Biochemistry Flashcards
Key roles of carbohydrates
Energy source, storage, structural support & cell recognition/signalling
Most important carbohydrates
Saccharides
Monosaccharide structure
Linear
No. Of carbons in monosaccharides
Varies
Disscharides
Two monosaccharides joined together
What does branching do in polysaccharides
Increases solubility of glycogen
Provides terminal ends for enzymatic action
Heteropolysaccharides
Composed of two or more different types of monosaccharides
Hyaluronic Acid
Composed of repeating disscharide units of N-acetylglucosamine & glucuronic acid
What is hyaluronic acid a major component of
Extracellular Matrix
Synovial Fluid
Vitreous Humour
Supports Tissue Hydration
Contributes to wound healing
Function of hyaluronic acid in reproductive system
Surrounds ovulated oocyte
May regulate sperm selection/function prior to fertilisation
Function of Membrane Carbohydrates
Act as molecular tag that allows cells to recognise & communicate with each other
What are blood group antigens determined by
Specific glycoproteins & glycolipids on rbc surface
What is cell adhesion essential for
Tissue formation & pathogen recognition
What do selectins (glycoprotein) do?
Mediate adhesion of wbc to endothelial cells during the immune response
Lipids
Diverse & ubiquitous group of biological molecules which have many key biological function
What is the charge of a phospholipid?
Negative
What happens when phospholipids are added to water?
They self-assemble into double layered aggregates to shield the hydrophobic protein from water
Where are Sphingolipids abundant?
Cell membrane of lipids
In myelin sheath
What are sphingolipids essential for?
Nerve function/signalling
What does sphingolipid regulation do?
Of levels underpins cell growth differentiation & apoptosis
Plays an important role in neurodegenerative diseases, cancer & inflammatory conditions
Steroids
Characterised by a carbon skeleton consisting of four fused rings
What hormones is cholesterol a building block of?
Cortisol, Testosterone, Progesterone, Estradial & Aldosterone
Are lipids hydrophobic?
Not all but all have a hydrophobic portion
