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29 Cards in this Set
- Front
- Back
- 3rd side (hint)
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What is magnification? |
The number of times larger an imagine appears, compared with the size of the object |
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What is an organelle? |
Small structures within cells, each of which has a specific function |
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What is resolution? |
The clarity of an image, the higher the resolution, the clear the image |
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What is a eukaryotic cell? |
Cells with a nucleus |
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What is a prokaryotic cell? |
Cells without a nucleus |
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What is a optical microscope? |
Uses light focussed through a series of lenses to magnify objects up to several 100 times |
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How do you work out magnification in microscopes? |
Objective lens power X eyepiece power |
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What is an electron microscope? |
Use short wavelengths of electrons to produce high resolution images of extremely small objects |
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What is a transmission electron microscope TEM |
Electrons pass through the specimens and are scattered. Some electrons pass through the specimens and Magnetic lenses focus the image onto a floured vent screen or photographic plate. |
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What is a scanning electron microscope SEM |
Scans a sample with a beam of primary electrons, which knocks electrons from the samples surface. Electrons are picked up by a collector, amplified and transmitted onto a viewing screen or photographic plate producing a 3D image |
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What is the resolution of an optical microscope? |
250 NM |
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What is the resolution of an electron microscope? |
0.1 NM |
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What is a eyepiece graticule? |
A measuring device. Placed in the eyepiece of a microscope and acts as a ruler when you view an object under the microscope |
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What is an stage graticule? |
A precise measuring device. A small scale that is placed on a microscope stage and used to calibrate the value of eyepiece divisions at different magnifications |
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What is the function of mitochondria? |
They are the cell's energy transformers converting chemical energy into ATP Both plant and animal cells |
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What is the function of chloroplasts |
Contain dense stacks of membranes with colourless fluid. They are the sites of photosynthesis and occur mainly in leaves |
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What is the function of a cell wall? |
Composed mainly of cellulose and supports the cell and limits its volume- controls what goes in and out |
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What is the function of plasma membrane? |
Located inside the cell wall in plants. Provides support
In animals it provides support and controls what goes in and out |
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What is the function of Endoplasmic reticulum? |
Compromises a network of tubes and flattened sacs. It may be smooth and have ribosomes attached in plants
In animals RER is a site of protein synthesis it also synthesises new membranes growing in place by adding proteins and phosphoilpids
SER is a site of lipid and carbohydrate metabolism and hormone synthesis |
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What is the function of ribosomes? |
Manufacturing proteins, in plants and Animals they may be free in the cytoplasm or on ER |
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What is the function of cytoplasm? |
A watery solution containing dissolved substances, enzymes and the cells organelles and structures. The site of translation |
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What is the function of nucleolus? |
Involved in ribosome synthesis and contains protein and nucleic acid |
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What is the function of Golgi apparatus? |
To store modifiy and package proteins. It tags proteins so they go to their correct destination |
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What is the function of centrioles? |
Associated with nuclear division. Composed of microtubles |
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What is the function of nuclear pore |
A whole in the nuclear membrane allowing the nucleus roc communicate with the rest of the cell |
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What is the function of lysosomes |
They pinch off from the Golgi and contain and transport enzymes that break down food. |
Non membrane bound |
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What is the function of cytoskeleton |
To keep the cells shape stable "internal scaffold"
Long chains within a cell made up of proteins
actin filaments which are lengths of proteins responsible for the movement of white blood cells.
Microtubules tublues of proteins- made from tubulin and can: move micro organisms through a liquid Can move liquid over a cell Can move chromosomes They can also move vesicles from the ER to the Golgi |
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What do eukaryotic cells have that prokaryotes dont |
Nucleus ER Golgi apparatus Mitochondria Chloroplasts Vacuole |
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What do prokaryotes have that eukaryotes dont |
Mesosomes Capsules Pilus |
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