Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MOL. BIO LAB > PRELIM LAB 2: INSTRUMENTATION > Flashcards

PRELIM LAB 2: INSTRUMENTATION Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

A process by which it MEASURE THE AMOUNT OF LIGHT THAT CAN PASS THROUGH A SOLUTION to determine the concentration of the light-absorbing substance in the solution

A

SPECTROPHOTOMETRY

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

“Absorbance is DIRECTLY PROPORTIONAL to the concentration of the solution”

__________ LAW

A

BEER - LAMBERT LAW

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

amount of light absorbed as incident light passes through a sample

A

ABSORBANCE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

proportionality constant/a compound that is the measure of the absorption of radiant energy

A

MOLAR REABSORPTIVITY

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

SPECTROPHOTOMETRY COMPONENTS:
Emits a broad spectrum of light

A

LIGHT SOURCE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

MOST COMMON LIGHT SOURCE

A

INCANDESCENT TUNGSTEN/ TUNGSTEN - IODINE LAMP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

visible & UV, do not heat up the instrument, reduce warm up time

A

XENON FLASH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

SPECTROPHOTOMETRY COMPONENTS:
Isolation of individual wavelengths of light

A

MONOCHROMATOR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

SPECTROPHOTOMETRY COMPONENTS:
Causes different wavelength of light to be dispersed in different angles

A

DISPERSION DEVICE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

DISPERSION DEVICE TYPES:
- (glass = visible range,3x dispersion than quartz, quartz = visible light & UV)
- Transparent optical elements with flat/curved surfaces that can refract light
- As light passes through it, it is REFRACTED based on the varying refractive indices of different wavelength

A

PRISM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

DISPERSION DEVICE TYPES:
- Absorbs/reflects certain wavelengths & transmitting other wavelengths

A

FILTER

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

ABSORB short wavelengths, transmit long wavelengths

A

ABSORPTION FILTERS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

SELECTIVELY TRANSMIT/reflect a certain range of wavelengths; with dielectric films

A

INTERFERENCE FILTERS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

DISPERSION DEVICE TYPES:
(most commonly used)
- Optical components with closely parallel lines/grooves/ruling on its surface (15,000 or 30,000 per inch)
- When the light strikes the gratings, it undergoes DIFFRACTION
- Wavelengths bend as they pass a sharp corner

A

DIFFRACTION GRATINGS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

SPECTROPHOTOMETRY COMPONENTS:
- Small, transparent vessel used to hold a liquid sample to be analyzed
- Scratches may scatter light
- Material:
Glass
Quartz
Plastic
- Shapes:
Rectangular
Cylindrical

A

SAMPLE CELL (CUVETTE)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

SPECTROPHOTOMETRY COMPONENTS:
- Convert the transmitted radiant energy into an equivalent amount of electrical energy, which can be measured & analyzed
- Types:
Barrier layer/photocell
Phototube
Photomultiplier tube (PMT)

A

PHOTODETECTORS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

SPECTROPHOTOMETRY CLASSES:
- Only 1 light path that passes through both the reference and sample cells
- Alternates between measuring the reference (blank) & the sample

A

SINGLE BEAM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

SPECTROPHOTOMETRY CLASSES:
- 2 separate light paths (for sample & reference)
- Measure blank & the sample simultaneously

A

DOUBLE BEAM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

1 photodetector, with chopper/splitter

A

DOUBLE BEAM IN TIME

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

2 photodetectors (for sample & reference

A

DOUBLE BEAM IN SPACE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q
  • Determines the concentration via EXCITATION of the substance via electromagnetic radiation

PRINCIPLE:
- A substance absorbs light energy at a certain wavelength (excitation) and then re-emits light at a longer wavelength (emission)

A

FLUORESCENCE

22
Q

FLUORESCENCE COMPONENTS:
- Provides excitation light that is used to illuminate the sample
- Gas discharge lamps (xenon & mercury arc)

A

LIGHT SOURCE

23
Q

FLUORESCENCE INTENSITY of fluorophore is reduced (factors: pH, temperature, contamination, UV light changes)

A

QUENCHING

24
Q

FLUORESCENCE COMPONENTS:
- CONTROL THE INTENSITY OF EXCITATION LIGHT and optimize the measurement conditions

A

ATTENUATOR

25
Q

FLUORESCENCE COMPONENTS:
USED TO SELECT SPECIFIC EXCITATION WAVELENGTH, ensuring that only light of desired wavelength reaches the sample.

