Question 1

Blake is studying for a quiz and writes in his notes that the extracellular fluid in his body would include

Accepted Answer

Extracellular fluid is the fluid that surrounds and bathes the cells in the body. It includes the blood supply, cerebrospinal fluid, and interstitial fluid, but not the fluid contained within the body cells (intracellular fluid). Therefore, option B is the correct choice.

Question 2

Ronnie is most likely experiencing osmotic thirst because of

Accepted Answer

Osmotic thirst is triggered by cellular dehydration. When there is a decrease in the concentration of water inside the body's cells, osmoreceptors in the hypothalamus are activated, leading to the sensation of thirst. This is likely what Ronnie is experiencing.

Question 3

Floria is most likely experiencing hypovolemic thirst because of

Accepted Answer

Hypovolemic thirst is caused by a decrease in blood volume, which can occur due to factors such as sweating, vomiting, diarrhea or blood loss. This triggers thirst sensations as the body tries to replenish lost fluids. Options A, C and D are not related to hypovolemic thirst.

Question 4

An emergency room (ER) staff has been alerted by an ambulance of the imminent arrival of a patient who nearly drowned at a nearby beach. The ER staff should expect that the patient will have inhaled a large amount of seawater, and consequently will need to treat the patient for the effects of highly

Accepted Answer

Seawater is hypertonic, meaning it has a higher concentration of solutes than the patient's extracellular fluid. When the patient inhales seawater, the hypertonic seawater will draw water out of the patient's cells, leading to dehydration. ER staff should treat the patient for the effects of hypertonic extracellular fluid, including possible cell dehydration.

Question 5

The human blood supply makes up about _________ percent of the body's total fluids.

Accepted Answer

The human blood supply makes up approximately 7% of the body's total fluids.

Question 6

Most excess sodium and water in the body are excreted by

Accepted Answer

The kidneys play a major role in filtering excess sodium and water from the body through urine. Perspiration and respiration do contribute to some extent in excreting sodium and water, but not as significantly as the kidneys. The intestines primarily play a role in absorbing nutrients and water from food, rather than excreting sodium and water from the body.

Question 7

The "rule" that says humans should drink eight cups of plain water per day is

Accepted Answer

While humans do need to consume fluids in addition to what they get from their foods, the "rule" of eight cups of plain water per day is not necessary because we actually take in about half of the fluids we need from the foods we eat. Therefore, eight cups of water on top of our food intake would be unnecessary for most people.

Question 8

(see Figure 9.6)
Bernice is studying for a quiz. She writes in her notes that the structure labeled #1 is called the

Accepted Answer

The structure labeled #1 is the POA (preoptic area) of the hypothalamus, which is responsible for regulating body temperature and controlling the release of hormones that contribute to eating and drinking behaviors. The posterior hypothalamus (#2) is responsible for controlling arousal and promoting wakefulness, while the septal area (#3) is involved in pleasure and reward sensations. The pituitary gland (#4) is a separate structure that is responsible for releasing hormones that regulate various bodily functions.

Question 9

Electrolytes are

Accepted Answer

Electrolytes are substances that have broken up into ions in a solution, meaning they can conduct electricity. They can be positively or negatively charged solutes. B is incorrect because solutes that do not carry an electrical charge are non-electrolytes. C and D are incorrect because electrolytes can be either positively or negatively charged.

Question 10

Humans need to ingest

Accepted Answer

The recommended daily intake of fluid for an adult is about 2.5 liters (about 0.55 gallons) per day. This amount can vary based on age, gender, activity level, and other factors, but generally, humans need to ingest this much fluid to maintain proper hydration and promote healthy bodily functions. Option A is incorrect because humans need to consume fluids in addition to those contained in food. Option B is too low and may not be sufficient for proper hydration, and option C is also lower than the recommended amount.

Question 11

Pyrogens influence fever by which of the following mechanisms of action?

Accepted Answer

Pyrogens cause fever by reducing the activity of warm-sensitive neurons in the hypothalamus, leading to an increase in the body's set-point temperature.

Question 12

Intracellular fluid makes up about _________ of the body's total fluids.

Accepted Answer

Intracellular fluid (ICF) is the fluid inside cells, while extracellular fluid (ECF) is the fluid outside cells but within the body. ICF makes up about two-thirds of the body's total fluids, while ECF makes up the remaining one-third.

Question 13

Tennie is in her physiology lab and is working on a lab project. Her teacher hands out a syringe filled with an isotonic solution. The solution has

Accepted Answer

An isotonic solution has the same concentration of solutes as normal body fluids. This means that there is no net movement of water in or out of the cells, making it a good solution for physiological experiments or medical treatments.

Question 14

Stuart was in a serious automobile accident and, in addition to breaking several bones, he suffered a deep cut that was bleeding badly. As he waited for help to arrive, it is likely that Stuart was beginning to experience

Accepted Answer

Stuart is likely experiencing hypovolemic thirst due to the bleeding from his deep cut. This type of thirst is triggered by a decrease in blood volume and can lead to dehydration if not addressed. Hyponatremia, a condition in which there is an imbalance of electrolytes in the blood, is not likely to occur in this situation. Similarly, strong osmotic thirst, which is triggered by a high concentration of solutes in the blood, is not likely to be present as Stuart's blood is likely diluted due to the bleeding.

Question 15

Simona is in the laboratory and is working with a solution that has a lower level of solutes than human blood. Relative to blood, her solution would be

Accepted Answer

A solution that has a lower level of solutes compared to another solution is called hypotonic. In this case, Simona's solution has a lower level of solutes than human blood. Therefore, her solution would be hypotonic in comparison to blood.

Question 16

Kimberlie's core temperature has increased. As a result,

Accepted Answer

Warm-sensitive neurons in the preoptic area (POA) of the hypothalamus inhibit cold-sensitive neurons when the core temperature increases, while temperature-insensitive neurons remain unaffected by changes in temperature.

Question 17

In osmosis

Accepted Answer

Osmosis is the process where water moves across a semipermeable membrane from an area of low solute concentration to an area of high solute concentration to equalize the solute concentrations on both sides of the membrane.

Question 18

In addition to receiving input from thermoreceptors in the skin and spinal cord, warm-sensitive cells in the preoptic area (POA) of the hypothalamus

Accepted Answer

The warm-sensitive cells in the POA have receptors that can sense temperature changes in their vicinity. This allows them to detect changes in the overall temperature of the body and initiate appropriate responses to maintain homeostasis. The POA also receives input from other parts of the brain, such as the cerebral cortex, that can influence its activity based on higher-order cognitive processes.

Question 19

Nathan is drinking a sports drink filled with electrolytes. Compared to water, his drink is

Accepted Answer

A sports drink filled with electrolytes is hypertonic compared to water because it contains a higher concentration of solutes (electrolytes) than the fluid inside the body's cells. This can lead to water moving out of the cells to balance the concentration, which is why it's considered hypertonic.

Question 20

Which of the following factors contributes the least to feelings of thirst?

Accepted Answer

While a dry mouth can contribute to feelings of thirst, it is not the primary factor. The reduction in intracellular and extracellular fluid levels, as well as an increase in the concentration of extracellular solutes, signal the body to increase fluid intake to maintain proper hydration levels.

Quiz 9: Homeostasis, Motivation, and Reward