OCR A-level Biology- Module 2: Well Defined
Terms with Certified Solutions 2023-2024
Light microscope
An instrument that uses visible light and glass lenses to enable the user to objects
magnified many times
Compound light microscope
A light microscope which uses two lenses to magnify an object; the objective lens,
which is placed near to the specimen and an eyepiece lens, through which the
specimen is viewed
Differential staining
Using specific stains to distinguish different types of cell
Counterstain
Application of second stain with a contrasting colour to sample for microscopy
Electron microscopy
Microscopy using a microscope that employs a beam of electrons to illuminate the
specimen. As electrons have a much smaller wavelength than light they produce
images with higher resolutions than light microscopes
Ultrastructure
The ultrastructure of a cell is those features which can be seen by using an electron
microscope
Artefacts
Objects or structures seen through a microscope that have been created during the
processing of the specimen
, OCR A-level Biology- Module 2: Well Defined
Terms with Certified Solutions 2023-2024
Transmission electron microscope
An electron microscope in which a beam of electrons is transmitted through a specimen
and focused to produce an image
Scanning electron microscope
An electron microscope in which a beam of electrons is sent across the surface of a
specimen and the reflected electrons are focused to produce a three-dimensional image
of the specimen surface
Laser scanning confocal microscope
A microscope that employs a beam of fluorescence and a pin-hole aperture to produce
an image with a very high resolution
Prokaryotic cell
Cells with no membrane-bound nucleus or organelles
Eukaryotic cell
Cells with a nucleus and other membrane-bound organelles
Magnification
How many times larger the image is than the actual size of the object being viewed
Resolution
The ability to see individual objects as separate entities
Cytoplasm
Internal fluid of cells, composed of cytosol (water, salts, organic molecules) , organelles
and cytoskeleton
Terms with Certified Solutions 2023-2024
Light microscope
An instrument that uses visible light and glass lenses to enable the user to objects
magnified many times
Compound light microscope
A light microscope which uses two lenses to magnify an object; the objective lens,
which is placed near to the specimen and an eyepiece lens, through which the
specimen is viewed
Differential staining
Using specific stains to distinguish different types of cell
Counterstain
Application of second stain with a contrasting colour to sample for microscopy
Electron microscopy
Microscopy using a microscope that employs a beam of electrons to illuminate the
specimen. As electrons have a much smaller wavelength than light they produce
images with higher resolutions than light microscopes
Ultrastructure
The ultrastructure of a cell is those features which can be seen by using an electron
microscope
Artefacts
Objects or structures seen through a microscope that have been created during the
processing of the specimen
, OCR A-level Biology- Module 2: Well Defined
Terms with Certified Solutions 2023-2024
Transmission electron microscope
An electron microscope in which a beam of electrons is transmitted through a specimen
and focused to produce an image
Scanning electron microscope
An electron microscope in which a beam of electrons is sent across the surface of a
specimen and the reflected electrons are focused to produce a three-dimensional image
of the specimen surface
Laser scanning confocal microscope
A microscope that employs a beam of fluorescence and a pin-hole aperture to produce
an image with a very high resolution
Prokaryotic cell
Cells with no membrane-bound nucleus or organelles
Eukaryotic cell
Cells with a nucleus and other membrane-bound organelles
Magnification
How many times larger the image is than the actual size of the object being viewed
Resolution
The ability to see individual objects as separate entities
Cytoplasm
Internal fluid of cells, composed of cytosol (water, salts, organic molecules) , organelles
and cytoskeleton