A

PRIMARY FILTER (EXCITATION MONOCHROMATIC/FILTER)

26
Q

FLUORESCENCE COMPONENTS:
Holds the sample being analyzed (cuvette)

A

SAMPLE HOLDER

27
Q

FLUORESCENCE COMPONENTS:
Used to select a specific wavelength

A

SECONDARY FILTER (EMISSION MONOCHROMATIC/FILTER)

28
Q

FLUORESCENCE COMPONENTS:
- Capture and measures the intensity of the emitted fluorescence

A

DETECTOR

29
Q
  • Excitation of the substance in the sample is caused by a CHEMICAL, BIOCHEMICAL or , ELECTROCHEMICAL reaction
  • Emission is measured by LUMINOMETERS
    -No monochromator or light source
A

LUMINESCENCE

30
Q

Emission of light resulting from chemical reaction wherein chemical energy is directly converted into light energy

A

CHEMILUMINESCENCE

31
Q

Chemiluminescence found in biological (organ) systems (certain fungi, bacteria, jellyfish, fireflies)

A

BIOLUMINESCENCE

32
Q

Luminescence resulting from electrochemical reaction

A

ELECTROCHEMILUMINESCENCE

33
Q

Most commonly used electrochemiluminescence label

A

Ruthenium (Ru2+) & tris (bipyridyl) chelate:

34
Q

are ULTRASENSITIVE with WIDE DYNAMICS RANGES, & is utilized in molecular biology laboratory

A

CHEMILUMINESCENCE ASSAYS

35
Q

DEPENDS ON WAVELENGTH & particle size & measurements have been applied to immunoassays of specific proteins & haptens

A

LIGHT SCATTERING DEVICES

36
Q
  • Determines the AMOUNT OF LIGHT BLOCKED (light reduction) by a particulate matter in a turbid solution
  • When particles are present in the sample, they scatter & absorb light, reducing the amount of light that reaches the detector
  • Applications: protein measurements (CSF & urine); bacterial growth detection in broths, AST (antimicrobial susceptibility) in broths, detection of clots
A

TURBIDIMETRY

37
Q

Determines the AMOUNT OF SCATTERED LIGHT (at an angle 90 degrees from the indecent light) by a particular matter suspend in a turbid solution
Physical phenomenon that results from light particle interactions in a solution
Application: antigen-antibody complexes (proteins)

A

NEPHELOMETRY

38
Q

detector is positioned IN LINE with the incident light beam

A

Turbidimetry

39
Q

detector is placed PERPENDICULAR to the incident light beam

A

Nephelometry

40
Q
  • Used to identify presence of relatively small number of metal ions in a compound
  • Heat of the flame converts the metal ions into atoms which become excited and emit visible light
A

FLAME TESTS

41
Q
  • Measures the light emitted by a single atom burned in a flame
  • Principle: excitation of electrons from lower to higher energy state
  • Cuvette & light source: flame
    For the determination of sodium, potassium, lithium, & other metal/ions
A

FLAME EMISSION PHOTOMETERS

42
Q

SODIUM

A

589 nm, yellow

43
Q

potassium

A

66nm, violet

44
Q

lithium

A

670 nm , red

45
Q
  • Based on INTERACTION OF RADIANT ENERGY with suitably excited atoms/molecules
  • For determination of structure, ID of samples, quantification, diagnosis
  • Employed in hematology as flow cytometers for the differential analysis of WBCs
    Side scatter: complexity/granularity of cell
    Forward scatter: size of cell
A

LASER SPECTROPHOTOMETRY

46
Q
  • Measures the light absorbed by atoms dissociated by heat
    Principle: an element is not excited by merely dissociated from its chemical bond & placed in unionized, unexcited ground state
    Light source: hollow - cathode lamp
    Cuvette: flame
    Very precise & for detection of metals and heavy metals
A

ATOMIC ABSORPTION SPECTROPHOTOMETRY

47
Q

ELECTROCHEMICAL DEVICES:
- Measures the CONCENTRATION OF SPECIFIC IONS in a solution by responding to that particular ion

A

ION SELECTIVE ELECTRODES

48
Q

ELECTROCHEMICAL DEVICES:
- Measures the acidity/alkalinity (pH) of a solution

A

pH ELECTRODES

49
Q

ELECTROCHEMICAL DEVICES:
- Detects the presence and concentration of specific gasses in a given environment

A

GAS SENSING ELECTRODES

50
Q

ELECTROCHEMICAL DEVICES:
- Migration of charged solutes/particles in an electrical field (macromolecules of interest are proteins, nucleic acids)
- Rate of movement is influenced by the size and charge of the particles, leading to their separation based on these characteristics

A

ELECTROPHORESIS

51
Q

ELECTROCHEMICAL DEVICES:
- Measure the concentration of solute particles in a solution (osmotic concentration)

A

OSMOMETRY

MOL. BIO LAB (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions