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. A guitar string vibrates at a fundamental frequency of 440 Hz. What is the frequency of the second harmonic (first overtone)?

A. 220 Hz
B. 440 Hz
C. 880 Hz
D. 1760 Hz

Correct answer: C

Rationale: The second harmonic (first overtone) is twice the frequency of the fundamental frequency. Therefore, the frequency of the second harmonic is 440 Hz * 2 = 880 Hz. The second harmonic has a frequency that is one octave higher than the fundamental frequency, representing the first overtone of the vibrating string. Choice A (220 Hz) is incorrect as it represents half the fundamental frequency and is the second harmonic, not the first overtone. Choice B (440 Hz) is the fundamental frequency itself. Choice D (1760 Hz) is the frequency of the fourth harmonic, not the second harmonic.

3. Which of the following water-soluble vitamins is NOT synthesized in the large intestine?

A. B6
B. Biotin
C. Pantothenic acid (Vitamin B5)
D. Vitamin K

Correct answer: A

Rationale: The correct answer is A: B6. Vitamin B6 is not synthesized in the large intestine, while biotin, pantothenic acid (Vitamin B5), and Vitamin K can be synthesized by gut microflora. Biotin, B5, and K are examples of water-soluble vitamins that can be produced in the large intestine, but B6 needs to be obtained through dietary sources. Therefore, B6 is the correct answer as it is not synthesized within the large intestine, unlike the other options.

4. During REM sleep, which type of brain wave activity is often seen and associated with dreaming?

A. Delta waves
B. Alpha waves
C. Beta waves
D. Theta waves

Correct answer: D

Rationale: Theta waves are the correct answer as they are often seen during REM (rapid eye movement) sleep, the stage of sleep closely related to dreaming. Theta waves have a frequency of 4-7 Hz and are typically present during deep relaxation, meditation, and light sleep stages. Delta waves (choice A) are associated with deep sleep stages, not REM sleep. Alpha waves (choice B) are present during wakefulness and relaxation but not predominantly during REM sleep. Beta waves (choice C) are associated with alertness, problem-solving, and active thinking, not specifically with REM sleep or dreaming.

5. What is the temperature of 35°C in Kelvin?

A. 220
B. 238
C. 308
D. 345

Correct answer: C

Rationale: To convert Celsius to Kelvin, add 273.15 to the Celsius temperature. In this case, 35°C + 273.15 = 308.15 K. Therefore, the correct answer is 308 K. Choice A (220) is incorrect as it does not account for adding 273.15 to convert to Kelvin. Choice B (238) is incorrect as it is not the result of adding 273.15 to 35°C. Choice D (345) is incorrect as it is not the correct conversion of 35°C to Kelvin.