Unlock hundreds more features
Save your Quiz to the Dashboard
View and Export Results
Use AI to Create Quizzes and Analyse Results

OR
Sign inSign in with Facebook
Sign inSign in with Google
Quizzes > Science > Biology

Microbiology Test 3: Chapter 3 Cell Size Quiz

Think you can ace this microbiology chapter 3 quizlet? Dive in!

Difficulty: Moderate
2-5mins
Learning OutcomesCheat Sheet
Paper art bacteria viruses on sky blue background quiz Microbiology Test 3 Chapter cell sizes magnification

Ready to tackle the ultimate microbiology test 3 challenge? Our Microbiology Test 3: Chapter 3 Size Quiz invites you to dive into cell dimensions, compare viruses and bacteria, and master magnification techniques. Perfect for class prep, lab study sessions, or a quick review before exams, whether you've been reviewing with a microbiology chapter 3 quizlet or refining your chapter 3 microbiology questions, this virus bacteria size quiz and cell magnification quiz questions practice will put your knowledge to the test. Access our microbiology exam 3 test and sharpen your skills with a hands-on microbiology practice test. Don't just study - prove your expertise now!

What is the typical diameter of Escherichia coli?
0.2 µm
5 - 10 µm
1 - 2 µm
10 - 20 µm
Escherichia coli cells are rod-shaped bacteria typically measuring about 1 - 2 µm in length and about 0.5 µm in width. This size allows them to be easily observed under a light microscope using oil immersion. Their dimensions are standard in many microbiology textbooks. source
Which unit is most appropriate for measuring viral particles?
Micrometers (µm)
Nanometers (nm)
Millimeters (mm)
Centimeters (cm)
Viruses are extremely small, generally ranging from 20 to 300 nm in diameter, making nanometers the appropriate unit for their measurement. Micrometers are too large and would not provide sufficient precision. This is why electron microscopy, which resolves down to nanometers, is used for viral imaging. source
The typical size range for prokaryotic cells is:
1 - 10 µm
0.1 - 1 µm
100 - 1000 µm
10 - 100 µm
Most prokaryotic cells, including bacteria and archaea, fall within the 1 - 10 µm size range. Cells smaller than 1 µm are rare and typically obligate intracellular organisms. Larger sizes are usually associated with eukaryotic microorganisms. source
A red blood cell is approximately what diameter?
7 µm
20 µm
50 µm
2 µm
Human red blood cells are typically about 6 - 8 µm in diameter, with 7 µm being an average. This size allows them to pass through capillaries and maximize surface area for gas exchange. They are larger than most bacteria but smaller than many eukaryotic cells. source
Which of the following is the smallest?
Virus
Yeast cell
Bacterium
Protozoan
Among these options, viruses are the smallest, typically measuring 20 - 300 nm. Bacteria are larger at around 1 - 2 µm, yeast around 5 - 10 µm, and protozoa often exceed 10 µm. Viruses require electron microscopy for visualization. source
The unit micrometer (µm) is equivalent to:
10?? meters
10?³ meters
10?? meters
10?¹² meters
A micrometer (µm) equals 10?? meters. This unit is commonly used to measure bacteria, eukaryotic cells, and other microscopic organisms. Understanding metric prefixes is essential in microbiology. source
Which microscope type is most frequently used to view bacterial cells in a teaching lab?
Fluorescence microscope
Transmission electron microscope
Scanning electron microscope
Compound light microscope
The compound light microscope is the standard tool in teaching labs for observing stained bacterial cells at magnifications up to 1000×. Electron microscopes provide higher resolution but are expensive and require specialized training. Fluorescence microscopes are used for specific labeling techniques. source
What is the typical magnification of an ocular (eyepiece) lens in a compound microscope?
100×
10×
40×
4×
Ocular lenses in compound microscopes are most often 10×, which combined with objective lenses yields total magnifications of 40× to 1000×. Some microscopes have 15× or 20× eyepieces, but 10× is standard. source
Simple staining with methylene blue primarily reveals what feature of bacterial cells?
Motility
Shape and arrangement
Internal organelles
Cell viability
Simple staining involves applying a single dye, like methylene blue, which binds to negatively charged cell components and reveals cell shape, size, and arrangement under a light microscope. It does not provide information on motility or viability. source
