ch. 3,4,5,6
Which of the following is true about protein?
It is made up of combinations of approximately 20 amino acids.
What is meant by the amino acid sequence of a protein?
Order of appearance of amino acids in the peptide chain
Which of the following is a true statement about the digestion and absorption of proteins?
Polypeptide chains are digested to yield individual amino acids, which can be absorbed into the blood.
GI tract
Sites in the body for digestion and absorption of nutrients; consists of mouth, esophagus, stomach, small intestine, large intestine, rectum, and anus.
Omega 6 fatty acid
an unsaturated fatty acid with the first carbon-carbon double bond at the sixth carbon atom from the methyl end
Metabolism can be categorized into 2 types of reactions, __________________ puts smaller molecules together to build larger ones and, therefore requires energy. The other type of reaction, _________________, takes molecules apart and, therefore releases energy.
anabolic, catabolic
linoleic acid, an omega-6 fatty acid, is converted by the body into
arachidonic acid
______ are lipoproteins made of dietary fat surrounded by a shell of cholesterol, phospholipids, & protein; their role is to transport fat that has been absorbed by the GI tract.
chylomicrons
immediately after a meal, newly absorbed dietary fats appear in the blood as
chylomicrons
The nitrogen from amino acid breakdown is
converted to urea
Treating a protein with acid, heat, or agitation will cause ________, meaning that the three-dimensional structure of the protein has been altered.
denaturation
digestive system
digestion, absorption and controlled by nervous system and hormones from endocrine sys.
Maltose
disaccharide
John Fibernugget wants to increase his fiber intake. Which of the following would be the safest way for him do this?
eating more fruits & veggies & not removing the edible peels
Sometimes phospholipids are used in commercial salad dressings to suspend vegetable oil in water. In this case, phospholipids are serving as _______________.
emulsifiers
which hormone is released during stressful times to increase blood glucose levels, making more energy available for use
epinephrine
the symptoms of diabetes may occur suddenly & may include
extreme thirst & excessive urination
the main problem with the fat replacer olestra is that it can reduce absorption of
fat-soluble vitamins
the simplest form of lipid; a carbon chain, flanked by hydrogen, w/ an acid group at one end & a methyl group at the other end
fatty acid
polyunsaturated fatty acid
fatty acid with two or more carbon-carbon double bonds
Polysaccharides that cannot be digested by human digestive enzymes, & therefore cannot be absorbed, are called
fiber
The most reliable source of vitamin B-12 for the vegan would be
fortified soybean milk
After absorption, galactose is converted to ________ in the liver.
glucose
starch consists of hundreds & perhaps thousands of which molecules?
glucose
Soluble (vicious) fiber
help to lower blood cholesterol
Which lipoprotein is responsible for picking up cholesterol from dying cells and other sources so it can be transported back to the liver for excretion?
high density lipoprotein
food manufacturers prefer to use ______ as a sweetener b/c its easy to transport, has good shelf stability, low cost, & improves food properties.
high-fructose corn syrup
In terms of heart disease risk, which of the following is true?
higher LDL= increased risk
the process of ____ changes the double bonds in unsaturated fatty acids into single bonds, giving the fat a more solid consistency
hydrogenation
Most plant proteins are ________ proteins, which means that they are low in one or more of the essential amino acids.
incomplete
diets high in trans fatty acids tend to _____ the level of LDL in the blood
increase
When eating a high-fiber diet, one should
increase fluid intake
A protein that acts as a hormone is
insulin
what's the importance of insulin?
insulin is produced by the pancreas, helps control the amount of glucose in blood
which is true about olestra
it cannot be digested; therefore, its secreted in feces.
NOT a characteristic of cholesterol
its an essential nutrient
When too little dietary carbohydrate is available to meet energy needs, ______ arise as byproducts of partial fat metabolism.
ketones
A vegetarian who excludes animal flesh but consumes milk and eggs is referred to as a
lactoovovegetarian
If a food does not contain the necessary amounts of a certain amino acid to meet a body need, that amino acid is referred to as a(n)
limiting amino acid
Most lipids are transported in the blood as part of a structure called a(n) _______________.
lipoprotein
immediately after sugars are absorbed into the blood, they travel to the
liver
When blood glucose levels drop below normal, hormones signal the breakdown of ______, which releases glucose into the blood
liver glycogen
After chylomicrons leave the intestinal cells, they are transported via what system?
lymphatic
Chemical Processes involved in maintaining life• Enable us to release and use energy from foods, synthesize new organic molecules and remove waste
metabolism
Which of the following is a food that provides ample amounts of all of the essential amino acids?
milk
minimum # of grams of carbohydrate, per day, humans must consume to avoid ketosis
130
a disaccharide is formed by the chemical bonding of
2 monosaccharides
a meal providing 1,200 kilocalories contains 13 grams of saturated fat, 10 grams of monosaturated fat, & 27 grams of polyunsaturated fat. This meal provides _____% of total kcal as fat
37.5
The Food and Nutrition Board recommends that Americans consume ______ of their total calories from carbohydrates.
