Unit 1 - Module 1 Glossary Flashcards
Staining
In microscopy it refers to any process that helps to reveal or distinguish different features. In light microscopy, stains may be colours or fluorescent dye. In electron microscopy, they are metal particles or metal salts.
Nanometre
It is equal to one thousandth of a micrometre, therefore is one thousand millionth if a metre. Useful for measuring the sizes of organelles within cells and for measuring the size of large molecules.
Cytoskeleton
This refers to the network of protein fibres found within cells that gives structure and shape to the cell, and also moves organelles around inside cells.
Organelle
A particular structure of a cell that has a specialised function. Some organelles are membrane-bound, others are not. All perform a particular role in the life processes of the cell
Phospholipid belayer
The basic structural component of plasma membranes. It consists of two layers of phospholipid molecules. Proteins are embedded in this layer.
Fluid mosaic
The model of cell membrane structure. The lipid molecules give fluidity and proteins in the membrane give it a mosaic appearance. The molecules can move about.
Cell signalling
Cells communicate with one another by signals. Many molecules act as signals - some signal during processes taking place inside cells; others signal from one cell to others.
Diffusion
The movement of molecules from a region of high concentration of that molecule to a region of lower concentration of that molecule down a concentration gradient.
Active transport
The movement if molecules it ions across membranes, which uses ATP to drive protein ‘pumps’ within membrane.
Osmosis
The movement of water molecules from an area of higher water potential to an area of lower water potential across a partially permeable membrane.
Solute
Solid that dissolves in a liquid.
Solvent
Liquid that dissolves solids.
Solution
Liquid containing dissolved solids.
Cell cycle
The events that take place as one parent cell divides to produce two new daughter cells which then each grow to full size.
Mitosis
The process of nuclear division where two genetically identical nuclei are formed from one parent cell nucleus.
