Microscopy Skills Flashcards
What is the Cell Theory
All living things are made of cells
Cells come from pre-existing cells
Cells are the basic unit of life
Three Magnification Formulas
I = A * M
M = I / A
A = I / M
Difference between Light and Electronic Microscope
Light microscope uses light
Electronic uses electrons
Light microscope can use stains to improve viewing
Electron microscope can’t
Light microscopes are cheap
Electron microscopes are expensive
Light microscopes are easily used
Electron microscopes require training
Light microscope can have specimen dead or alive
Electron microscope needs specimen to be dead
Difference with Magnification and Resolution
Magnification: The size of the image enlarged
Resolution: How clear the image is
Freeze-fracture Electron Microscopy
Used to produce images of surfaces of cells
The sample gets frozen
A steel blade is used to cut the cell’s weak point and some of the ice is removed by vaporization
The sample gets etched with platinum or carbon to form a coating
The replica is removed from the frozen sample and can be examined using an electron microscope
Cryogenic Electron Microscopy
Used for researching the structure of proteins
A thin layer of pure protein solution is applied to a grid
Sample gets rapidly frozen then fractured
This enables an image to be formed from a computer to show the three dimensional framework of proteins
Immunofluorescence
Used to find out if a protein is being produced in a cell
Fluorescent stains bind with specific antibodies
This can help identify the marked antibody and find out about its function
Prokaryote Structures:
Nucleoid Region: Region containing the naked DNA which stores genetic information that controls the cell and initiates binary fission
Cell Wall: Protects the cell from the outside environment, maintains the shape of the cell, and prevents it from bursting
Plasma Membrane: Controls what substances enter and leave the cell
Cytoplasm: The site of all chemical reactions
Pili: Help bacteria attach to each other to exchange genetic information
Flagella: Locomotion
Ribosomes: Protein Synthesis
Plasmid: Helps the bacteria adapt to unusual situations
Ribosome
Small spherical structure that can either be attached to the RER or free in the cytoplasm
When free in the cytoplasm, they make proteins for the cell
When attached to the RER, they make proteins to export from the cell
Endoplasmic Reticulum
RER: A network of membranes that have ribosomes attached to its surface
SER: A network of smaller membranes with no ribosomes
RER synthesizes proteins and transports them
SER produces lipids such as membrane phospholipids and sex cells
Lysosome
Arise from the Golgi Apparatus, and contain many digestive enzymes that digest structures that are not needed in the cell
Golgi Apparatus
Consists of flattened sacs called cisternae. Has a cis side which receives products and a trans side which is where vesicles are discharged
They receive proteins and modify them and packages the proteins into vesicles to be sent to the plasma membrane
Mitochondria
Produces ATP
Nucleus
The region that contains chromosomes which is responsible for controlling the cell
Nucleolus
Synthesizes Ribosomes
Centrosomes
Cell movement and Cell division
Chloroplast
Photosynthesis
Vacuoles
Are a large sac that store food, water, and toxins and allows an uptake of water to provide turgidity of the cell
Advantages of Compartmentalization
Efficiency of metabolism
Localized conditions
Toxic or damaging substances can be isolated
Number and location of organelles can be changed depending on cell’s requirements
