Fats

Question 1

Does fat have a subunit

Answer 1

No

Question 2

Lipids are organic compounds that are not soluble in water but they are soluble in?

Answer 2

Organic solvent such as alcohol

Question 3

Does cholesterol requires energy to be synthesized and who synthesizes it?

Answer 3

They require energy to synthesize and they are synthesized by animal cells

Question 4

What are the functions of cholesterol

Answer 4

1. Precursor of highly bio active molecules
2. Make esteroid hormones
3. Make bile acids

Question 5

What are the role of bile acid

Answer 5

Emulsify lipids that we ingest do that our enzymes have better access to them so that we can digest and use in our body

Question 6

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

Answer 6

Short chain (2-6 carbons)
Medium chain (8-10 carbons)
Long chain (12-20 carbons)
Very long chain (20+ carbons)

Question 7

Difference between stearic acid and oleic acid

Answer 7

Stearic acid has 18 carbons and it is saturated
Oleic acid has 18 carbons and have one double bond on the carbon 9

Question 8

What are the 4 types of nuclear receptor superfamily

Answer 8

Steroid receptors
RXT heterodimers
Dimeric orphan receptors
Monomeric/ tethered orphan receptor

Question 9

Explain steroid receptors

Answer 9

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

Question 10

Explain RXR heterodimer

Answer 10

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

Question 11

Explain dimeric orphan receptor

Answer 11

Orphan because we don’t know what binds to them but we know their function

Question 12

Explain monomeric/retired orphan receptors

Answer 12

Only one monomer attach to dna

Question 13

Give examples of sources of common and abundant fatty acid species

Answer 13

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)

Question 14

Essential fatty acids

Answer 14

Human Connor make fatty acids with double bonds between carbons located at position 8 or less. They must be obtained from the diet

Question 15

Give an example of essential fatty acids

Answer 15

Omega 3 : linolenic acid
Omega 6: linoleic acid

Question 16

The essential fatty acids are substrates for a class of molecules called

Answer 16

Eicosanoids

Question 17

Essential fatty acids are important in

Answer 17

Immune function, inflammatory response, blood clotting, vasodilation, kidney function, cognitive function

Question 18

What happens if you have a essential fatty acid deficiency

Answer 18

Growth retardation, sparse hair growth, dry skin, general weakness, depression, vision problem, Increase susceptibility to infection

Question 19

What happens if you have a essential fatty acid excess

Answer 19

Does not appear To cause severe problems ; may cause excessive bleeding ( due to slow blood clotting)

Question 20

Give characteristics of saturated and unsaturated fatty acids . Ex: their form, and how we find them in room temperature

Answer 20

Saturated : they are straight and they are solid at room temperature (butter)

Unsaturated : they are bend and they are liquid in room temperature

Question 21

Why our cellular machinery don’t know what to do with trans fats

Answer 21

Because our cellular machinery does not recognized they looks like stearic acid but it is not.

Trans fat are solid in room temperature

Question 22

Examples of uses of fatty acids

Answer 22

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

Question 23

Triacylglycerols

Answer 23

Glycerol + 3 F.A

Question 24

What is the date of diet derived lipids of cholesterol ester, triglycerides etc

Answer 24

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

Question 25

Coconut has been said that is very good for health is it true or not

Answer 25

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

Question 26

Phospholipids is found in 2 forms which is

Answer 26

Micelle and bilayer ( cell membrane)

Question 27

Explain the hydrolysis of phospholipids by phospholipase

Answer 27

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

Question 28

What happens to the pathway when we don’t pay attention to the diet or if we have too little of the nutrients

Answer 28

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