Glossary

• Buffer = solution which resists change in pH when acid or alkali is added to it
• Cell fractionation = technique of separating cellular components while keeping their distinct functions
• Cisternae = flattened, membrane-bound sacs found in the endoplasmic reticulum
• Electrons = subatomic particle with a negative charge
• Eyepiece graticule = pattern of lines or markings built into the eyepiece of an optical device
• Genes = unit of heredity transferred from a parent to offspring holding a particular characteristic
• Homogenation = preparation of a suspension of cell constituents from tissue by physical treatment in a liquid
• Microvilli = microscopic cellular membrane protrusions that increase surface area for diffusion
• Middle lamella = pectin layer which functions to cement two adjoining cells together
• Phagocytic = type of cell within the body capable of engulfing and absorbing bacteria
• Photomicrograph = photograph of a microscopic object, taken with the aid of a microscope
• Resolution = ability of a microscope to distinguish two separate points
• Sediment/pellet = collection of the heaviest organelles during ultracentrifugation
• Stage micrometer = calibration tool used in microscopy to measure the size of the objects being observed under a microscope
• Supernatant = recovered organelle factions of the cell produced after centrifugation
• Ultracentrifugation = technique used to separate particles of different densities in a liquid medium by spinning them at very high speeds
• Villi = fingerlike projections from the surface of certain membranous structures
• Attachment proteins = class of proteins that are present on the surface of viruses and are responsible for binding to specific receptors on the host cell surface
• Capsule of mucilaginous slime = protective layer that surrounds some bacteria
• Plasmids = genetic structure in a cell that can replicate independently of the chromosomes, typically a small circular DNA strand
• Binary fission = type of asexual reproduction where a single living cell or an organelle grows twice its size and splits into two identical daughter cells
• Cancer = a group of diseases caused by uncontrolled cell growth and division
• Chromatin = material of which the chromosomes of organisms other than bacteria are composed of
• Chromosomes = thread-like structures made of DNA that carry genetic information that determines an individual's traits
• Cytokinesis = physical process of cell division which divides the cytoplasm of a parental cell into two daughter cells
• Diploid = containing two sets of chromosomes - one from each parent
• Haploid = having a single set of unpaired chromosomes
• Interphase = the cell is growing and preparing for mitosis
• Mutation = alteration in the DNA sequence of a gene, which can lead to a change in the amino acid sequence of a protein
• Spindle apparatus = segregates chromosomes during cell division to the daughter cells
• Spindle fibres = microscopic protein structures that help divide genetic material during cell division