L.3 - lipids & nucliec acids Flashcards
What group of cpds are lipids in?
- heterogeneous group of cpds
What does lipids consist of?
Carbon, hydrogen (hydrophobic) and few oxygen
When are lipids soluble and non soluble?
Soluble in non-polar solvents (such as ether, chloroform)
Generally insoluble in water
What are the 5 important lipids?
- fats
- phospholipids
- carotenoids
- waxes
- steroids
What are the roles of lipids/& function?
- energy storage
- hormone
- vision
- protection
- cell membranes
What are triacylglycerols (fats)
- most abundant lipids in living organisms
- the main storage lipid
- when metabolized, yields 2x as much energy as carbs
- carbs and proteins can be transformed by enzymes into fats
What is the structure of triacylglycerol (fatty acid)
Look at diagram & draw
What are the types of fatty acids?
- Saturated - contain max possible number of hydrogen atoms
- unsaturated - include 1 or more adjacent pairs of carbon atoms joined by a double bond
- monounsaturated - one double bond
- polyunsaturated- more than 1 double bond
What type of lipids are phospholipids? What is its function?
- amphipathic lipids
- 2 ends differ physically and chemically
- functions as fundamental components of cell membranes
Know the phospholipid diagram !
!!!!
Phospholipid vs phospholipid bilayer?
Phospholipid
• Consists of a hydrophobic tail made up of two fatty acids and a hydrophilic head which includes a glycerol bonded to a phosphate group which intern is bonded to an organic group that can vary.
Phospholipid bilayer
• Phospholipids form lipid bilayers in which the hydrophilic heads interact with water and the hydrophobic tails are in the bilayer interior.
What pigments do carotenoids give off?
- orange and yellow
Which macromolecule are carotenoids classified into?
- lipids
What role do carotenoids play?
- a role in photosynthesis
What do carotenoids consist of?
- isoprene units
What do animals convert carotenoids into?
- vitamin A
Know the structures of isoprene subunit, beta carotene, point of cleavage, vitamin A, retinal
!!!! (SLIDE 13)
What is the structure of steroids?
- carbon atoms in 4 attached rings
What do steroids consist of?
- isoprene units.
Whaat are the 3 main examples of steroids?
- cholesterol - essential components of animal cell membrane
- cortisol - steroid hormone secreted by the adrenal glands
What are steroids involved in?
A regulating metabolism
What is the function of nucleic acids?
- transmits hereditary information
- determine what proteins a cell manufacturers
What are the two classes of nucleic acids found in cells?
- DNA (deoxyribonucleic acid)
- RNA (ribonucleic acid)
Nucleic acids are polymers of…
Nucleotides
What are the components of nucleotides
- 5 carbon sugar - dna or rna
- one of more phosphate groups
- nitrogenous base of either a double ring purine or a single ring pyrimidine
What are the purines and what are the pyrimidinds?
Purines - adenine & guanine
Pyrimidines - cytosine & thymine & uracil
What nitrogen bases are found in dna and what are found in rna?
cytosine & thymine - DNA ONLY
uracil - RNA ONLY
adenine & guanine - BOTH
What is DNA?
- a double started helix (2 chains)
- G-C
- A-T
What is RNA?
- single stranded (one chain)
- nucleotides are joined by phosphodiester linkages
Study gene expression (transcription!)
What is ATP?
- high energy currency of the cell
What is the structure of ATP (adenosine tri phosphate)
(Memorize how diagram looks like)
- gamma phosphate group
- alpha phosphate group
- beta phosphate group
- ribose
- nitrogen base
What is cyclic AMP? What is its function?
- a nucleotide
- cyclic adenosine monophosphate (cAMP)
- cell signalling
- transfers the effects of hormones into cells
- example: glucagon & Adrenalin which cannot pass through the plasma membrane. It is also involved in the activation of protein kinases.
