Cell Membranes and Microscopic Structures

These flashcards cover terminology related to cell membranes, their structure, function, and properties as discussed in the lecture.

Cell Membrane

A structure that defines the space of all cells and separates the internal cellular environment from the external environment.

Phospholipid Bilayer

Structure consisting of two layers of phospholipids where polar heads face outward and hydrophobic tails face inward, forming a semi-permeable membrane.

Prokaryotic Cells

Cells that do not have a membrane-bound nucleus or organelles. They possess a plasma membrane.

Eukaryotic Cells

Cells that have a nucleus and membrane-bound organelles, including the cell membrane.

Cytoplasm

The non-nuclear components within a cell, including the fluid and organelles, excluding the nucleus.

Cytosol

The fluid portion of the cytoplasm, primarily composed of water.

Fluid Mosaic Model

A model describing the structure of cell membranes, emphasizing that they are fluid and composed of a mixture of various components.

Amphipathic

Molecules that have both hydrophilic (water-loving) and hydrophobic (water-fearing) parts.

Cholesterol

A type of lipid that is an integral part of cell membranes, affecting membrane fluidity and stability.

Glycoproteins

Proteins that have carbohydrate chains attached, often involved in cell recognition.

Glycolipids

Lipids that have carbohydrate chains attached, found on the surface of membranes.

Transport Proteins

Proteins embedded in cell membranes that facilitate the movement of substances across the membrane.

Osmosis

The diffusion of water across a selectively permeable membrane.

Hydrophobic

Molecules or portions of molecules that do not interact favorably with water.

Hydrophilic

Molecules or portions of molecules that interact favorably with water.

Membrane Proteins

Proteins that are integral or peripheral to cell membranes, responsible for a variety of functions including transport, signaling, and cell recognition.

Semi-permeable

Property of cell membranes that allows certain molecules to pass through while restricting others.