the recent discovery of taste receptors that detect sweetness in the small intestine illustrates that

ATI RN

ATI Anatomy and Physiology Online Practice

1. The recent discovery of taste receptors that detect sweetness in the small intestine illustrates that

A. chemical responses occur in various parts of the body.
B. new discoveries about anatomy and physiology are still being made.
C. everything about anatomy and physiology has been discovered.
D. the molecular and cellular level is crucial in anatomy and physiology.

Correct answer: B

Rationale: The recent discovery of taste receptors in the small intestine illustrates that new discoveries about anatomy and physiology are still being made. This finding demonstrates that our understanding of the human body is continuously evolving. Choice A is incorrect because the discovery does not imply that chemical responses occur in only one part of the body but rather showcases a specific new discovery. Choice C is incorrect as it is highly improbable that everything about anatomy and physiology has been discovered given the complexity of the human body. Choice D is incorrect as while the molecular and cellular level is important in anatomy and physiology, the primary focus of this discovery is on the new findings about the taste receptors in the small intestine.

2. Which of the following illustrates a positive feedback mechanism?

A. Maintaining blood pressure
B. Uterine contractions during childbirth
C. Body temperature control
D. Control of blood sugar

Correct answer: B

Rationale: The correct answer is uterine contractions during childbirth. This is an example of a positive feedback mechanism where the initial stimulus (contractions) leads to an increase in intensity and frequency, ultimately resulting in childbirth. In contrast, choices A, C, and D (maintaining blood pressure, body temperature control, and control of blood sugar) are examples of negative feedback mechanisms. These mechanisms work to maintain stability by counteracting any deviations from the set point, rather than amplifying the response like in a positive feedback mechanism.

3. In a normally functioning cardiovascular system, where does the heartbeat originate?

A. Atrioventricular nodes
B. Bundle of His
C. Purkinje fibers
D. Sinoatrial node

Correct answer: D

Rationale: The correct answer is the Sinoatrial (SA) node. The SA node is known as the natural pacemaker of the heart as it initiates the electrical impulses responsible for the heartbeat. The other choices, such as the Atrioventricular (AV) nodes, Bundle of His, and Purkinje fibers, are involved in conducting the electrical signals generated by the SA node to coordinate the heart's contractions. Therefore, they do not serve as the primary origin of the heartbeat.

4. Blood cells are produced in the organs of the _______ system.

A. endocrine
B. skeletal
C. superior to
D. inferior to

Correct answer: C

Rationale: Blood cells are produced in the organs of the hematopoietic system. The correct answer is 'superior to' as this refers to the location of the organs responsible for blood cell production, typically bone marrow found in bones such as the vertebrae, ribs, and skull. 'Endocrine' (Choice A) refers to a different system responsible for hormone production. 'Skeletal' (Choice B) relates to bones but not specifically to the production of blood cells. Choices C and D, 'superior to' and 'inferior to,' do not make sense in the context of blood cell production and are incorrect.

5. Do chromosomes get longer as a cell ages?

A. TRUE
B. FALSE
C. Not Sure
D. None of the above

Correct answer: B

Rationale: Chromosomes do not get longer as a cell ages. In fact, chromosomes condense and become more compact during cell division to ensure proper segregation. Choice A is incorrect because chromosomes do not elongate with age. Choice C is not the correct answer as there is scientific evidence to support that chromosomes do not lengthen over time. Choice D is not the right option as the correct answer is 'False' in this case.