Magnification in microscopy refers to:
The increase in resolution between two points
The numerical aperture of the objective lens
The contrast of the specimen against the background
The apparent enlargement of an image
Magnification is the process of enlarging the appearance of an object via lenses. It does not guarantee better resolution or contrast. Resolution refers to the ability to distinguish two distinct points. source
Resolution in microscopy is defined as:
The intensity of illumination
The contrast between specimen and background
The power to enlarge an image
The minimum distance two points can be distinguished
Resolution, or resolving power, is the ability of a microscope to distinguish two adjacent points as distinct. Higher resolution yields clearer detail. It depends on wavelength of light and numerical aperture. source
Which part of the microscope adjusts the diameter of the light beam reaching the specimen?
Stage
Ocular lens
Condenser
Diaphragm
The diaphragm, often part of the condenser, controls the diameter of the light beam passing through the specimen, influencing contrast and resolution. Opening it more increases light intensity but may reduce contrast. source
The coarse focus knob is used for:
Adjusting illumination intensity
Making large adjustments to focus at low power
Fine adjustments to focus at high power
Changing objective lenses
The coarse focus knob moves the stage or objective rapidly to bring the specimen roughly into focus, typically used with low-power objectives (4× and 10×). Fine focus is used for detailed adjustments at higher magnifications. source
The fine focus knob is primarily used for:
Regulating light source voltage
Switching between objectives
Fine, precise adjustments in focus
Large, rapid changes in focus
The fine focus knob makes small, precise movements to sharpen the image, especially important at high magnifications (40× and 100×). It allows minimal vertical movement of the stage or lens. source
Gram-negative bacteria's peptidoglycan layer is approximately:
10 - 20 nm
2 - 3 nm
200 - 300 nm
50 - 100 nm
Gram-negative bacteria have a thin peptidoglycan layer about 2 - 3 nm thick, sandwiched between the inner cytoplasmic membrane and an outer membrane. This thin layer is why they appear pink in Gram staining. source
The approximate diameter of an influenza virus particle is:
20 nm
100 nm
800 nm
200 nm
Influenza viruses are roughly spherical particles about 80 - 120 nm in diameter, with 100 nm being a convenient average. Their size places them well below the resolution of light microscopes. source
Parvovirus is one of the smallest DNA viruses. What is its approximate diameter?
200 nm
20 nm
0.2 mm
2 µm
Parvoviruses are very small, single-stranded DNA viruses about 18 - 26 nm in diameter. Their small size necessitates electron microscopy for visualization. source
A typical bacteriophage head width is around:
5 nm
50 nm
5 µm
500 nm
Many bacteriophage heads range around 50 - 100 nm in diameter. This size is characteristic of tailed phages like T4. Accurate measurement requires electron microscopy. source
The resolving power of the human eye under ideal conditions is approximately:
1 µm
1 nm
0.1 µm
0.1 mm
The human eye can resolve details down to about 0.1 mm (100 µm) under ideal conditions, which is far larger than microscopic organisms. Microscopes are necessary for smaller structures. source
What is the total magnification when using a 40× objective lens and a 10× eyepiece?
400×
4000×
40×
100×
Total magnification is calculated by multiplying the eyepiece magnification (10×) by the objective magnification (40×), giving 400×. This is commonly used for detailed observations of bacteria. source
If a specimen measuring 2 µm is magnified 1000×, its apparent size would be:
20 mm
2 µm
0.2 mm
2 mm
When magnified 1000×, a 2 µm object appears to be 2 mm in size (2 µm × 1000 = 2000 µm = 2 mm). Understanding this conversion is crucial for interpreting microscopic images. source
Which statement is true regarding microscope working distance?
It depends only on eyepiece design
It decreases as magnification increases
It remains constant regardless of objective
It increases as magnification increases
Working distance, the space between the objective lens and specimen, decreases as objective magnification increases because higher magnification lenses have shorter focal lengths. This can impact sample preparation. source
Which microscopy technique provides the best average resolution of about 200 nm?
Light (optical) microscopy
Transmission electron microscopy
Confocal laser scanning microscopy
Scanning electron microscopy
Conventional light microscopy has a resolution limit of roughly 200 nm due to the wavelength of visible light and numerical aperture constraints. Other techniques like electron microscopy achieve much higher resolution. source
Which microscope uses a beam of electrons transmitted through a thin specimen?
Scanning electron microscope
Phase-contrast microscope
Transmission electron microscope
Dark-field microscope
A transmission electron microscope (TEM) transmits electrons through a thinly sliced specimen to form an image, offering resolutions down to 0.2 nm. SEM, by contrast, scans the surface and provides 3D topographical images. source
Which microscope produces three-dimensional surface images by detecting scattered electrons?
Scanning electron microscope
Phase-contrast microscope
Transmission electron microscope
Dark-field microscope
Scanning electron microscopes (SEMs) detect electrons scattered from a specimen's surface, producing detailed 3D images of topography. They have lower resolution than TEMs but greater depth of field. source
Which objective lens typically requires oil immersion for optimal resolution?
100×
4×
10×
40×
Oil immersion objectives, usually 100×, require immersion oil to match the refractive index between the glass slide and lens, minimizing light refraction and improving resolution. Lower-power lenses do not use oil. source
Confocal laser scanning microscopy is especially useful for:
Routine bright-field imaging
3D reconstruction of fluorescent samples
Surface topology of metals
Live cell ultrastructure imaging
Confocal laser scanning microscopy uses point illumination and a spatial pinhole to eliminate out-of-focus light, allowing for high-resolution, three-dimensional reconstructions of fluorescently labeled specimens. source
Which microscope demonstrates specimens as bright objects on a dark background without staining?
Phase-contrast microscope
Bright-field microscope
Fluorescence microscope
Dark-field microscope
Dark-field microscopy illuminates specimens at an oblique angle so only scattered light enters the objective, producing bright images on a dark background. It is useful for live, unstained samples like spirochetes. source
A light microscope with a numerical aperture (NA) of 1.25 and using green light (550 nm) has an approximate resolution limit of:
440 nm
550 nm
220 nm
110 nm
Using Abbe's equation (d=?/(2NA)), resolution d = 550 nm/(2×1.25) ? 220 nm, but realistic resolving power is about half that value, or ~110 nm, under ideal conditions. This illustrates the limitations of light microscopy. source
On a photomicrograph, a bacterium measures 5 mm long at 1000× magnification. What is its actual length?
500 µm
5 µm
0.5 µm
50 µm
Actual size = measured size / magnification. So 5 mm / 1000 = 0.005 mm = 5 µm. This conversion is key for interpreting microscopy images. source
Negative staining using India ink is commonly used to visualize:
Cell walls
Flagella
Capsules
Endospores
Negative staining stains the background, leaving capsules as clear halos around cells because the capsule repels most dyes. It's often used for organisms like Cryptococcus. source
Which filter pore size would remove most bacteria but allow viruses to pass through?
20 µm
0.2 µm
2 µm
0.02 µm
A 0.2 µm filter removes most bacteria (which are larger than 0.2 µm) but not viruses, which are typically <0.2 µm. This principle is used in virus preparation. source
Which microscopy technique offers the highest resolving power?
Phase-contrast microscopy
Transmission electron microscopy
Confocal microscopy
Scanning electron microscopy
Transmission electron microscopy (TEM) achieves resolutions down to 0.2 nm by transmitting electrons through ultrathin specimens, exceeding SEM, confocal, and phase-contrast capabilities. source
Cryo-electron microscopy is important because it:
Requires heavy metal staining for contrast
Images wet specimens at room temperature
Uses infrared light for deeper tissue penetration
Preserves native hydrated structures by rapid freezing
Cryo-EM rapidly freezes specimens, preserving their native, hydrated state without chemical fixation or staining. This allows near-atomic resolution structures of macromolecules. source
In phase-contrast microscopy, contrast is generated by:
Fluorescent dyes binding to molecules
Direct detection of scattered electrons
Use of oblique illumination only
Differences in refractive index converting phase shifts to amplitude changes
Phase-contrast microscopy converts phase shifts of light passing through transparent specimens into changes in brightness, enhancing contrast without staining. It exploits differences in refractive index. source
An 80 kV electron beam has a wavelength of roughly:
50 nm
0.5 nm
5 nm
0.005 nm
At 80 kV acceleration voltage, electron wavelengths are on the order of 0.005 nm (5 pm), enabling extremely high resolution in TEM. This is derived from de Broglie's wavelength equation. source
Which conversion is correct for 0.2 µm into nanometers?
200 nm
20 nm
2 nm
2000 nm
1 µm equals 1000 nm, so 0.2 µm equals 0.2×1000 nm = 200 nm. This conversion is fundamental when comparing light and electron microscopy scales. source
Which statement about ultrastructure visualization is correct?
Phase-contrast is used for atomic-scale imaging
Light microscopy can resolve ribosomes clearly
TEM requires ultrathin sections for internal detail
SEM images internal cell compartments by transmitted electrons
TEM uses ultrathin sections (50 - 100 nm) so electrons can pass through and reveal internal ultrastructure like ribosomes and membranes. Light and phase-contrast microscopy lack this resolution. source
Which technique can achieve single-molecule resolution in aqueous environments?
Phase-contrast microscopy
Scanning electron microscopy
Standard light microscopy
Atomic force microscopy
Atomic force microscopy (AFM) can image individual molecules in liquid at sub-nanometer resolution by scanning a fine probe over the sample surface. It doesn't rely on light or electrons. source
Which method is best for determining viral particle morphology at atomic resolution?
Confocal microscopy
Cryo-electron microscopy
Phase-contrast microscopy
Dark-field microscopy
Cryo-EM can resolve structures at near-atomic resolution by freezing particles in vitreous ice and imaging thousands of particles to reconstruct high-resolution models. source
Which wavelength of light provides the greatest theoretical resolution in optical microscopy?
700 nm (red light)
250 nm (UV light)
400 nm (violet light)
550 nm (green light)
Shorter wavelengths yield better resolution based on Abbe's equation. Among visible light, violet (around 400 nm) gives the highest theoretical resolution. UV can be better but requires specialized optics. source
Approximately how many times larger is an E. coli cell (2 µm) than a poliovirus particle (30 nm)?
?150×
?15×
?200×
?67×
Divide the sizes: 2 µm (2000 nm) ÷ 30 nm ? 67. This calculation illustrates scale differences between bacteria and viruses. source
Phase-contrast microscopy is most advantageous for viewing:
Dead, stained bacterial smears
Fluorescently labeled proteins
Live, unstained cells exhibiting internal structures
Surface topology of metal
Phase-contrast enhances contrast in transparent, live specimens without staining by converting phase shifts into brightness changes, making internal structures visible. source
Dark-field microscopy is especially useful for observing:
Fluorescent dyes
Spirochetes and motile bacteria without staining
Internal organelles of eukaryotes
High-contrast stained sections
Dark-field microscopy makes unstained motile organisms like spirochetes appear bright against a dark background, allowing visualization of live samples. source
Which parameter gives the greatest depth of field in microscopy?
High magnification
Small aperture diaphragm
Using oil immersion
High numerical aperture
A smaller aperture diaphragm increases depth of field, allowing more of the specimen's vertical plane to be in focus, though it may reduce resolution. source
Atomic force microscopy differs from electron microscopy because it:
Requires specimen to be in vacuum
Uses electron beams for surface imaging
Scans a physical probe over the surface to map topography
Relies on phase-shift of light passing through specimen
AFM uses a nanoscale probe that physically moves over a specimen to detect forces and map surface topography at atomic resolution, without the need for vacuum or electron beams. source
0
{"name":"What is the typical diameter of Escherichia coli?", "url":"https://www.quiz-maker.com/QPREVIEW","txt":"What is the typical diameter of Escherichia coli?, Which unit is most appropriate for measuring viral particles?, The typical size range for prokaryotic cells is:","img":"https://www.quiz-maker.com/3012/images/ogquiz.png"}

