Membranes and Transport; Cell Structure and Function

A set of flashcards summarizing key vocabulary and concepts related to membranes, transport mechanisms, and cell structure and function.

Fluid mosaic model

The model describing the structure of cell membranes as a mosaic of various components, including phospholipids and proteins.

Phospholipid bilayer

A double layer of phospholipids that makes up the cell membrane.

Integral membrane protein

Proteins that are embedded within the lipid bilayer of a membrane.

Peripheral membrane protein

Proteins associated with but not embedded within the lipid bilayer.

Cholesterol

A lipid that is found within the phospholipid bilayer, impacting fluidity.

Glycoprotein

A protein that has carbohydrate chains attached, playing key roles in cell recognition.

Permeability

The ability of a membrane to allow substances to pass through.

Amphipathic

Molecules that have both hydrophilic and hydrophobic parts.

Diffusion

The passive movement of molecules from an area of higher concentration to an area of lower concentration.

Osmosis

The passive movement of water across a selectively permeable membrane.

Isotonic

A solution with the same solute concentration as another solution.

Hypertonic

A solution with a higher solute concentration compared to another solution.

Hypotonic

A solution with a lower solute concentration compared to another solution.

Selectively permeable membrane

A membrane that allows certain molecules to pass through while blocking others.

Passive transport

The movement of molecules across a cell membrane without the use of energy.

Active transport

The movement of molecules across a cell membrane using energy, typically against their concentration gradient.

Facilitated diffusion

The process of transporting materials through a cell membrane using proteins, without energy.

Carriers

Proteins that bind to molecules and change shape to shuttle them across the membrane.

Channels

Protein structures that allow specific molecules to pass through a membrane.

Na+/K+ pump

An active transport mechanism that pumps sodium out of and potassium into the cell.

ATP

Adenosine triphosphate; the energy currency of the cell.

Prokaryote

A unicellular organism lacking a nucleus and membrane-bound organelles.

Eukaryote

An organism made up of cells that have a nucleus and membrane-bound organelles.

Archaea

One of the three domains of life, consisting of prokaryotic organisms that often thrive in extreme conditions.

Bacteria

Single-celled prokaryotic organisms, classified under the domain Bacteria.

3 domains of life

The three major categories of life: Bacteria, Archaea, and Eukarya.

Cell membrane (plasma membrane)

The biological membrane that separates and protects the contents of a cell.

Cytoplasm

The jelly-like substance within a cell that contains organelles and cytoskeleton.

Ribosomes

Molecular machines that synthesize proteins by translating messenger RNA.

Genetic material (DNA)

The hereditary material in organisms that carries the genetic instructions.

Cytoskeleton

A network of fibers that provides structural support for the cell.

Nucleoid region

The area in prokaryotic cells where the DNA is located.

Cell wall

A rigid layer that gives structure and protection to some cells.

Capsule

A protective layer that surrounds some prokaryotic cells, aiding in their survival.

Pili

Hair-like structures on the surface of some prokaryotic cells that aid in attachment.

Flagellum

A long, whip-like structure that aids in cell motility.

Mitochondria

Organelles known as the powerhouse of the cell, where ATP is produced.

Nucleus

The membrane-bound organelle that contains the cell's genetic material.

Nuclear envelope

The double membrane that encloses the nucleus.

Nuclear pore

Large protein complexes that allow molecules to move in and out of the nucleus.

Nucleolus

A structure within the nucleus where ribosomal RNA is produced.

Chromatin/chromosomes

The form of genetic material in the nucleus; chromatin is the relaxed form, while chromosomes are the coiled form during cell division.

Rough endoplasmic reticulum

The portion of the endoplasmic reticulum that has ribosomes attached, involved in protein synthesis.

Smooth endoplasmic reticulum

The portion of the endoplasmic reticulum without ribosomes, involved in lipid synthesis.