Cellular Communication, Tissue Types, Fluid Compartments, and Membrane Structure

Vocabulary flashcards generated from lecture notes covering intercellular communication, primary cell and tissue types, functional units, ECM, fluid compartments, chemical bonding properties, and plasma membrane structure.

Extracellular signal

A chemical signal, or chemical messenger, used for communication between cells.

Paracrine

A chemical signal released by a cell that affects nearby cells by traveling through interstitial fluid.

Autocrine

A special case of cell signaling in which a cell communicates with itself.

Neurotransmitter

A chemical signal released only by neurons that acts on an adjoining cell via interstitial fluid.

Endocrine communication

A chemical signal released by a gland or neuron that travels through the blood to affect distant cells.

Neurohormone

An endocrine signal or hormone released specifically by a neuron.

Genome

The cell's DNA or genetic information.

Proteome

The collection of proteins associated with a cell, which determines its specific functions.

Lipidome

The collection of lipids or fats associated with a cell.

Cell differentiation

The process, also called specialization, by which cells become specialized for different functions.

Epithelial cells

A primary cell type responsible for creating an inside and outside boundary.

Muscle cells

A primary cell type responsible for mechanical movement.

Neurons

A primary cell type responsible for electrical communication.

Connective cells

A primary cell type responsible for providing support.

Tissue

A group of cells of the same primary type.

Organ

A combination of different primary tissue types.

Functional unit

The smallest part of an organ that can still perform that organ's specific function.

Redundancy

The structural feature of having multiple functional units so that overall organ function continues if one unit fails.

Expansion

The ability to add additional working functional units without stopping overall organ function.

Extracellular matrix (ECM)

A structural material outside cells, sometimes described as bioglue, that keeps cells together, provides support, and influences survival, growth, and differentiation.

Fibroblasts

Cells associated with constructing the fibrous components of the extracellular matrix.

Collagen

A strong fibrous protein in the ECM that acts like ropes to provide strength and structural support.

Elastin

A flexible fibrous protein in the ECM that acts like rubber bands, allowing structures to stretch and rebound.

Fibronectin

A connector component in the ECM that helps connect collagen and elastin to cells.

Intracellular fluid (ICF)

Fluid located inside cells (cytosol), accounting for approximately $67\%$ of total body water or approximately $28\,\text{L}$ in an adult.

Interstitial fluid (IF)

Extracellular fluid located in the spaces between cells, accounting for approximately $26\%$ of total body water or approximately $11\,\text{L}$.

Plasma

The water portion of blood, accounting for approximately $7\%$ of body water or approximately $3\,\text{L}$.

Polar compound

A compound with an unequal distribution of charge and partial charge separation.

Nonpolar compound

A compound with relatively equal electron sharing and no significant partial-charge separation.

Amphipathic

Describing a molecule that contains both polar and nonpolar regions.

Free radical

A molecule or atom with a single electron in its outer orbit that can remove an electron from another molecule.

Oxidation

The process of removing an electron from a molecule.

Fluid Mosaic Model

A structural model describing the plasma membrane as an organized unit whose diverse components are constantly moving.

Phospholipids

The main structural building blocks of the plasma membrane, composed of a polar head facing outward and two nonpolar tails facing inward.

Cholesterol

A molecule sitting in gaps between phospholipids in an approximate $1:1$ ratio that increases membrane stiffness and heightens the barrier to small polar molecules.