Vocabulary

Key science words used in this resource, each explained in British Sign Language with a written English description.

Lysis Buffer Lysis Buffer is made up of salt and detergent and it is used to pop open (or lyse) cells. Cell Lysis This is when a cell falls apart because its cell membranes have broken down. Because membranes are mostly lipid… Protease In this experiment we want to protect the DNA from being degraded (broken down into small pieces). Therefore we want to… Alcohol 95-100% Alcohol is used to help us precipitate the DNA. Precipitation DNA is soluble in water however it comes out of solution (or precipitates) when it comes into contact with alcohol. This… DNA Extraction This is the process whereby DNA is extracted from the cell nucleus and precipitated. Enzyme An enzyme is a protein which acts as a biological catalyst. It can speed up a biochemical reaction without being used up… DNA digestion The breaking down of long strands of DNA into smaller fragments. This can be facilitated by enzymes called restriction… DNA fragment A section of DNA which can be of varying length. DNA Fingerprinting A technique which enables the identification of an individual based on similarities or differences in their DNA. Once… Gel Electrophoresis The separation of different sized DNA fragments using electricity and a porous gel (such as an agarose gel). Bacteria A group of single celled micro-organisms. Antibiotic resistance If a bacteria is antibiotic resistant then the antibiotic can no longer kill that bacteria. Genetic Modification The manipulation of the genetic code of an organism Genetic engineering The manipulation of DNA molecules to generate new combinations of genes or sequences. For example, the pGLO plasmid was… Genetically modified organism Any organism, plant, animal or microbe, which has had its genetic code altered artificially. Plasmid A circular piece of DNA found in e.g. bacterial cells. Plasmids are separate from chromosomal DNA and can replicate… Heat shock A technique used to induce bacteria to take up plasmids. Operon A group of genes which are subject to co-ordinated regulation. Transformation The process in which new genetic material is taken up by a cell. For example the bacteria are transformed when they take… Cell Cells are the functional and structural units of all living organisms. Humans are made of many different kinds of cells… Nucleus The nucleus is a membrane-bound organelle (tiny organ) contained within a cell. The chromosomes are found within the… Chromosome In humans chromosomes are found in the nucleus of the cell. Each cell in a human has 23 chromosomes. Each chromosome is… DNA DNA (Deoxyribonucleic acid) is a structure made up of units called deoxyribonucleotides. Each of these nucleotides… Double Helix Under normal conditions, the DNA molecule has the structure of a double helix. mRNA RNA (Ribonucleic acid) is made up of ribonucleotides with the bases adenine, guanine, cytosine or uracil (A,G, C and U).… Protein Most genes code for proteins. Proteins are the functional and structural units in cells. Proteins are made up of amino… Transcription Transcription is the process where an RNA copy of a DNA template (or gene) is produced. It occurs in the nucleus. Translation Following transcription, the messenger RNA is translated into a protein. The mRNA provides a template which structures… Gene A gene is a sequence of nucleotides (contained in a chromosome or a plasmid) which codes for a functional protein (or… Gene Expression When a gene is transcribed into mRNA and translated into a protein it is said to have been expressed. The terms… Genetic code The information for the production of proteins is contained in the nucleotide sequence of a DNA molecule. This sequence…