Lipids Study Guide

Question 0

Cis and trans

Answer 0

Stereoisomerism orientation of the functional groups. Functional groups on the same side are referred to as cis, whereas trans is on opposite sides.

Question 1

Micelle

Answer 1

Aggregate of surfactant molecules dispersed in a liquid colliod.

Question 2

Lipase

Answer 2

Enzyme that is involved in the digestion of fats with the hydrolysis of ester bonds.

Question 3

What at the functions of lipids?

Answer 3

-Dietary energy supply -Source of heat, insulation, and protection for body. -source of essential fatty acids -serve as carrier for adsorption of fat soluble vitamins.

Question 4

Describe the process of fat digestion.

Answer 4

Lipase produced in pancreas attacks fatty acids on 1 and 3 which contain a glycerol backbone. Are hydrophobic so micelles form and surround hydrophobic molecules with hydrophilic end pointing outwards which allows transport to liver by the assistance of portomicrons and then to target tissues. Once they are absorbed the enter the portal vein into blood.

Question 5

Why is cholesterol important for poultry?

Answer 5

Cholesterol is produced form acetate in the liver. Cholesterol then acts as a precursor to hormones which are vital for bodily functions in poultry.

Question 6

List the deficiency signs of a fatty acid deficiency.

Answer 6

Skin lesions Hair loss Reduced growth rate Fatty liver

Question 7

What are the factors influencing melting pint of fat?

Answer 7

The melting point of fat is influenced by saturated vs unsaturated fats. Unsaturated fats will either be in the cis or trans formation. Trans formation is much stronger and packs more tightly together compared to cis formation. Saturated fats are less vulnerable to rancidity and are more solid at room temperature than unsaturated fats. Saturated is single bond carbon with two hydrogen. Unsaturated fatty acid is double bond with hydrogen removed.

Question 8

Fats contain

Answer 8

2.25 the amount of energy than carbohydrates and protein.

Question 9

Lipid Classification

Answer 9

Simple lipids

• Fatty acids

– Short chain: Water soluble (acetate)

– Long chain: Saturated and Unsaturated

– Specialized

• Triglycerides
• Diglyceride
• Monoglyceride

(unsaturated = double bonds cause lack of maximum number of hydrogens on carbons).

Question 10

Lipid Classification

Answer 10

Compound lipids

Comprised of groups other than fatty acids

• Lecithin - vitamin
• Glycolipid - carbohydrate
• Sulfolipid - sulfate
• Lipoprotein - protein

Question 11

Lipid Classification

Answer 11

Other lipids

• Wax
• Steroids

– Cholesterol

– Carotenoids

Question 12

know the difference between saturated and unsaturated fatty acids

Answer 12

• Saturated fatty acid

– Single bonds

– Carbon with two hydrogen

• Unsaturated fatty acid

– Double bonds

– Hydrogen removed

Question 13

Essential fatty acids for poultry

Answer 13

• Linoleic Acid (18:2)

– Cannot be synthesized in adequate

amounts

– Poultry have a requirement

• Linolenic Acid (18:3)

– Required by aquatic species

• Arachidonic Acid (20:4)

– Synthesized from linoleic acid

– Required only if linoleic acid is marginal

Question 14

Lipid digestion

Answer 14

• Enzymatic (lipase)
• Micelle formation
• Transported to liver

– Receptor

– Synthesis

• Transported to target tissue