Relating To Fats

Question 1

What is the difference between elongation and desaturation of fatty acids?

Answer 1

Elongase enzymes add carbon atoms to preformed fatty acids -

Conversion of SFA into MUFA or PUFA occurs in the process of desaturation which is adding additional double bonds into a fatty acid (desaturase)

Question 2

Functions of Fatty Acids (12)

Answer 2

• Fluidity and chemical activity of cell membranes
• synthesis of prostaglandins
• regulate oxygen use, electron transportation and energy production
• help to form haemoglobin
• support the production of digestive enzymes
• help make the lubricants of joints
• help transport cholesterol in the blood
• help to generate electrical currents and keep the heart rate regular
• needed by the tissues of the brain, retina, adrenal glands and testes
• help balance the immune system and prevent allergies
• ensure proper nerve transmission especially in the brain
• ## bone formation and repair

Question 3

What is the difference between lipoprotein lipase and enzyme-hormone-sensitive lipase in the utilisation of triglycerides?

Answer 3

Lipoprotein lipase promotes lipid storage in the adipocyte

Enzyme Hormone sensitive lipase release lipids from storage in adipocyte.

Question 4

What is cholesterol?

Answer 4

Cholesterol is a steroid (which are a type of lipid) and a waxy compound produced by the liver. It is a vital part of our cell membranes.

It is a precursor for Vit D, steroid hormones such as testosterone, cortisol, estrogen and bile salts.

It’s also found in the blood where it is part lipid part protein in the form of HDL and LDL.

Question 5

What are eicosanoids?

Answer 5

Hormone like substances that get converted from some PUFAs stored in the membrane phospholipids. They mediate a variety of cellular processes like smooth muscle contractions, blood clotting, inflammatory cascade and vasodilation/restriction.

Question 6

Functions of lipids (fat in general)

Answer 6

Source of energy and energy storage (as triglycerides in adipose tissue)
Insulation and protection of body parts (visceral - kidneys)
Synthesis of hormones: steroids and eicosanoids (prostaglandins)
In particular cholesterol: basis of sex hormones and cortisol, precursor for Vit and bile acids
Component of cell membranes and cell signaling (inositol phospholipids and sphingolipids)
Phospholipids act as emulsifiers (keep fats suspended in blood/body fluids)