M2 C2 Cells Flashcards
define magnification
the number of times greater an image is than the object
define resolution
- the ability to distinguish between 2 points - the clarity of an image
what are the 3 main points of cell theory
- both plant and animal tissue is composed of cells - cells are the basic unit of all life - cells only develop from existing cells
what is a photomicrograph
a photograph taken through a microscope
what energy source do ___ microscopes use
- optical/light
- laser scanning confocal
- Scanning electron microscope
- Transmission electron microscope
- light
- light
- electrons
- electrons
is a vacuum necessary for ___
- optical/light
- laser scanning confocal
- Scanning electron microscope
- Transmission electron microscope
- no
- no
- yes
- yes
what is ___ microscope used to view
- optical/light
- laser scanning confocal
- Scanning electron microscope
- Transmission electron microscope
- 2.
3.
4.
what resolution can be achieved by a ___ microscope
- optical/light
- laser scanning confocal
- Scanning electron microscope
- Transmission electron microscope
- 50-200 nm
- high- varies
- 3-10 nm
- 0.05-1.0 nm
explain the need for staining samples for use in light microscopes
many biological structures are colourless therefor stains are used to increase contrast in a specimen so that the components can become more visible & identified
how do you calculate magnification
magnification= image/actual
what are the advantages of using a ___ microscope
- optical/light
- laser scanning confocal
- Scanning electron microscope
- Transmission electron microscope
- relatively cheap, easy to use (portable). can study living specimens
- can focus on one focal plane at a time w/ a cell thus build up a 3D image
- v high magnification & resolution
- v high magnification & resolution
what are the disadvantages of using a ___ microscope
- optical/light
- laser scanning confocal
- Scanning electron microscope
- Transmission electron microscope
- long wavelength of light gives limited magnification due to low resolution
- lower resolution than EM, only see fluorescent objects which can cause artefacts
- v expensive requires high level of training, NOT able to view living material & artefacts are likely
- v expensive requires high level of training, NOT able to view living material & artefacts are likely
DESCRIBE THE STRUCTURE OF CHLOROPLAST [5]
- A double membrane structure and contain a fluid called stroma
- have an internal network of membranes which form flattened sacs called thylakoids
- Several thylakoids stacked together form a granum which are joined by membranes called lamellae
- The grana contain chlorophyll pigments
- Chloroplasts contain DNA & ribosomes :. Can make proteins
WHAT IS THE FUNCTION OF CHLOROPLAST
To carry out photosynthesis
DESCRIBE THE STRUCTURE OF GOLGI [2]
- Similar in structure to smooth endoplasmic reticulum
- Formed of cisternae, does NOT contain ribosomes