Metabolism and Energy
sum of all chemical reactions in the body
metabolism
Linoleic acid and linolenic acid are examples of transport proteins. essential fatty acids. essential amino acids. non-essential amino acids lipoproteins.
essential fatty acids.
In oxidative phosphorylation, energy for the synthesis of ATP is directly obtained from the breaking of the covalent bonds in glucose. splitting of oxygen molecules. movement of hydrogen ions through channels in the inner mitochondrial membrane. combination of two atoms of hydrogen and one atom of oxygen to form water. oxidation of acetyl-CoA.
movement of hydrogen ions through channels in the inner mitochondrial membrane.
CCK triggers release of pancreatic enzymes Pancreatic alpha- amylase continues carbohydrate digestion
n/a
Lipids reach the bloodstream in chylomicrons; the cholesterol is then extracted and released as lipoproteins
n/a
When chyme arrives in the duodenum, cholecystokinin (CCK) release triggers the secretion of which enzyme? pancreatic alpha-amylase maltase gastric inhibitory peptide (GIP) salivary amylase
pancreatic alpha-amylase
A vitamin obtained from meat that is a coenzyme in amino acid and lipid metabolism is pyridoxine (B6). folic acid (folate). riboflavin. pantothenic acid. niacin.
pyridoxine (B6).
In transamination, the amino group of an amino acid is ________, yielding a different amino acid. converted to urea transferred to acetyl-CoA converted to ammonia absorbed by water transferred to another molecule
transferred to another molecule
During lipolysis, lipids are converted into glucose molecules. lipids are formed from excess carbohydrates. triglycerides are broken down into glycerol and fatty acids. triglycerides are converted into molecules of acetyl-CoA. lipids are metabolized to yield ATP.
triglycerides are broken down into glycerol and fatty acids.
Enzymes in liver cells use ammonium ions to synthesize
urea(less toxic substance)
vitamins A, E, K come from
vegetables
Impaired fat absorption in the intestine would interfere with the absorption of vitamin A. riboflavin. niacin. vitamin C. vitamin B12.
vitamin A
Which fat-soluble vitamin is essential for liver synthesis of prothrombin and other clotting factors? vitamin A vitamin E vitamin K vitamin D3
vitamin K
essential for liver synthesis of prothrombin and other clotting factors
vitamin K
Obesity is defined as a body weight more than ________ percent above the ideal body weight for an individual. 10 30 5 20 15
20
Of all the energy released in catabolism, about ________ percent is lost as heat warms the surrounding tissues. 60 10 80 40 20
60
Wally decides to go on a hunger strike to further one of his favorite causes. After many days with nothing but water you would expect to observe lowered blood pH. ketone bodies in his urine. elevated levels of glucocorticoids. All of the answers are correct. None of the answers is correct.
All of the answers are correct.
An excess of which water-soluble vitamin results in polycythemia? B3 (niacin) B2 (riboflavin) B12 (cobalamin) B6 (pyroxidine)
B12 (cobalamin)
The USDA has an interactive food recommendation program online, called the Mediterranean Diet. ChooseMyPlate. the DASH diet. Dietary Guidelines for Americans. MyPyramid.
ChooseMyPlate.
The food pyramid recommends many servings a day of dark-green and orange vegetables and citrus fruits. Which vitamin is not particularly abundant in these food groups? D C A E All of the answers are correct; folic acid
D
The vitamin that is required for proper bone growth and for calcium absorption and retention is vitamin A. B. C. D. E.
D
________ carry excess cholesterol from peripheral tissues to the liver. Low-density lipoproteins (LDLs) Very-low-density lipoproteins (VLDLs) Very-high-density lipoproteins (VHDLs) High-density lipoproteins (HDLs) Intermediate-density lipoproteins (IDLs)
High-density lipoproteins (HDLs)
Absorbs excess cholesterol in the bloodstream and return it to the liver
High-density lipoproteins (HDLs) (AKA "Good Cholesterol")
Which response is coordinated by the heat-gain center? The vasomotor center increases blood flow to the dermis. In children, hypothalamic TRH release increases. Shivering decreases body temperature. Parasympathetic stimulation of the adrenal medullae releases epinephrine.
