DHN 212 exam 2 study
Why are fats important in cooking and in the body? correct answers In cooking, they
provide flavor, texture, appearance, and are emulsifiers.
In the body, they insulate, serve as an energy source, are part of the cell membrane,
and can be made into cholesterol for bile production.
Are lipids organic? correct answers Yes
What are the three general categories of lipids? correct answers Triglycerides,
phospholipids, and sterols
Describe the parts of a triglyceride. correct answers 1 glycerol (three carbon sugar
backbone) + 3 fatty acids (MUFA, PUFA, SFA)
Compare and contrast the general characteristics of saturated and unsaturated fatty
acids - structures, sources, health effects. correct answers Saturated: means that all
the carbons on a fatty acid have a hydrogen; no double bond; increases risk for heart
disease. Ex: butter, Parmesan cheese, whole milk, whipped cream.
Unsaturated: liquid at room temperature; can be either monounsaturated (1 double
bond) or polyunsaturated (2+ double bonds). MUFAs may decrease risk for heart
disease. Ex of MUFA: olive oil, canola oil, avocado. Ex of PUFA: Omega-3 and omega-
6.
In general terms, describe the FA composition of canola oil, olive oil, butter fat, and
coconut oil. correct answers Canola oil: MUFA, PUFA, SFA.
Olive oil: MUFA, SFA, PUFA.
Butter fat: SFA, MUFA, PUFA.
Coconut oil: SFA, MUFA, PUFA.
Draw the structure of an 18-carbon saturated FA. correct answers see review sheet
What are the health benefits of consuming omega-3 fatty acids? correct answers
Reduces the risk for heart disease, depression, dental disease, arthritis, Alzheimer's,
etc. Improves immune function, brain development in infants, and memory.
What are food sources of omega-3 FA? correct answers Flax/chia seeds, fish, hemp
oil, walnuts, almonds, wheat germ, canola oil, breast milk, and soybeans.
What advice do you have about including fish in the diet? correct answers Aim for 2-3
servings per week, varying the type.
What is a potential concern with excessive fish intake? correct answers Mercury toxicity
, How is a trans-fat different than a saturated fat? correct answers Bond altered from a
cis to trans configuration as a result of being hydrogenated
How are most trans-fats made? correct answers Most made as a result of
hydrogenation process
What are trans fats effect on health? correct answers Increases risk for heart disease,
stroke, and type 2 diabetes. Raises LDL and lowers HDL.
How is the structure of a phospholipid different than that of a TG? correct answers
Their structures are similar except for one of the FA chains in PL's are replaced by a
phosphorous-containing group.
What are key functions of phospholipids? correct answers Part of the cell membrane &
emulsifier
What are examples of sterols? correct answers Cholesterol (bile), vitamin D, some
hormones
Why is cholesterol important to the body? correct answers It's an important structure of
the brain and nerve cells
Where is cholesterol made in the body and how much does this contribute to a person's
total blood cholesterol levels? correct answers 2/3 of total levels are made in the liver
and 1/3 is consumed from dietary animal products.
Be familiar with the steps in the process of lipid digestion and absorption (from handout
and diagram in textbook). correct answers 1. Triglycerides detected in the duodenum.
Then bile is released from the gallbladder. Bile emulsifies fat droplets.
What is the function of all lipoproteins? correct answers To transport fat in blood
What are the four parts to a lipoprotein? correct answers Phospholipid, protein,
cholesterol, triglyceride
What are the major classes of lipoproteins? correct answers Chylomicrons: How you
measure blood TG levels
VLDL: Very low-density lipoproteins that are made in the liver
LDL: Low-density lipoproteins that were converted from VLDL to LDL in blood vessels
HDL: High-density lipoproteins that are made in the liver
Contrast LDL and HDL - be able to describe in professional and layman's terms. correct
answers -> LDL is a concentrated source of cholesterol, largely impacted by SFA. If
your body doesn't need lipids as an energy source, LDL transports them from the liver
to other tissues like muscle and fat. It then clogs those blood vessels.
