Cells key words Flashcards
The number of times bigger the image/drawing is compared to the object/real size
Magnification
The minimum distance needed to differentiate between 2 adjacent objects
Resolution
Micrometer
1x10^-6m
Nanometer
1x10^-9m
A type of microscope which has a condenser, objective lens and eyepiece lens and light is passed through the thin specimen and up through the objective and eyepiece lenses to the eye
Light microscope
Beams of electrons are used to visualize structures in a vacuum. Electrons have a smaller wavelength than light so electron microscopes have a higher resolution than light microscopes
Electron microscope
A type of electron microscope which bounces beams of electrons off the surface of an object to develop a 3D image of the specimen (no need therefore for thin sections)
Scanning electron microscope (SEM)
A type of electron microscope which asses a beam of electrons through a very thin section of specimen (which often has been stained with heavy metals to show up the fine internal structures)
Transmission electron microscope (TEM)
The process where cells are broken up and the different organelles they contain are separated out
Cell fractionation
The first stage of cell fractionation when cells are broken up by a homogeniser (blender) and organelles are released from the cell
Homogenation
The second stage of cell fractionation when the fragments in filtered homogenate are separated in a machine called a centrifuge
Ultracentrifugation
A series of lines on a microscope which can be used to calculate the size of objects
Graticule
A cell that has a membrane-bound nucleus and chromosomes. The cell also possesses a variety of other membrane-bound organelles, such as mitochondria and edoplasmic reticulum
Eukaryote
A part of a cell
Organelle
Organelle which contains the hereditary material (DNA) which codes for the synthesis of proteins in cytoplasm
Nucleus
Organelle where energy is released in aerobic respiration
Mitochondria
Organelle that is the site of photosynthesis
Chloroplast
Organelle which provides a large surface area for the synthesis of proteins and glycoproteins and where proteins are transported that are synthesised on ribosomes
Rough endoplasmic reticulum (RER)
Organelle where lipids and carbohydrates are synthesized, stored and transported
Smooth endoplasmic reticulum (SER)
Organelle that contains a stack of membranes that make up flattened sacs (cisternae) where glycoproteins are synthesized, lipids are transported, modified and stores, proteins are packaged and lysosomes are formed
Golgi
Organelle formed when the vesicles produced by the Golgi apparatus contain enzymes. They are where unwanted materials & worn-out organelles are digested
Lysosome
Organelle made of rRNA and protein where protein synthesis occurs
Ribosome
Organelle which provides mechanical strength to prevent the cell bursting under the pressure created by the osmotic entry of water, to give mechanical strength. Made of cellulose in plants and chitin in fungi
Cell wall
Organelle which contains a solution of mineral salts, sugars, amino acids, wastes and sometimes pigments such as anthocyanins. They support herbaceous plants by making cells turgid, may provide a temporary food store and if they contain pigments they may colour petals to attract pollinating insects
Vacuole
A collection of similar cells that perform a specific function
Tissue
A combination of different tissues that are coordinated to perform a variety of functions
Organ
Many organs work together in an organ system to perform a particular function
Organ system
A cell of an organism belonging to the kingdom Prokaryote that is characterized by lacking a nucleus and membrane-bound organelles, e.g. bacteria
Prokaryote
A prokaryote
Bacteria
Small circular loops of DNA which contain genes that bacteria can have
Plasmid
Part of a bacterial cell which helps the bacteria to move
Flagellum
Acellular, non-living particles that are smaller than bacteria. They contain DNA or RNA but can only multiply inside living host cells
Virus
A protein coat which encloses the nucleic acid in a virus
Capsid
The capsid can have these which are essential to allow the virus to identify and attach to a host cell
Attachment protein
