Lab Components Flashcards
Ninhydrin Test
- Tests for presence of amino acids
- Positive test will yield purple
- NEVER BOIL OR HEAT UP
Dische Diphenylamine
Reacts with deoxyribose sugar in DNA and forms a blue complex
Biuret Test
- Reacts specifically with peptide bonds formed between amino acid groups.
- Colour changed from blue to violet in the presence of proteins (long amino acids)
- Colour changes from blue to light purple in the presence of peptides (short chains)
Starch (Iodine) Test
- Tests for the presence of starch (aka Polymer Amylose)
- Positive test for starch will yield blue/black
- Positive test for glycogen will yield reddish brown
Barfoed’s Test
- Tests for the presence of monosaccharides
- Positive test will yield a red precipitate
Benedict’s Test
- Tests for reducing sugars in monosaccharides and many disaccharides
- Positive test will form a precipitate ranging in colour from green to red/brown
Serial Dilution
Dilution that greatly amplifies the dilution factor between each step in the experiment
Miscibility test
Test for lipids
Hydrolysis
Adding water to molecules (H and OH) to break covalent bonds and form a new model
Dehydration synthesis
Removes water (H and OH) ion from molecules to form a new model
Depth of focus
Part that is clear when viewing a slide on a microscope and the rest is blurry
Simple staining
Does not offer any diagnostic information as it simply dyes the specimen for better viewing
Diagnostic staining
Shows membrane bound organelles
Transmission electron microscope
- Specimens are stained with metal to absorb electrons and enhance contrast
- Shows image of internal cellular structure
Scanning electron microscope
- Directs electron beam over pre-coated specimen
- Provides 3D image, chemical composition, electrical properties and structural characteristics
- Only look at dead cells because electrons would destroy a live sample
Concave lens
Imports a real image that is right side up
Convex lens
Imports an virtual inverted upside down image
Dissecting microscope
Contains only a concave lens rendering a real 3D image
Parfocal
When a slide is in focus with lowest power and it should almost be focused with the next highest lens
Peptone
A protein that is formed by partial hydrolysis under acidic conditions
Albumin
A single protein in animal and plant fluids and tissues
Amyloplast
A plastid in plant cells that are double enveloped organelles
Tonoplast
Semi-permeable membrane surrounding a vacuole in plant cells that regulates movement of ions around the cell
Central vacuole
Large vacuole in plants that are filled with fluids and molecules
Betacyanin
Red pigment in beet cells
Centrosome
Cellular structure involved in cell division
Vacuole
Organelle in eukaryotes that sequester waste product in animals and maintains water balance in plants
Passive transport
Type of membrane transport that doesn’t require energy as it goes along concentration gradient and moves molecules from high [ ] to low [ ]
Brownian movement
Random movement of microscopic particles suspended in liquid or gas
Solute
A substance that is dissolved in a solution
Solvent
A substance that is capable of dissolving substances
Agar
A petri dish that contains a growth medium solidifies with agar to culture microorganisms
Osmosis
Movement of water molecules in a solution with high [ ] to an area of low [ ] through a semi-permeable membrane
Osmosis in animal cells
helps with absorbing water from intestines into blodd
Osmosis in plant cells
Responsible for absorption of water from soil and conducting it to the upper parts of a plant
Diffusion
Particles move from an area of high [ ] to an area of low [ ] until equilibrium is reached
Turgidity
When the cells membrane pushes against the cell wall when turgor pressure is high (when turgor pressure is low plant is flaccid)
Flaccid
When turgor pressure is low so plant is floppy, wilted and loose
Tonicity
The ability to make water move in and out of the cell by osmosis (hypertonic, hypotonic and isotonic)
Hypertonic solution
A net movement of water OUT of the cell, causing it to lose volume
(A solution is hypertonic to a cell if the solute [ ] outside cell is higher than inside cell)
Hypotonic solution
A net movement of water INTO the cell, causing it to gain volume
(A solution is hypotonic to a cell if the solute [ ] outside the cell is lower than inside the cell)
Isotonic solution
No net movement of water and the cell stays the same
Turgor pressure
Prevents the cell bursting in plants from hypotonic solution
Plasmolysis
When cells lose water to a hypertonic solution (becomes flaccid)
Deplasmolysis
When a plant cell becomes hypotonic and regains turgor pressure
Crenated cells
When red cells change their shape from being exposed to a hypertonic solution
Hemolysis
Breaking down of red blood cells
Lysis
Break down of a cell from damage to the plasma membrane