Study Outcomes

  1. Understand Microbial Size Scales -

    Learn to recognize and compare the size ranges of viruses, bacteria, and eukaryotic cells using appropriate metric units.

  2. Differentiate Between Virus, Bacterial, and Eukaryotic Dimensions -

    Identify key structural differences by comparing average sizes and morphologies of various microorganisms.

  3. Calculate Magnification and Actual Cell Sizes -

    Apply formulas to convert between image size, actual specimen size, and magnification in microscopy analyses.

  4. Apply Metric Unit Conversions for Microscopy -

    Practice converting measurements between nanometers, micrometers, and millimeters to improve accuracy in size determinations.

  5. Analyze Microscopy Images Using Scale Bars -

    Interpret scale bars on micrographs to determine real-world dimensions of microorganisms in study images.

  6. Evaluate Your Knowledge with Instant Scoring -

    Test your understanding through a quiz format that provides immediate feedback on chapter 3 microbiology questions.

Cheat Sheet

  1. Metric Prefixes & Orders of Magnitude -

    Remember the mnemonic "King Henry Died By Drinking Chocolate Milk" to recall kilo (10^3) down to milli (10^-3) when tackling microbiology test 3 conversions. Recognizing that viruses (~20 - 300 nm), bacteria (~0.5 - 5 µm), and eukaryotic cells (~10 - 100 µm) each occupy different scales helps you ace the microbiology chapter 3 quizlet on size. Practice converting 0.02 mm to micrometers (20 µm) to build confidence.

  2. Magnification Formula -

    Use the simple formula Total Magnification = Objective Lens × Eyepiece; for example, a 40× objective with a 10× eyepiece yields 400× in a light microscope. Always calibrate your measurements with a stage micrometer to ensure accurate size estimations. This tip is key for many cell magnification quiz questions in chapter 3 microbiology questions.

  3. Size Comparison: Viruses vs. Bacteria vs. Cells -

    Viruses measure in nanometers (20 - 300 nm), bacteria in micrometers (0.5 - 5 µm), and typical eukaryotic cells reach 10 - 100 µm, so visualizing these scales is crucial for the virus bacteria size quiz. Think of a virus as a grain of salt, a bacterium as a grain of sand, and an animal cell as a sesame seed to anchor these concepts. Practice drawing these scales side by side to embed the differences.

  4. Scientific Notation & Unit Conversions -

    Master converting sizes with scientific notation, such as converting 2.5 × 10^4 nm to 25 µm by dividing by 10^3, which frequently appears in chapter 3 microbiology questions. Writing numbers like this reduces errors when comparing microscopic dimensions in your microbiology test 3. Use flashcards to drill nm-to-µm and µm-to-mm conversions until they become second nature.

  5. Resolution Limits of Microscopy -

    Remember that standard light microscopes resolve down to ~200 nm while electron microscopes can reach ~1 nm, meaning viruses typically require electron microscopy to visualize. This fact is often tested in cell magnification quiz questions - know which tool fits each scale. Use a quick checklist: light for bacteria and cells, electron for viruses, to ensure you hit the right answer every time.

Make a Quiz (FREE) Copy & Edit This Quiz Create a Quiz with AI

Biology Quizzes

Powered by: Quiz Maker