Microscopes Flashcards
(20 cards)
Who is credited with the invention of the first compound microscope?
Dutch spectacle makers Janssen in the 1590s
Janssen experimented with putting lenses in tubes to create the first compound microscope.
What is the estimated magnification range of the first compound microscopes made by Janssen?
×3 to ×9
This range refers to the magnification capability of the early compound microscopes.
What significant observation did Robert Hooke make with a compound microscope in 1650?
He observed and drew cells
Hooke is also known for his law of elasticity in Physics.
What was the maximum magnification achieved by Antonie van Leeuwenhoek’s microscope in the late 1600s?
×275
Van Leeuwenhoek’s microscope featured a single spherical lens.
In what century did Antonie van Leeuwenhoek construct his microscope?
17th century
This period marks significant advances in microscopy.
How did the optical quality of lenses change in the 1800s?
It increased, making microscopes similar to those used today
This improvement contributed to the overall advancement of microscopy.
What is the maximum magnification possible with a light microscope?
Around ×1500
Despite advancements, very high magnifications remain unattainable with light microscopes.
Fill in the blank: The first compound microscope was made by _______ in the 1590s.
Dutch spectacle makers Janssen
True or False: Robert Hooke was the first to use a microscope to observe cells.
True
Hooke’s observations were groundbreaking in the study of biology.
What key advancement occurred in the development of microscopes in the 1800s?
Improved optical quality of lenses
This led to microscopes that closely resemble modern designs.
What is the definition of resolution in microscopy?
The ability to see two points as two points, rather than merged into one.
Resolution is crucial for observing fine details in specimens.
What is the resolution of a light microscope?
Around 0.2 μm, or 200 nm.
This means it cannot distinguish two points closer than 200 nm.
How is one nanometre (nm) defined?
One billionth of a metre, or 1 × 10^-9 m.
Nanometres are commonly used in measuring wavelengths and sizes at the molecular level.
What type of microscope uses a beam of electrons instead of light rays?
Electron microscope.
Electron microscopes provide much higher resolution compared to light microscopes.
What is the primary use of a scanning electron microscope (SEM)?
To examine the surface structure of specimens.
SEMs are typically used at lower magnifications.
What does a transmission electron microscope (TEM) examine?
Thin slices or sections of cells or tissues.
TEMs allow for detailed internal structure observation.
What is the maximum magnification of a transmission electron microscope (TEM)?
Around ×1,000,000.
Images can be enlarged beyond this limit photographically.
What is the limit of resolution of the transmission electron microscope?
Less than 1 nm.
This high resolution allows visualization of structures not visible with light microscopes.
True or False: The detail seen in a microscope image is solely dependent on magnification.
False.
Both magnification and resolution are important for viewing details.
Fill in the blank: The resolution of a light microscope is around _____ μm.
0.2
This resolution limits the ability to distinguish very close points.
