In cold conditions, how does blood flow change to restrict heat loss?
Heat transfer from warm blood in arteries warms cooler venous blood
What is the electron transport system's role in the generation of ATP?
It creates a steep concentration gradient across the inner mitochondrial membrane
Why are effects of diet more profound and immediate in infants compared with adults?
Infants' energy sources and mineral reserves are smaller
Which of the following is not one of the processes essential to stabilizing body fluid volumes, solute concentration, or pH of the ECF?
Hormone balance
Which vitamins is your body capable of synthesizing?
Vitamins D and K
If the osmotic concentration of ECF increases, which of the following happens?
Water moves from cells into ECF
What effect would being in the desert without water for a day have on plasma osmotic concentration?
Increase of osmotic concentration
What effect does drinking a pitcher of distilled water have on ADH secretion?
Secretion of ADH decreases
Mr. Proctor has high blood pressure. As his physician, why do you counsel him to limit his intake of sodium?
Sodium causes an increase in blood volume and blood pressure, and decreased ADH secretion
Which is more dangerous, disturbance of sodium balance or disturbances of potassium balance?
Disturbances of potassium balance
What is the primary cause of hypercalcemia?
hyperparathyriodism
Why do homeostatic mechanisms that adjust composition of body fluids respond to changes in the ECF, rather than ICF?
A change in one ECF component rapidly affects all body cells
Which hormone affecting fluid and electrolyte balance is responsible for determining the rate of Na+ absorption and K+ loss along the DCT?
Aldosterone
Which of the following is true concerning metabolic generation of water?
Breaking down 1g of lipid generates more water than breaking down 1g of carbohydrate
Which of the following characteristics distinguished a strong acid from a weak acid?
Strong acids dissociate completely in solution
Which of the following is not one of the three major buffer systems?
Potassium buffer system
What is the effect of acidosis on the circulatory system?
Peripheral vasodilation and drop in BP
Mrs. Adams has diabetes mellitus, but rarely eats her "diabetic friendly" meals. What condition may result from her poor eating behavior?
Ketoacidosis
Why can prolonged vomiting produce metabolic alkalosis while diarrhea produces metabolic acidosis?
diarrhea causes loss of HCO3- in the ECF/vomiting causes increase of HCO3- in the ECF
What change in an elderly person's body contributes to poor acid-base balance?
Reduction in GFR and reduction in number of functional nephrons
What factor contributes to the relatively higher water content of adult males compared to adult females?
Males have higher average muscle mass
Why does the amount of urea in blood increase during the post-absorptive state?
protein digestion creates urea
in which region(s) of the digestive tract does mechanical processing occur?
all of the above
Which disorder increase the rate at which fluids move into the peritoneal cavity? What condition results from the excess fluids in the peritoneal cavity?
Liver disease/ascites
What is the importance of the mesenteries?
All of the above are correct
The four major layers of the GI tract are ____.
Mucosa, submucosa, muscularis externa, and serosa
Where are the motor neurons that control smooth muscle contraction and glandular secretions of the GI tract located?
In the myenteric plexus
What process in the liver increases after you have eaten a high-carbohydrate meal?
glycogenesis
Wayne's cardiac muscle cells have been releasing ANP in response to overstretching of his heart walls. What is the effect of the release of ANP?
ANP blocks the release of ADH and aldosterone
What consequence(s) is/are the result of a dietary deficiency of one or more essential amino acids?
A and C are correct
If a cell accumulates more acetyl-CoA than it can metabolize by way of the TCA cycle, which of the following products will form?
Ketone bodies
Why does prolonged sweating increase plasma sodium ion levels?
Sweating causes a greater loss of water than sodium
Which type of epithelium lines the oral cavity? Why?
Stratified squamous epithelium/area id subject to abrasion
Why are proteins an impractical source of quick energy, a "last ditch" source of energy?
All of the above
The parotid glands secrete ____, which contain large amounts of ___.