45%-65%
Jack weighs 176 pounds. What is his RDA for protein?
64 grams (176/2.2=80 x 0.8 =64)
saturated fatty acid
A fatty acid with no carbon-carbon double bonds
endocrine system
Glands secrete hormones that regulate processes such as growth, reproduction and cell metabolism
List at least three hormones that tend to increase blood sugar.
Glucagon, epinephrine, norepinephrine
which of the following combinations of monosaccharides is true?
Glucose & galactose form lactose
galactose
monosaccharide
Olive and canola oils contain a high percentage of ____________ fatty acids.
monounsaturated
When insulin is released, it causes
muscle and fat cells to take up glucose from the blood
the major storage sites for glycogen are the
muscles and liver
The chemical element found in all amino acids but not found in either carbohydrates or fats is
nitrogen
A _____fatty acid is a polyunsaturated fatty acid that has a double bond at the 3rd carbon from the methyl end
omega-3
a monounsaturated fatty acid contains
one double bond
Excessive sugar intake is related to development of dental caries b/c
oral bacteria produce acids that dissolve tooth enamel when they metabolize sugars.
Amylose
starch
describe the process of starch digestion
starch to maltose to glucose
Human enzymes digest proteins in which areas of the body?
stomach & small intestine
the major function of adipose tissue is to
store triglycerides
When protein consumption is in excess of body needs and energy needs are met, the excess amino acids are broken down and the energy in the molecule is
stored as fat
Which of the following is a function of protein?
synthesis of enzymes & hormones
omega-3 fatty acid
An unsaturated fatty acid with its first carbon-carbon double bond at the third carbon atom from the methyl end
best source of insoluble (nonfermentable) fiber
Broccoli
hepatic portal circulation
Drains nutrient-rich blood from digestive organs Delivers it to the liver for processing
Chylomicron
Lipoprotein made in the intestine after fat absorption
VLDL
Lipoprotein that carries cholesterol and lipids newly synthesized by the liver
HDL
Lipoprotein that picks up cholesterol from dying cells & other sources & transfers it to other lipoproteins, as well as directly to the liver
lymphatic system
Lymph is a clear fluid that eventually passes into bloodstream from the lymphatic system.
Which of the following is an essential amino acid?
Tryptophan
amylose
a long, straight glucose chain
Proteins regulate the acid-base balance of the blood by
acting as buffers.
Amino acids are absorbed via
active absorption
If the carbohydrate content of the diet is insufficient to meet the body's needs for glucose, which of the following can be converted to glucose?
amino acids
2 forms of starch found in food are
amylose & amylopectin
the glycemic index (GI) is a measurement of how a carbohydrate-containing food raises
blood glucose
Edema appears when there is a severe lack of dietary protein because
blood protein levels fall and fluid shifts into extracellular spaces.
The edema in children with kwashiorkor is the result of fluid leaking into
body tissues from the bloodstream because of decreased blood protein levels.
An essential amino acid
cannot be synthesized in the body in sufficient quantity to meet body needs.
the red blood cells & brain are 2 body tissues that derive most of their energy from
carbohydrate
most lipids are composed of
carbon, hydrogen, & oxygen
Consists of the heart, blood vessels, and blood.Transports nutrients, waste products, gases, and hormones throughout body.Plays role in immune responses and regulation of body temperature.
cardiovascular system
Describe Type 1 Diabetes Mellitus
caused by lack of insulin production
phospholipids are the main component of
cell membranes
organization of the body
cells --> tissues Tissues --> Organs Organs --> Digestive Systems
fiber
cellulose
In the case of sickle cell anemia, slight alterations in the DNA code lead to
changes in the structure of the protein hemoglobin.
which food is cholesterol free
peanut butter
In proteins, amino acids are joined by ________ bonds.
peptide
The disease phenylketonuria (PKU) illustrates how a nonessential amino acid can become conditionally essential as a result of a genetic disease. A person with PKU has a limited ability to metabolize the essential amino acid
phenylalanine
Most proteins are ________, which are composed of 10 or more amino acids.
polypeptides
Dietary fibers primarily are
polysaccharides
LDL
product of VLDL metabolism that contains primarily cholesterol
effects of sugar
prolonged exposure of the teeth to simple sugars from snacks & drinks promotes dental caries
Which section of MyPlate is the least significant source of carbohydrate?
protein
Antibodies are
proteins produced by white blood cells as part of the immune response
refers to the breakdown of fatty acids upon exposure to light, oxygen, or heat. this breakdown of fatty acids may cause disagreeable flavors & odors in food products
rancidity
plant sterols
reduce cholesterol absorption in the small intestine & lower is return to the liver
which oil contains the most polyunsaturated fatty acids
safflower oil
the major dietary fiber to be concerned about in relation to heart disease is
saturated fat
Triglyceride
three fatty acids attached to a glycerol backbone
hydrogenation produces _____ in food products
trans fatty acids
in which form are most dietary lipids found
triglycerides
Lipoproteins are composed of
triglycerides, cholesterol, phospholipids, & proteins
A person who does not eat any animal foods and consumes only plant products is a
vegan