In children, hypothalamic TRH release increases.
Which statement regarding the citric acid cycle is true? Its function is to remove hydrogen atoms from organic molecules and transfer them to coenzymes. An acetyl group, CH3CO, from acetyl-CoA is attached to a six-carbon molecule. The citric acid cycle occurs in the cytoplasm. Cytochromes are the coenzymes that play a key role in the citric acid cycle.
Its function is to remove hydrogen atoms from organic molecules and transfer them to coenzymes.
Keith is concerned that his brain cells will not receive energy-rich nutrients without carbohydrates in his diet. Which of the following molecules is a product of lipid catabolism that his brain cells could use to create ATP? Triglycerides Ketone bodies Glycogen Amino acids
Ketone bodies
Which statement regarding long-term regulation of appetite is true? Ghrelin, which is secreted by the gastric mucosa, stimulates appetite. Several hormones of the digestive tract, including CCK, suppress appetite during the absorptive state. Leptin, a peptide hormone released by adipose tissues as they synthesize triglycerides, stimulates the satiety center. Neuropeptide Y, a hypothalamic neurotransmitter, stimulates the feeding center.
Leptin, a peptide hormone released by adipose tissues as they synthesize triglycerides, stimulates the satiety center.
Which of the statements below represents one potential disadvantage to Keith's proposed all-meat diet? Our bodies cannot use lipids as an energy source Lipid catabolism is slower than carbohydrate catabolism Lipids contain much less stored energy than carbohydrates Amino acids are preferred over lipids in aerobic metabolism
Lipid catabolism is slower than carbohydrate catabolism
Which characteristic correctly applies to lipid metabolism? Excess lipids can be stored as pyruvate. Triglyceride reserves are water-soluble droplets. Most lipids can be synthesized on demand. Stored lipids provide large amounts of ATP very quickly.
Most lipids can be synthesized on demand.
Which of the following is a response coordinated by the heat-loss center? The respiratory centers are stimulated. A gradual increase in muscle tone occurs. Hormones are released to increase the metabolic activity of all tissues. The vasomotor center is stimulated.
The respiratory centers are stimulated.
Which statement regarding amino acid metabolism is true? When broken down in the mitochondrion, the energy yield of an amino acid is negligible. Liver cells must break down amino acids into urea, a toxic compound. The body synthesizes all 10 essential amino acids. The removal of the amino group is the first step in amino acid catabolism.
The removal of the amino group is the first step in amino acid catabolism.
Which is a characteristic of oxidative phosphorylation? The stepwise passage of electrons by coenzymes embedded in the cristae of the mitochondrion releases energy. It occurs in the cytoplasm using a series of enzymatic reactions. It results in the production of pyruvate. The diffusion of potassium ions powers the production of ATP.
The stepwise passage of electrons by coenzymes embedded in the cristae of the mitochondrion releases energy.
What is a nutrient pool? a general term for vitamins and minerals together the metabolic reserves of the body as a whole an alternative term for a bolus of food in the digestive system an accessible source of substrates for a cell the region in the mitochondria where hydrogen atoms are removed from organic molecules
an accessible source of substrates for a cell
Choose the correct statement regarding glycolysis. There is a net gain of two ATP molecules for each glucose molecule. It is an aerobic process that breaks down a six-carbon glucose molecule into two three-carbon molecules of pyruvate. NAD accepts carbon atoms that can be transferred to mitochondria. It occurs in the mitochondrion.
There is a net gain of two ATP molecules for each glucose molecule.
synthesis of new organic molecules
anabolism
If Keith adopts an all-meat diet, with which vitamin below should he make sure to supplement his diet to avoid deficiency? Vitamin B7 Phosphorous Vitamin E Vitamin A
Vitamin A
Which nutrient group provides vitamins A, B12, pantothenic acid, thiamine, and riboflavin? fruits vegetables grains dairy
dairy
In the absorptive state of metabolic activity: insulin inhibits glucose uptake and glycogenesis. androgens, estrogens, and growth hormone stimulate protein synthesis. epinephrine is important in stimulating glycogenolysis in skeletal and cardiac muscle. glucocorticoids stimulate the mobilization of lipid and protein reserves.
androgens, estrogens, and growth hormone stimulate protein synthesis.