Serous secretions/salivary amylase
Your molars are most useful for ___.
crushing and grinding a tough pizza crust
Where in the human body is the fauces?
between the oral cavity and the pharynx
How do the roles of pepsinogen and HCl interact in the stomach?
HCl is necessary for the conversion of pepsinogen to pepsin
When a person suffers from chronic gastric ulcers, the branches of the vagus nerve serving the stomach are sometimes surgically severed. Why?
the vagus nerve stimulated gastric secretions
Which of the following is/are true of the hemoglobin buffer system?
A and B are correct
What effect does a decrease in the pH of body fluids have on respiratory rate?
Respiratory rate increases
During an asthma attack, Kristen's bronchioles constrict, reducing pulmonary exchange. Which of the following scenarios will result?
Increased breathing rate, decreased plasma pH and hypercapnia
How does a prolonged fast affect the body's pH?
pH decreased after a fast
What is the primary source of flatus emitted from the intestines?
Indigestible carbohydrates acted on by bacteria
Why is oxidative phosphorylation the most important mechanism for generating ATP?
it produces more than 90% of ATP used by the body cells
NADH produced by glycolysis in skeletal muscle fibers leads to production of two ATP molecules in mitochondria, but NADH produced by glycolysis in cardiac muscle cells leads to production of three ATP molecules. Why?
Different intermediaries
How does a decrease in the level of cytoplasmic NAD affect ATP production in mitochondria?
ATP production decreases
What is the process of gluconeogenesis?
the formation of glucose from precursors such as lactic acid
Why are high-density lipoproteins (HDLs) considered beneficial?
they reduce fat and cholesterol in the bloodstream
Which structures comprise a heptic triad?
Branches of the heptic portal vein and heptic artery, and a branch of the bile duct
How do most chylomicrons enter the lymphatic system?
through lacteals
How does taking fat-soluble vitamins on an empty stomach affect the absorption of those vitamins?
The vitamins are not absorbed, because they require presence of other lipids
Why is diarrhea potentially life threatening, but constipation is not?
diarrhea causes rapid water and electrolyte loss
Why do athletes in training try to maintain a positive nitrogen balance?
The actively synthesize N compounds, so must absorb more than they secrete
Which age-related changes in the digestive system are the results of decreased smooth muscle tone?
A and C are correct
Examples of catabolism include all of the following except ___.
Synthesis of new organic molecules
how do the regional specializations of the small intestine change along its length?
All of the above are correct
What effect(s) does the secretion of CCK have on a fatty meal's entrance to the duodenum?
inhibits secretion of gastric acids and enzymes, slowing gastric emptying
What effect does secretion of secretin by enteroendocrine cells of the duodenum have on the pancreas?
It stimulates production of pancreatic buffers that protect the duodenum
Why is lipid digestion more impaired by damage to the exocrine pancreas than is carbohydrate or protein digestion?
All of the above
What is the primary role of the TCA cycle in the production of ATP?
transfer electrons from substrates to coenzymes
What characteristic of lipoproteins allows them to be made water-soluble?
they have superficial coating of phospholipids and proteins
Why are LDLs considered "bad cholesterol"?
B and C are correct
What happens during the process of trasamination?
A keto acid is converted into an amino acid that can leave the mitochondria
Why does a diet that is deficient in pyidoxine (vitamin B6) affect protein metabolism?
The first step in amino acid catabolism requires a coenzyme derivative of B6
Why does hypervitaminosis more commonly involve fat-soluble vitamins?
Excess fat-soluble vitamins are stored in body lipids
What is unusual about the muscularis externa of the esophagus?
it contains skeletal muscle along the superior one-third of its length
Which of the following are the primary ions present in ECF?
Na+, Cl-, HCO3-
how does a decrease in the amount of bile salts in the bile affect the amount of vitamin A in the body?
It would decrease vitamin A
Why is the catabolism of dietary carbohydrates and proteins considered "not as productive" as catabolism of lipids?
Lipids release almost twice the energy of proteins or carbohydrates