Parts of the Cell & Cell Membranes unit 4

A set of vocabulary flashcards focusing on key concepts related to cellular structure and function as covered in the lecture notes.

Prokaryotic Cells

Cells that lack a nucleus and organelles; genetic material is loose within a nucleoid.

Eukaryotic Cells

Cells with a defined nucleus; genetic material (DNA) enclosed in a phospholipid membrane.

Cytosol

The 'soup' of water and salts that makes up the fluid component of the cytoplasm.

Organelle

Small structures in a cell that perform specific functions, akin to organs in the body.

Gram Stain

A method of staining bacteria to classify them as Gram positive (thick peptidoglycan layer) or Gram negative (thin peptidoglycan layer with lipopolysaccharides).

Gram positive

thick peptidoglycan layer. Stains purple.

Gram negative

thin peptidoglycan layer with lipopolysaccharides. Stains pink.

Plasma Membrane

A phospholipid bilayer that surrounds the cell, controlling what enters and exits.

Phospholipid Bilayer

A double layer of phospholipids that makes up the plasma membrane, with hydrophilic heads and hydrophobic tails.

Ion Channels

Transmembrane proteins that allow specific ions to pass through the cell membrane.

Facilitated Diffusion

The process of transporting molecules across the membrane with the help of carrier proteins.

Endocytosis

The process by which cells take in materials by enveloping them in a membrane to form vesicles.

Exocytosis

The method by which cells expel materials from vesicles that fuse with the plasma membrane.

Osmosis

The movement of water from an area of high concentration to an area of low concentration through a semi-permeable membrane.

Tonicity

The relative concentration of solutes in two solutions separated by a semipermeable membrane, affecting cell volume.

Active Transport

The movement of molecules against their concentration gradient, requiring energy (ATP).

Sodium-Potassium Pump

A primary active transport mechanism that moves sodium out of and potassium into the cell against their concentration gradients.

Phagocytosis

A type of endocytosis where large particles are engulfed by the cell.

Pinocytosis

A form of endocytosis where small amounts of extracellular fluid are taken in by the cell.

Receptor-Mediated Endocytosis

Endocytosis initiated by the binding of ligands to receptors on the cell surface.

Aquaporin

Protein channels that facilitate the transport of water across the cell membrane.

Glycoproteins

Molecules that consist of sugars attached to proteins, playing roles in cell recognition.

Glycolipids

Lipids with carbohydrate chains that contribute to membrane stability and cell recognition.

Cell Identity Markers

Molecules, such as glycoproteins and glycolipids, that are unique to each individual and can trigger immune responses.