Question 1

Refer to the flowchart in Image 1. If an organism experiences an external change that disrupts homeostasis, what is the next step in the process according to the diagram?

Accepted Answer

An internal change results in loss of homeostasis.

Question 2

Based on Image 2, what is the correct sequence of events in a physiological response loop?

Accepted Answer

Stimulus → Sensor → Input signal → Integrating center → Output signal → Target → Response

Question 3

Image 3 depicts a feedback loop during childbirth. Which type of feedback is illustrated, and what event ultimately stops the cycle?

Accepted Answer

Positive feedback; delivery of the baby

Question 4

According to the table in Image 4, which of the following statements is TRUE regarding the relationship between osmolarity and tonicity?

Accepted Answer

Hyposmotic solutions are always hypotonic.

Question 5

A patient is given 5% dextrose in water (D5W) intravenously. Based on Image 5, what are the osmolarity and tonicity of this solution?

Accepted Answer

Hyperosmotic and hypotonic

Question 6

Using the equation in Image 6, which of the following changes would NOT increase the rate of diffusion across a membrane?

Accepted Answer

Decreasing the surface area

Question 7

A solution is isosmotic to a cell but contains a high concentration of penetrating solutes. What will happen to the cell when placed in this solution?

Accepted Answer

The cell will swell because the solution is hypotonic.

Question 8

Which of the following best describes the role of the integrating center in a physiological control system, as described in Image 2?

Accepted Answer

It initiates the output signal after evaluating input from the sensor.

Question 9

In the positive feedback loop shown in Image 3, what is the effect of oxytocin release?

Accepted Answer

It stimulates further uterine contractions.

Question 10

A patient receives 0.45% saline intravenously. According to Image 5, what is the tonicity of this solution and what effect will it have on red blood cells?

Accepted Answer

Hypotonic; cells will swell

Question 11

If the compensation mechanisms described in Image 1 fail after a loss of homeostasis, what is the likely outcome?

Accepted Answer

The organism develops illness or disease.

Question 12

Which of the following best explains why osmolarity alone cannot predict the tonicity of a solution, as shown in Image 4?

Accepted Answer

Osmolarity does not account for the permeability of solutes across the cell membrane.

Question 13

Which of the following intravenous solutions would be most appropriate for treating a patient with severe dehydration, based on the information in Image 5?

Accepted Answer

0.9% saline (isotonic)

Question 14

According to the equation in Image 6, what would happen to the rate of diffusion if the membrane permeability is doubled while all other factors remain constant?

Accepted Answer

The rate of diffusion would double.

Question 15

Which of the following best describes the difference between negative and positive feedback loops, as illustrated in Images 1 and 3?

Accepted Answer

Negative feedback opposes the original stimulus, while positive feedback amplifies it.

Mini-Textbook Study Notes: Foundations of Human Physiology

Study Guide - Practice Questions

Study Guide - Flashcards