Fats Flashcards
Does fat have a subunit
No
Lipids are organic compounds that are not soluble in water but they are soluble in?
Organic solvent such as alcohol
Does cholesterol requires energy to be synthesized and who synthesizes it?
They require energy to synthesize and they are synthesized by animal cells
What are the functions of cholesterol
- Precursor of highly bio active molecules
- Make esteroid hormones
- Make bile acids
What are the role of bile acid
Emulsify lipids that we ingest do that our enzymes have better access to them so that we can digest and use in our body
A fatty acid is considered
- short chain when they have … carbons
- medium chain when they have … carbons
- long chain when they have … carbons
- very long chain when they have … carbons
Short chain (2-6 carbons)
Medium chain (8-10 carbons)
Long chain (12-20 carbons)
Very long chain (20+ carbons)
Difference between stearic acid and oleic acid
Stearic acid has 18 carbons and it is saturated
Oleic acid has 18 carbons and have one double bond on the carbon 9
What are the 4 types of nuclear receptor superfamily
Steroid receptors
RXT heterodimers
Dimeric orphan receptors
Monomeric/ tethered orphan receptor
Explain steroid receptors
It is homodimer which means it is two identical subunits. The ligand can go from the cytoplasm to the nucleus. And in the nucleus they will bind to the DNA. The only one that the ligand comes form the cytoplasm
Explain RXR heterodimer
Heterodimer - 2 subunit but they are not identical.
They all have RXR and they are waiting for the metabolites to arrive and bind to them and modulate their activity
Explain dimeric orphan receptor
Orphan because we don’t know what binds to them but we know their function
Explain monomeric/retired orphan receptors
Only one monomer attach to dna
Give examples of sources of common and abundant fatty acid species
Olive oil ( rich in oleic acid C18:1)
Safflower oil ( rich in linoleic acid C18:2)
Lard , beef tallow rich in palmetic (C16:0) and stearin (C18:0)
Certain kinds of fish oil ( rich in eicosapentaenoic acid C20:5, docosahexaenoic acid C22:6)
Essential fatty acids
Human Connor make fatty acids with double bonds between carbons located at position 8 or less. They must be obtained from the diet
Give an example of essential fatty acids
Omega 3 : linolenic acid
Omega 6: linoleic acid
The essential fatty acids are substrates for a class of molecules called
Eicosanoids
Essential fatty acids are important in
Immune function, inflammatory response, blood clotting, vasodilation, kidney function, cognitive function
What happens if you have a essential fatty acid deficiency
Growth retardation, sparse hair growth, dry skin, general weakness, depression, vision problem, Increase susceptibility to infection
What happens if you have a essential fatty acid excess
Does not appear To cause severe problems ; may cause excessive bleeding ( due to slow blood clotting)
Give characteristics of saturated and unsaturated fatty acids . Ex: their form, and how we find them in room temperature
Saturated : they are straight and they are solid at room temperature (butter)
Unsaturated : they are bend and they are liquid in room temperature
Why our cellular machinery don’t know what to do with trans fats
Because our cellular machinery does not recognized they looks like stearic acid but it is not.
Trans fat are solid in room temperature
Examples of uses of fatty acids
Energy source
Structural component
Covalent modification of protein ( it will be covalent bound to protein and it will regulate the activity of the protein)
Signalling molecules ( they can provide the substrate in order to produce the signalling molecule or the second messenger)
Ligands for transcription factor
Triacylglycerols
Glycerol + 3 F.A
What is the date of diet derived lipids of cholesterol ester, triglycerides etc
So
Cholesterol ester is hydrolyzed in the lumen and it breaks down into cholesterol and fatty acids. And then the body absorbed and they are resynthesized in the enterocyte where the body can use cholesterol ester again
Triglycerides is the same thing but it will break down into fatty acids and mono glycerol
Coconut has been said that is very good for health is it true or not
It is not true coconut oil has a lot of saturated fat which is not good for you, it can increase the risk of asteroclerosis
Phospholipids is found in 2 forms which is
Micelle and bilayer ( cell membrane)
Explain the hydrolysis of phospholipids by phospholipase
The phospholipids can be acted on by many different lipases and these different lipases can cleave the phospholipids in different places and based on where they are going to cleave it, we are going to have different products and each one of this products have different roles in metabolism
What happens to the pathway when we don’t pay attention to the diet or if we have too little of the nutrients
We can be abusing with one pathway that deals with this nutrient. If we have too little we can abuse with a compensatory pathway. The body can compensate until it can’t anymore and you can have diseases
