Chapter 25 HW. Metabolism, Nutrition, Energetics
The vitamin that plays a role in maintaining epithelia and is required for the synthesis of visual pigments is vitamin
A
The conversion of ammonia into a less toxic substance produces
urea
When the body is relying on internal energy reserves to continue meeting its energy demands, it is in the ________ state.
postabsorptive
The formation of GTP from GDP in the citric acid cycle is an example of
substrate-level phosphorylation.
The carbon dioxide released by the lungs into the atmosphere was very likely produced within __________.
the citric acid cycle
In order to determine the LDL level in a patient's blood, it is necessary to measure
total cholesterol level, HDL level, and triglyceride level.
All of the following are true of beta-oxidation except that
lipids are converted into glycogen molecules.
Catabolism of protein is not a practical source of quick energy because of all of the following except that
most individuals have little protein to spare before harming vital organs.
The function of the citric acid cycle is to
remove hydrogen atoms from organic molecules and transfer them to coenzymes.
The removal of amino group from a protein to prepare it to enter the citric acid cycle is termed
deamination
Fatty acids that are necessary for proper health but cannot be synthesized by the body are called ________ fatty acids.
essential
Frank has diabetes mellitus and his blood pH has dropped. What is the most likely cause of his acidosis
excess ketone formation
The vitamin that is essential for the production of several clotting factors is vitamin
K
The two most important coenzymes for glycolysis and the citric acid cycle are
NAD and FAD
When NAD+ is ________ it becomes NADH. When NADH is ________ it becomes NAD+.
Reduced; oxidized
Reactions within ________ provide most of the energy needed by a typical cell.
The mitochondria
The element that is necessary for the proper function of the enzyme carbonic anhydrase is
Zinc
All of the following occur during glycolysis, except
a molecule of carbon dioxide is produced.
The lipoproteins that carry absorbed lipids from the intestinal tract to the bloodstream are
chylomicrons
The nutrients that yield the most energy per gram when metabolized are
fats
The process of synthesizing glucose from noncarbohydrates is called
gluconeogenesis
Although other nutrients can feed into the citric acid cycle, ________ yields energy the quickest.
glucose
An element that is a component of hemoglobin, myoglobin, and cytochromes is
iron
What all occurs during glycolysis?
-4 molecules of ATP are produced -a molecule of glucose is converted into 2 molecules of pyruvic acid -2 molecules of ATP are consumed -hydrogen atoms are removed from organic molecules
If the body starts to use energy sources other than carbohydrates. This would result in
-increased levels of urea in the blood -increased gluconeogenesis in the liver -ketosis and a decresaed blood pH -lipid metabolism
All of the following are true of beta-oxidation?
-it requires coenzyme A, NAD, and FAD -fatty acids break down into 2-carbon fragments -it yields large amounts of ATP -it occurs in the mitochondria
Catabolism of protein is not a practical source of quick energy b/c ...
-proteins are more difficult to break apart than lipids or carbs -the energy yield from protein is less than the yield from lipids -one of the by-products of protein catabolism is ammonia -extensive catabolism of protein threatens homeostatsis
Glycolysis produces how many pyruvate molecules and how many ATP molecules?
2 pyruvate molecules with a net gain of 2 ATP molecules
Eating disorders are common among girls and young women. They result from a psychological problem that causes inadequate or excessive food consumption. Two major eating disorders are anorexia nervosa and
Bulimia
The end products of aerobic respiration are
Carbon dioxide, water, and ATP
The first steps of catabolism generally take place in the
Cytosol
Inadequate exposure to sunlight could result in decreased amounts of vitamin ________ in the body.
D
Most of the ATP from metabolism is produced in the
Electron transport system
________ carry excess cholesterol from peripheral tissues to the liver.
High-density lipoproteins (HDLs)
On a tour of African countries, Mark contracts a bad case of traveler's diarrhea. Because he can't eat very much, his body starts to use energy sources other than carbohydrates. This would result in all of the following, except
glycogenesis
A high uric acid level (above 7.4 mg/dl) can lead to the painful condition known as
gout
About 40 percent of the energy content of nutrients is captured as ATP. The remainder is lost as __________.
heat
Physicians have found improved outcomes when forcefully cooling specific organs or the whole body prior to surgery in a process called
induced hypothermia.
More than half the heat is lost from the body indoors through the process of
radiation
