Chapter 5 Nutrition Lipids
What enzyme plays an important role in fat digestion?
Lipase
What is LDL and what is it's purpose?
Low density lipoprotein. It's primary function is to transport cholesterol to tissues. (bad)
Define Omega -3, -6 and -9
3 Essential fatty acid, alpha-linoleic acid 6 Essential fatty acid, linoleic acid 9 nonessential fatty acid
How many kilocalories per gram are in fat
9 calories/gram
Lipids contain how many calories/gram
9 calories/gram
What is triglyceride
A molecule consisting of 3 fatty acids bonded to a glycerol. Major form of lipid in food and the body
What is EPA
Eicosapentaenoic Acid high in fatty fish
What are sterols?
Multi-ring structure that can be produced by the body. Cholesterol is a common example
Chemical structure of Sterol
Multi-ringed compound with a hydroxyl group
Systolic vs. Diastolic Blood pressure
Systolic - pressure in the arterial blood vessels associated with pumping of the blood from the heart Diastolic - pressure in the arterial blood vessels when the heart is between beats
Atherosclerosis
The result of a buildup of cholesterol in the blood vessels. Greatly increases the risk of cardiovascular disease.
What are the major functions of fatty acids and triglycerides in the body?
Transport fat-soluble vitamins, energy storage and insulation
Main form of energy storage
Triglycerides
Types of lipids (3)
Triglycerides, cholesterol, saturated fatty acids
4 types of lipids
Triglycerides, phospholipids, sterols and cholesterol
Which is 'good' and 'bad' fats
Unsaturated is a good fat Saturated is a 'bad' fat
What is VLDL
Very Low Density Lipoprotein. Carries lipids made and taken up by the liver to the cells
What is cholesterol
Waxy lipid found in all body cells. Can form certain hormones and bile acids.
Steps of dietary fat absorption
1. Glycerol, monoglycerides and fatty acids are absorbed from the lumen of the small intestine into the small intestinal cells. 2. Triglycerides are reassembled within the cells lining the small intestine. 3. Triglycerides are packaged into chylomicrons. 4. Chylomicrons enter the lymphatic system
Steps of fat digestion and absorption from the mouth to the small intestine
1. Some lipase is released by the salivary glands and stomach 2. Salivary lipase and gastric lipase begin digestion short-chain fatty acids in stomach. 3. Bile emulsifies the fats. 4. Pancreatic lipase digests long-chain fatty acids and triglycerides. 5. Triglycerides are broken down and absorbed in the small intestine
The acceptable range set by the Food and Nutrition Board for lipids is what percent?
20-35%
What is chylomicron?
Carries dietary fat from the small intestine to the cells.
Chemical structure of Fatty Acids
Chain of carbons flanked by hydrogens
What is DHA?
Docosahexaenoic Acid. High levels are found in fatty fish
Phospholipid
Forms lipid bilayer of cell membrane. Can be produced in the body. Lecithin is an example of a phospholipid
Chemical structure of Phospholipid
Glycerol backbone with fatty acids and at least one phosphorus-containing group
Chemical structure of Triglycerides
Glycerol backbone with three fatty acids
What is HDL and what is it's purpose?
High Density Lipoprotein. It roams the bloodstream and picks up cholesterol from dying cells and transports it back to the liver. (good)
Difference in chemical structure between saturated and unsaturated fat?
Saturated fat contains no carbon double bonds. Unsaturated fat has one or more carbon double bonds.
Why do food manufacturers use the process of hydrogenation?
to convert liquid oils into more solid fats.