Homeostasis
This buffering minimizes changes in blood pH as CO2 is loaded in the tissues and released in the lungs, linking CO2/O2 transport to acid-base homeostasis
What our notes say
- This buffering minimizes changes in blood pH as CO2 is loaded in the tissues and released in the lungs, linking CO2/O2 transport to acid-base homeostasis (Chemical path 2021 — Past Paper Questions & Answers)
- The parathyroid glands secrete parathyroid hormone (PTH), which is the primary regulator of calcium and phosphate homeostasis. (ENDOCRINE PATHOLOGY)
- Cellular processes have little relevance to the overall whole-body homeostasis (cat 2 2014 — Source Paper Awaiting Edit)
- Organ systems usually control one or more variables that contribute to the whole body homeostasis (cat 2 2014 — Source Paper Awaiting Edit)
- Explain the possible cause of this hypocalcaemia, and outline the changes in calcium homeostasis which have lowered calcium levels. (20 marks) (hsd sept21 clin chem saqs essay and case studies papers final exam papers — Past)
- • Homeostasis= maintenance of the internal environment within a narrow physiological set of parameters (Medical Physiology Assorted SAQs — With Answers (Past Paper Study Guide))
Study material on Homeostasis
- Calcium Homeostasis and Disorders
- LECTURE 6: Pancreatic and Adrenal Hormones
- cat 2 2014 — Source Paper Awaiting Edit
- Medical Physiology II (Paper 2)
- Renal Anatomy and Physiology
- Medical Physiology Section A - Complete Questions and Comprehensive Answers
- Medical Physiology Paper II MCQs
- LECTURE 4: Thyroid Hormones
- Calcium Homeostasis and Disorders
- Weekly Year 1: Physiology Exam - August 7, 2026 (Section A: MCQs)
- Medical Physiology CAT 2 — 2014 (Past Paper)
Practice questions on Homeostasis
In processes contributing to body homeostasis:
- Only negative feedback mechanisms are involved.
- Positive feedback is always detrimental.
- The internal environment is maintained within a narrow range of normal values.
- The body passively adapts to all external changes.
Answer: C. Homeostasis is the dynamic process of maintaining a stable internal environment within physiological limits, often through various feedback mechanisms. While negative feedback is dominant for stability, positive feedback has specific roles (e.g., childbirth). The internal environment is a dynamic range, not a fixed state, and the body actively regulates it.
Homeostasis:
- Is the process of maintaining a stable internal environment.
- Is solely controlled by the endocrine system.
- Always involves a single feedback loop.
- Leads to a state of equilibrium that is unchanging.
Answer: A. Homeostasis is the fundamental principle of maintaining a stable internal environment despite external fluctuations. It involves complex regulatory mechanisms from multiple organ systems, often utilizing feedback loops, and is a dynamic state of balance, not a static one.
Why doesn't muscle glycogen contribute significantly to blood glucose homeostasis during starvation? ---
- Muscle lacks glucose-6-phosphatase
- Muscle lacks phosphorylase
- Muscle stores little glycogen
- Muscle has non-branched glycogen
- Glycogen synthase is insensitive to G6P
Answer: A.
In processes contributing to body homeostasis ---
- Cellular processes have little relevance to the overall whole body homeostasis
- Organ systems usually control one or more variables that contribute to the whole body homeostasis.
- Body temperature control is under feedback control only.
- Body pH control is an example of intracellular control only
- Height is under adaptive control
Answer: A.
Homeostasis ---
- Refers to the static and absolutely constant state of life processes.
- Refers to the maintenance of physiological parameters within physiological limits.
- Homeokinesis and Homeodynamism are unrelated terms.
- Occurs at cellular level only.
- Implies that control mechanisms are not necessary
Answer: A.
Which of the following statements regarding the regulation of calcium homeostasis is TRUE? ---
- PTH secretion increases in response to elevated plasma calcium levels
- Calcitonin promotes calcium reabsorption from the kidneys to raise plasma calcium
- Vitamin D enhances intestinal absorption of calcium by increasing expression of calcium-binding proteins
- FGF23 increases plasma calcium by stimulating osteoclast activity
Answer: C.