ATI Anatomy and Physiology Online Practice

Correct Answer: C

Rationale: In negative feedback mechanisms, changes away from the normal state stimulate changes in the opposite direction. This is a fundamental concept in biological systems where the response to a stimulus opposes the initial change, helping to maintain homeostasis. Choice A is incorrect because negative feedback does not stimulate changes in the same direction. Choice B is incorrect because negative feedback does not inhibit all body reactions, but rather specific responses. Choice D is incorrect because negative feedback does not stimulate a reduction in all body requirements, but rather adjusts specific functions to restore balance.

Correct Answer: B

Rationale: Organelles are not exclusive to human cells but are present in various types of cells across different organisms. Option B is incorrect as it suggests that organelles are only found in human cells, which is false. Choices A, C, and D are correct statements about organelles. Organelles indeed carry out specific activities, are made up of aggregates of large molecules, and can be found in many types of cells.

Correct Answer: D

Rationale: The correct answer is 'sagittal.' A sagittal section divides the body into right and left portions. Choice A, 'frontal,' is incorrect as it divides the body into front and back portions. Choice B, 'transverse,' divides the body into upper and lower portions. Choice C, 'coronal,' divides the body into anterior and posterior portions. Therefore, 'sagittal' is the most appropriate term for a section separating the body into right and left portions.

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.

Correct Answer: B

Rationale: The correct answer is 'the age of her eggs.' As women age, the quality of their eggs decreases, leading to a higher risk of chromosomal abnormalities and infertility. This decline in egg quality is why advanced maternal age is associated with a higher risk of certain pregnancy complications. Choices A, C, and D are incorrect because the primary concern in this context is related to the age-related changes in a woman's eggs, not sperm, diabetes risk, or cholesterol levels.