HBIO202: FINAL EXAM QUESTIONS AND ANSWERS WITH
COMPLETE SOLUTIONS GRADED A++
lipids
composed of carbon, hydrogen, and oxygen, serve various functions such as storing
energy, insulating, transporting proteins in the blood, and structuring cell membranes
fat
most common lipid, give flaky texture to baked goods, make meats tender, provide
flavor and aromas, contribute to satiety
three types of lipids
triglycerides (fats), phospholipids, and sterols
fatty acids
chain of carbon and hydrogen atoms with acid group, over 20 variations by length
double or single bonds and number of double bonds
short chain fatty acids
up to 5 carbons
medium chain fatty acids
6-12 carbons
long chain fatty acids
13-21 carbons
very long chain fatty acid
more than 21 carbons
,saturated fatty acids
all carbons are saturated with as many hydrogen atoms as possible, solid at room
temperature
monounsaturated/trans fatty acids
one double bond, liquid at room temperature, ex: oleic acid (olive oil)
polyunsaturated/cis fatty acids
more than one double bond, ex: essential fatty acids linoleic and alpha-linolenic acids
saturated fats
no double bonds, solid at room temperature, straight shape, less healthy, animal origin
unsaturated fats
contain double bonds, liquid at room temperature, bent shape, more healthy, higher
amounts in plant products
trans fats
created in hydrogenation, make vegetable oils solid, increase shelf life, and produces
trans fatty acid isomers that are not naturally occurring
which one of the following is the unhealthy fatty acid?
unsaturated trans fatty acid
triglyceride
three fatty acids connected to glycerol, most common lipid found in foods and body,
phospholipids
two fatty acids a phosphorus group and a glycerol backbone, hydrophobic tail
lecithin
phospholipid in cell membrane, emulsifier in foods
, sterols
cholesterol, composed mainly of four connecting rings of carbon and hydrogen,
important role in cell membrane structure, precursor of important compounds in body,
not required in diet since body makes all cholesterol needed
lipid absorption
micelles break apart in the small intestine so they can be absorbed in the enterocyte
(cells of the small intestine), in the enterocyte new aggregates of triglycerides and other
lipids are formed
energy in fat
9 kcal/g
how does the body use fat
needed for absorption of fat soluble vitamins (A, D, E, K) and carotenoids, insulates
body to maintain body temp, cushions bones, organs, nerves
lipoproteins
transport fat through the lymph and blood
chylomicrons
mostly triglycerides, carry digested fat from the mean through lymph into the
bloodstream
very low-density lipoproteins (VLDL)
mostly triglycerides, deliver triglycerides from the liver to the cells
low-density lipoproteins (LDL)
bad cholesterol, mostly cholesterol, deliver cholesterol to the tissues, deposit
cholesterol on the walls of arteries
COMPLETE SOLUTIONS GRADED A++
lipids
composed of carbon, hydrogen, and oxygen, serve various functions such as storing
energy, insulating, transporting proteins in the blood, and structuring cell membranes
fat
most common lipid, give flaky texture to baked goods, make meats tender, provide
flavor and aromas, contribute to satiety
three types of lipids
triglycerides (fats), phospholipids, and sterols
fatty acids
chain of carbon and hydrogen atoms with acid group, over 20 variations by length
double or single bonds and number of double bonds
short chain fatty acids
up to 5 carbons
medium chain fatty acids
6-12 carbons
long chain fatty acids
13-21 carbons
very long chain fatty acid
more than 21 carbons
,saturated fatty acids
all carbons are saturated with as many hydrogen atoms as possible, solid at room
temperature
monounsaturated/trans fatty acids
one double bond, liquid at room temperature, ex: oleic acid (olive oil)
polyunsaturated/cis fatty acids
more than one double bond, ex: essential fatty acids linoleic and alpha-linolenic acids
saturated fats
no double bonds, solid at room temperature, straight shape, less healthy, animal origin
unsaturated fats
contain double bonds, liquid at room temperature, bent shape, more healthy, higher
amounts in plant products
trans fats
created in hydrogenation, make vegetable oils solid, increase shelf life, and produces
trans fatty acid isomers that are not naturally occurring
which one of the following is the unhealthy fatty acid?
unsaturated trans fatty acid
triglyceride
three fatty acids connected to glycerol, most common lipid found in foods and body,
phospholipids
two fatty acids a phosphorus group and a glycerol backbone, hydrophobic tail
lecithin
phospholipid in cell membrane, emulsifier in foods
, sterols
cholesterol, composed mainly of four connecting rings of carbon and hydrogen,
important role in cell membrane structure, precursor of important compounds in body,
not required in diet since body makes all cholesterol needed
lipid absorption
micelles break apart in the small intestine so they can be absorbed in the enterocyte
(cells of the small intestine), in the enterocyte new aggregates of triglycerides and other
lipids are formed
energy in fat
9 kcal/g
how does the body use fat
needed for absorption of fat soluble vitamins (A, D, E, K) and carotenoids, insulates
body to maintain body temp, cushions bones, organs, nerves
lipoproteins
transport fat through the lymph and blood
chylomicrons
mostly triglycerides, carry digested fat from the mean through lymph into the
bloodstream
very low-density lipoproteins (VLDL)
mostly triglycerides, deliver triglycerides from the liver to the cells
low-density lipoproteins (LDL)
bad cholesterol, mostly cholesterol, deliver cholesterol to the tissues, deposit
cholesterol on the walls of arteries
