Body Fluids and Cell Membrane Transport Quiz

The average diameter of non-gated channels in the cell membrane is 5 angstroms. This is a very small size, reflecting the selective nature of these channels.

Facilitated diffusion is a type of passive transport where molecules move across the cell membrane with the help of transport proteins, but without requiring energy. This movement follows the concentration gradient.

Sodium has the highest concentration in plasma, which makes it a major contributor to the osmotic pressure of blood.

Inorganic ions, which are charged particles, can easily pass through the lipid bilayer of the cell membrane. This is because the lipid bilayer is hydrophobic, repelling charged molecules.

Active transport is the movement of molecules across the cell membrane against their concentration gradient. This process requires energy input from the cell.

Intravascular fluid, or blood plasma, is the fluid within blood vessels. It accounts for 5% of body weight.

Interstitial fluid is the fluid that surrounds cells. It is often referred to as the 'internal environment' of the body, as it provides the medium for cells to exchange nutrients and waste products.

Intracellular fluid is the fluid inside cells. It makes up the largest fraction of body water and accounts for 40% of body weight.

Extracellular fluid is the fluid outside of cells. It includes both intravascular and interstitial fluids, and accounts for 20% of body weight.

Total body water refers to the total amount of water in the body. It accounts for 60% of body weight.