Ch. 24 Nutrition & Metabolism Flashcards
A major means for conserving heat is _____.
increased convective loss
enhanced sweating
increased metabolic rate
vasoconstriction of cutaneous blood vessels
vasoconstriction of cutaneous blood vessels
During glycolysis, glucose must be activated by how many ATP molecules?
one two three five ten
two
Most vitamins _____.
function as coenzymes in the body
are carbohydrates
are used as building blocks for the body
are metabolized to make ATP
function as coenzymes in the body
One function of vitamin A is to ______.
help with calcium absorption transfer electrons in cellular respiration form visual pigments synthesize DNA assist in blood clotting
form visual pigments
Retinol in the visual pigments is derived from vitamin ___.
A
The hormone responsible for setting the basal metabolic rate is _____.
thyroxine glucagon melanin insulin melatonin
thyroxine
The site of electron transport is the _____.
mitochondrial matrix Golgi body mitochondrial inner membrane (cristae) mitochondrial outer membrane cytoplasm
mitochondrial inner membrane (cristae)
The main integrating center for thermoregulation is located in the _____.
mitochondrion spinal cord thymus gland hypothalamus liver
hypothalamus
Which coenzyme is reduced in both glycolysis and the Krebs cycle?
NAD vitamin A FAD manganese coenzyme A
NAD
Which element below is considered a trace mineral?
potassium chromium sodium phosphorus chlorine
chromium
Which lipoprotein contains the most cholesterol?
chylomicron HDL IDL VLDL LDL
LDL
LDLs are about ___% cholesterol.
45
Nutritionally incomplete proteins are low in _____.
one or more of the essential amino acids
one or more of the major vitamins
one or more of the coenzymes
one or more of the essential fatty acids
one or more of the essential amino acids
Most of the ATP produced during cellular respiration is produced by ______.
substrate-level phosphorylation oxidative phosphorylation during the chemiosmotic process glycolysis gluconeogenesis the Krebs cycle
oxidative phosphorylation during the chemiosmotic process
A function of the liver during the postabsorptive state is ______.
to store excess glucose by glycogenesis electron transport to release glucose glycolysis lipogenesis to mobilize glucose reserves by glycogenolysis
to mobilize glucose reserves by glycogenolysis
The hormone that controls essentially all events of the absorptive state is ______.
ADH thyroxine calcitonin glucagon insulin
insulin
Which of the following factors makes it harder for an obese person to lose weight?
an increase in alpha receptors (the kind that favors fat accumulation) in fat cells
an increase in metabolism that increases appetite
an increase in thyroxine levels as fat levels accumulate
an increase in taste receptors
an increase in heat loss from the body that requires more food intake
an increase in alpha receptors (the kind that favors fat accumulation) in fat cells
Which of the following is NOT a physiological response to hypothermia?
dehydration reduced heart rate drowsiness reduced respiratory rate shivering
dehydration
A kilocalorie is the amount of energy ______.
stored in 1 kilogram of water
needed to move 1 kilogram of water 1 meter
needed to heat 1 kilogram of water 1°C
needed to heat 1 kilogram of water 1°F
needed to heat 1 kilogram of water 1°C
Essential nutrients refer to nutrients that are _____.
only found in grains
synthesized every day in the body
stored in the body for times of starvation
limited in synthesis and therefore must be consumed
limited in synthesis and therefore must be consumed
Prolonged high protein intake can lead to ______.
a negative nitrogen balance
kidney damage
muscle building
loss of bone mass
loss of bone mass
Prolonged high protein intake can lead to loss of bone mass due to ___ imbalance.
pH
Which of the following substances is considered a provitamin?
iron
vitamin D
beta-carotene
niacin
beta-carotene
Which of the following fat-soluble vitamins is NOT stored in the body?
vitamin A
vitamin K
vitamin E
vitamin D
vitamin K
The final product of glycolysis is _____.
glyceraldehyde 3-phosphate
two FAD molecules
two molecules of pyruvic acid, two molecules of NAD+, and a net gain of two ATP
two molecules of acetyl coenzyme A and two molecules of carbon dioxide
two molecules of pyruvic acid, two molecules of NAD+, and a net gain of two ATP
Cyanide acts as a poison by _____.
