Cell Physiology Lecture 1

These flashcards cover key concepts and definitions related to cell physiology, including body compartments, homeostasis, cell membrane functions, and intercellular communications.

What is Physiology?

The study of normal functions of living organisms and how these functions are performed and integrated.

What are the two types of body compartments?

Intracellular and Extracellular compartments.

What fraction of total body water is intracellular fluid (ICF)?

2/3 or 40% of the total body weight.

What is Homeostasis?

The body's effort to maintain a constant internal environment.

What is the total body water (TBW) of a 70 kg young adult male?

42 liters, which is 60% of total body weight.

What are negative feedback mechanisms?

Mechanisms that drive factors of the internal environment in the opposite direction of external changes.

What role do proteins play in the cell membrane?

They act as adhesion molecules, enzymes, antigens, receptors, ion channels, carriers, and pumps.

Define Osmosis.

The passive movement of water from a low solute concentration area to a higher solute concentration area.

What is simple diffusion?

The passive movement of small molecules from higher to lower concentration through the lipid bilayer or protein channels.

What distinguishes facilitated diffusion from simple diffusion?

Facilitated diffusion involves the movement of larger molecules with the help of a carrier (protein channel).

What is active transport?

The active movement of specific ions from lower to higher concentration areas, requiring energy in the form of ATP.

What is neural communication?

The release of neurotransmitters at synaptic junctions from nerve cells that act across a narrow synaptic cleft on a postsynaptic cell.

What is paracrine communication?

The diffusion of cell products in the ECF that affect neighboring cells.

What is endocrine communication?

The process by which hormones and growth factors reach cells via circulating blood.

List the components of the cell membrane.

Mainly proteins, phospholipid bilayer, cholesterol, other lipids, and carbohydrates.

Mention 5 functions of cell membrane proteins.

1. Adhesion molecules 2. Enzymes 3. Antigens 4. Receptors 5. Ion channels.