacyclins
Thromboxanes
Leukotrienes
Describe Steroids
Built around a 4-ringed hydrocarbon skeleton
Cholesterol is the base for all steroid hormones
Also the base for bile acids
Name 5 steroid hormones
Glucocortecoids Mineralocortecoids Androgens Eostrogens Progestogens
Name 3 sterols
Cholesterol
Ergosterol
Phytosterols
What is cholesterol
Present in mammalian cell membranes
Precursor of steroid hormones and bile acids
Where is Ergosterol present
Cell membrane of fungi
What percentage of the dry weight of most cells do proteins account for
50%
What does the basic structure of amino acid consist of
Central carbon atom Amino group Carboxylic acid group Hydrogen atom Side-chain
Explain linking of amino acids
Added on at a time Bond formed carboxyl to amino end Intrinsic directionality Condensation reaction forming a peptide bond Repeated N-C-C backbone Side chains protrude from backbone
Monomeric vs multimeric proteins
Monomeric - one polypeptide
Multimeric - more than one polypeptide
What is a nucleoside
Base linked to the sugar
What are Sphingolipids
Sphingomyelin backbone instead of glycerol
Contains unsaturated hydrocarbon chain
Complex sphingolipids are produced by the addition of head groups at the C1 hydroxyl position
What do vitamins do
Link and regulate metabolic reactions that release energy within food
Work alongside each other in groups
Enhance or impair another vitamin/minerals absorption and functioning
