Flashcards
OCR- AS Biology- Unit 1, Module 1- Cells Questions
Flashcards do conjunto (10)
- 1What three things did Schwann and Schleiden say about cells?-All living things consist of cells
-New cells are formed from the division of old cells
-Instructions for growth are passed on to new cells - 2What is the magnification and resolution of a light microscope?x1500 magnification
200nm resolution - 3Which of TEM and SEM has a greater magnification?TEM
- 4What is the resolution of both TEM and SEM?0.2nm
- 5What is the definition of magnification?Th number of times greater an image is than the object
- 6What is the definition of resolution?The ability to distinguish two separate points that are distinct from each other.
- 7Why is a stain required in light microscopy?This allows the different parts of a cell to become distinct from each other and creates definition.
- 8What stain is used in TEM and what will the image look like?Electrons pass through the sample- the more dense the sample, the longer it will take. False colour is applied afterwards to define between the different parts and this produces a 2D image
- 9Why is a gold stain used in a SEM?The gold stain allows the electrons fired at the sample to 'bounce' off, creating a 3D image that shows the contours of the specimen.
- 10What is the equation for magnification?Magnification= Image/ Actual
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- A Levels Biology (AS Biology) FlashCards sobre OCR- AS Biology- Unit 1, Module 1- Cells Questions, criado por Laura Perry em 18-02-2015.
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- Laura Perry
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