General Principles of Physiology Practice Exam 2025 – Complete Test Prep

The rate of glomerular filtration, which is the process by which the kidneys filter blood to form urine, can indeed be influenced by various physiological factors, making the choice of all factors being relevant appropriate.

Blood osmolarity impacts glomerular filtration because it reflects the concentration of solutes in the blood. If blood osmolarity is high, indicating dehydration or other conditions, the kidneys will adjust by conserving water, which can reduce glomerular filtration rate (GFR). Conversely, low blood osmolarity situations prompt the kidneys to filter more to help balance fluid and solute levels.

Muscle mass relates to GFR as well, mainly through its association with metabolic activity and the production of substances like creatinine. Individuals with greater muscle mass tend to have higher baseline levels of certain metabolites that can influence how well the kidneys filter blood.

Hormonal changes, such as the actions of hormones like renin, angiotensin, and aldosterone, also play a vital role in regulating renal blood flow and, consequently, the rate of glomerular filtration. These hormones help manage blood pressure and fluid balance, which are crucial for maintaining optimal filtration rates.

Considering all these factors together emphasizes the complex interplay in the regulation of glomerular filtration.