Fluid Compartments and Homeostasis

This set of flashcards covers key concepts related to body fluid compartments, osmolarity, and the mechanisms regulating homeostasis.

How do total body water (TBW) volumes compare between normal adult males and females?

Males generally have a higher total body water volume compared to females.

What are the relative volumes and osmolarities of intracellular fluid (ICF) compared to extracellular fluid (ECF)?

ICF has a larger volume compared to ECF, with a lower osmolarity in ICF relative to ECF.

How is extracellular fluid (ECF) subdivided, and what are the volume and composition differences between plasma and interstitial fluid (IF)?

ECF is subdivided into plasma and interstitial fluid; plasma has higher protein content, while IF has lower protein content and volumes differ.

What mechanisms separate different body fluid compartments?

Boundary walls include cell membranes and vascular walls; transport mechanisms include diffusion, osmosis, and active transport.

What are the normal routes of body water entry and loss, and how can changes in water intake/loss disrupt osmolarity homeostasis?

Entry through beverages/food, and loss via urine, sweat, and respiration; changes can lead to hyperosmolarity or hypo-osmolarity.

What occurs to body fluid volume and osmolarity when a person drinks a large volume of pure water?

Fluid volume increases and osmolarity decreases, prompting compensatory mechanisms to restore balance.

What happens to blood pressure when blood volume decreases significantly due to dehydration or hemorrhage?

Blood pressure decreases significantly due to reduced blood volume.

How do body osmolarity changes differ in dehydration versus hemorrhage?

Osmolarity typically increases in dehydration and may remain unchanged or vary in hemorrhage, depending on fluid loss.

How do the cardiovascular, endocrine, and urinary systems monitor blood volume and/or blood pressure?

They use baroreceptors and chemoreceptors to sense changes in blood volume and pressure.

What integrated responses do the cardiovascular, endocrine, and urinary systems enact in response to low blood pressure from dehydration?

They increase heart rate, release hormones like aldosterone and ADH, and decrease urine output.

What is the normal pH range for arterial blood?

The normal pH range for arterial blood is 7.35 to 7.45.

How do changes in pH outside the normal range affect body functions?

Altered pH can disrupt enzyme functions, affect oxygen transport, and impair cellular processes.

What are the normal ranges for arterial blood PCO2 and HCO3 - ?

Normal arterial blood PCO2 is 35-45 mmHg and HCO3 - 22-26 mEq/L.

What are the major buffer systems of the body, and where are they located?

Major buffer systems include bicarbonate and protein buffer systems, located primarily in extracellular fluid.

How does the transport of carbon dioxide in blood relate to the bicarbonate buffer system?

CO2 transport affects pH; as CO2 increases, it leads to an increase in H+ via the bicarbonate buffer system, leading to a decrease in pH.