how do organisms maintain homeostasis

ATI TEAS 7

ATI TEAS Science

1. How do organisms maintain homeostasis?

A. By increasing their body temperature, blood pH, and fluid balance.
B. By undergoing biochemical processes and absorbing energy to increase entropy.
C. By undergoing biochemical processes to maintain the order of their external environment.
D. By using free energy and matter via biochemical processes to work against entropy.

Correct answer: D

Rationale: Organisms maintain homeostasis by utilizing free energy and matter through biochemical processes to counteract entropy, which helps in preserving internal stability. This process involves maintaining a balance within the organism's internal environment despite external changes, ensuring proper functioning and survival. Choice A is incorrect because increasing body temperature, blood pH, and fluid balance alone do not define the comprehensive process of maintaining homeostasis. Choice B is incorrect as absorbing energy to increase entropy goes against the concept of maintaining internal stability. Choice C is incorrect as maintaining the order of the external environment does not directly contribute to the organism's internal stability and balance.

2. What is the largest bone in the human body?

A. Femur (thigh bone)
B. Tibia (shin bone)
C. Humerus (upper arm bone)
D. Scapula (shoulder blade)

Correct answer: A

Rationale: The femur, also known as the thigh bone, holds the title of the largest bone in the human body. Situated in the upper leg, the femur plays a vital role in supporting the body's weight and enabling movement. While the tibia (shin bone), humerus (upper arm bone), and scapula (shoulder blade) are all essential bones, none of them match the femur in terms of size and importance. The tibia, humerus, and scapula are comparatively smaller bones with specific functions in their respective areas of the body, but they do not surpass the femur in size or significance.

3. Which of the following terms refers to the abnormal sound heard during a stethoscope examination, potentially indicating a heart valve issue?

A. Tachycardia
B. Bradycardia
C. Heart murmur
D. Arrhythmia

Correct answer: C

Rationale: A heart murmur is an abnormal sound heard during a stethoscope examination of the heart. It can indicate issues with the heart valves, such as stenosis or regurgitation. Tachycardia refers to a fast heart rate, bradycardia refers to a slow heart rate, and arrhythmia refers to an irregular heart rhythm. Therefore, the correct answer is 'Heart murmur,' as it specifically relates to the abnormal sound heard during a stethoscope examination that may signal a heart valve issue.

4. A spring with a spring constant of 100 N/m is stretched 0.2 m from its equilibrium position. What is the potential energy stored in the spring?

A. 2 J
B. 4 J
C. 8 J
D. 20 J

Correct answer: C

Rationale: The potential energy stored in a spring is given by the formula $PE = \frac{1}{2}kx^2$, where $k$ is the spring constant and $x$ is the displacement from the equilibrium position. Substituting the given values, we get $PE = \frac{1}{2} \times 100 \times (0.2)^2 = 8$ J.

5. Which of the following conditions is characterized by a wasting or decrease in muscle mass?

A. Hypertrophy
B. Atrophy
C. Spasticity
D. Myopathy

Correct answer: B

Rationale: Atrophy is the correct answer as it is characterized by a wasting or decrease in muscle mass. Hypertrophy, on the other hand, refers to an increase in muscle size. Spasticity is associated with increased muscle tone due to continuous contraction of muscles. Myopathy, on the other hand, is a broad term used to describe various muscle diseases affecting muscle tissue, which may or may not involve muscle wasting.