interfering with the flow of electrons in the electron transport chain
blocking glycolysis
abolishing the proton gradient by making the cristae membrane permeable to H+
irreversibly binding to oxygen
interfering with the flow of electrons in the electron transport chain
During fasts lasting several weeks, blood glucose is maintained by _____.
gluconeogenesis
glycolysis
glycogenolysis
lipolysis
gluconeogenesis
A low-density lipoprotein contains ______.
a high amino-acid content
a low cholesterol content
a high protein content
a high lipid content
a high lipid content
The role of ______ is to transport excessive cholesterol from peripheral tissue to the liver, where it is broken down and becomes part of bile.
chylomicrons
very low-density lipoproteins
low-density lipoproteins
high-density lipoproteins
high-density lipoproteins
The official medical measurement of obesity is the _____.
body mass index
proportion of LDLs to body weight
basal metabolic rate
proportion of bone density to weight
body mass index
_____ acts to suppress appetite by inhibiting _____, which is the most powerful known appetite stimulant.
Leptin; neuropeptide Y
Serotonin; adrenaline
Insulin; glucagon
Growth hormone; lipase
Leptin; neuropeptide Y
Which of the following statements about “redox” reactions in human metabolism is correct?
Oxidized substances lose oxygen.
Oxidized substances gain energy.
The substance being reduced loses an electron.
Coenzymes accept hydrogen.
Coenzymes accept hydrogen.
Which of the following is a micronutrient?
carbohydrate
mineral
lipid
protein
mineral
glucose
exclusive energy source for neurons
protein
used to build enzymes
minerals
may be incorporated into structures to make them stronger
cholesterol
serves as a precursor to hormones and maintains the fluidity of the plasma membrane
vitamins
can function as coenzymes
A person who is starving is likely to exhibit _____.
nitrogen balance
negative nitrogen balance
positive nitrogen balance
neutral nitrogen balance
negative nitrogen balance
T/F
Fat-soluble vitamins can be toxic if consumed in large quantities.
True
Which of the following is an example of catabolism?
lipid synthesis
absorbing nutrients into the blood from the intestines
cellular respiration
using amino acids to make a protein
cellular respiration
T/F
A substance that is reduced has lost an electron.
False
Which of the following is NOT a characteristic of glycolysis?
Glycolysis occurs in the cytosol of a cell.
The final products of glycolysis include two molecules of pyruvic acid.
Glycolysis produces a net gain of 2 ATP molecules per glucose molecule.
Glycolysis requires oxygen.
Glycolysis requires oxygen.
Which of the following is a characteristic of the citric acid (Krebs) cycle?
The citric acid cycle generates a rich supply of the reduced coenzymes, NADH and FADH2.
The citric acid cycle is an anaerobic pathway.
Pyruvic acid directly enters the citric acid cycle.
The citric acid cycle occurs in the cytosol of the cell.
The citric acid cycle generates a rich supply of the reduced coenzymes, NADH and FADH2.
The final electron acceptor in the electron transport chain is _____.
CO2
oxygen
water
NADH
oxygen
As proteins are broken down for energy, _____ is generated; the liver then converts this potentially toxic intermediate into _____.
ammonia; glucose
urea; water
acid; ammonia
ammonia; urea
ammonia; urea
In the absorptive state, _____.
insulin serves as the main regulatory hormone
catabolism exceeds anabolism
glycogen is broken down to release glucose
fats are the main energy fuel
insulin serves as the main regulatory hormone
In the postabsorptive state, ______.
anabolism exceeds catabolism
glucose is the main energy source
insulin serves as the main regulatory hormone
glycogen is broken down to release glucose
glycogen is broken down to release glucose
_____ are considered “good” cholesterol; high blood levels of this cholesterol are thought to be beneficial.
VLDLs
Chylomicrons
LDLs
HDLs
HDLs
Which of the following is considered a long-term regulator of feeding behavior?
blood concentrations of amino acids and fatty acids
stimulation of stretch receptors
leptin levels
cholecystokinin (CCK) levels
leptin levels
T/F
The body’s overall rate of energy output is called the basal metabolic rate.
False
Which of the following would raise body temperature?
evaporation
thyroxine
dilation of cutaneous blood vessels
sweating
thyroxine