Chylomicrons: are lipoproteins-lipid-protein complexes that contain insoluble lipids. diffuse into the hepatic portal vein, after they are released from the intestinal cells by exocytosis. diffuse into blood capillaries. enter the bloodstream at the inferior vena cava.
are lipoproteins-lipid-protein complexes that contain insoluble lipids.
nucleic acid metabolism vitamin that comes from milk and meat. Effect of excess is polycythemia
b12
Which activity expends the greatest amount of energy per hour? speed walking climbing stairs competitive swimming jogging
competitive swimming
A(n) ________ contains all of the essential amino acids. essential fatty acid water-soluble vitamin carbohydrate complete protein fat-soluble vitamin
complete protein
Direct transfer of energy through physical contact
conduction
Which primary mechanism of heat transfer is the direct transfer of energy through physical contact? convection conduction radiation evaporation
conduction
Poisons like cyanide bind to ________ and prevent electron transfer. mitochondria enzymes cytochromes the endoplasmic reticulum acetyl-CoA
cytochromes
Which process describes the synthesis of glucose from noncarbohydrate sources? glycogenesis glycogenolysis glycolysis gluconeogenesis
gluconeogenesis
Although other nutrients can feed into the citric acid cycle, ________ yields energy the quickest. fat protein glucose glycogen All of the answers yield energy at the same rate.
glucose
glucose is converted to 2 pyruvate molecules in
glycolysis (produces 2 ATP for every glucose molecule)
Which condition results when body fluids become saturated with uric acid? phenylketonuria ketoacidosis gout kwashiorkor
gout
Part A Part complete Illustration showing TCA cycle with most intermediates and products left blank for labeling. Included on the image are Acetyl-CoA and the products that migrate to the Electron Transport System. Figure 23-1 Identify the substance labeled "4." NADH 4-carbon molecule FADH2 citric acid hydrogen atom
hydrogen atom
part of the brain that adjust heat loss and heat gain
hypothalamus
The area of the brain that regulates body temperature is the cerebral cortex. hypothalamus. pons. medulla oblongata. pineal gland.
hypothalamus.
Glucose: is absorbed and converted to pyruvate as needed by the liver. leaves the cytosol of the epithelial cells and reaches the interstitial fluid by simple diffusion. is generally used for catabolism after protein and lipid sources are used. is transported to the liver by way of the hepatic portal vein.
is transported to the liver by way of the hepatic portal vein.
All of the following are true of beta-oxidation except that it occurs in the mitochondria. it ultimately yields large amounts of ATP. it requires coenzyme A, NAD, and FAD. lipids are converted into glycogen molecules. fatty acids break down into acetyl-CoA that enter the citric acid cycle.
lipids are converted into glycogen molecules.
In the process of digestion, most nutrient absorption takes place in the duodenum. stomach. large intestine. small intestine. liver.
small intestine.
required for normal bone growth, intestinal calcium and phosphorus absorption
vitamin D
Cannot be synthesized; must be obtained from diet
Essential fatty acids
The breakdown of organic substrates in body
catabolism
Cells perform catabolism to generate ATP, which can be used for all of the following except diffusion. glycogen synthesis. muscle contraction. ion transport. protein synthesis.
diffusion
Fatty acids that are necessary for proper health but cannot be synthesized by the body are called essential fatty acids. low-density lipoproteins. water-soluble vitamins. high-density lipoproteins. chylomicrons.
essential fatty acids.
The sum of all of the biochemical processes going on within the human body at any given time is called metabolism. anabolism. catabolism. oxidative phosphorylation. glycolysis.
metabolism
The function of the citric acid cycle is to produce carbon dioxide. produce water. remove hydrogen atoms from organic molecules and transfer them to coenzymes. hydrolyze glucose. transfer the acetyl group.
remove hydrogen atoms from organic molecules and transfer them to coenzymes.
The vitamin that is part of coenzymes in glycolysis and the citric acid cycle is cobalamin. folic acid (folate). thiamine. riboflavin. niacin.
riboflavin