ZOOLOGY LABORATORY 2 Flashcards
Often credited with creating the first
compound microscope, which used a
combination of lenses to magnify objects.
Hans and Zacharias Janssen (Late 16th century)
Developed a compound
microscope with a convex and
concave lens.
Galileo Galilei (late 17th century)
Known as the “Father of Microbiology”
• Made significant improvements to simple
microscopes, achieving magnifications of up
to 300 times.
Antonie Van Leeuwenhoek (17th century)
___ is the scientific
study of small objects using a
microscope. It involves the use of
various types of microscopes to
magnify objects that are too
small to be seen with the naked
eye, such as cells, bacteria, and
other microorganisms.
Microscopy
A ____ microscope is a laboratory instrument used to
magnify objects that are too small to be seen with the naked eye.
Compound
• _____ : The lens you look through to view the magnified
specimen.
• _____ lenses: A set of lenses with different magnification
powers (e.g., 4x, 10x, 40x, 100x).
• _____: A rotating mechanism that holds the objective lenses
and allows you to switch between them.
• ____: A lens system that focuses light onto the specimen.
• ____ diaphragm: A mechanism that controls the amount of light
passing through the condenser.
Eyepiece
Objective
Nosepiece
Condenser
Iris
• ____ : A platform that holds the specimen.
• ____ : Metal clips that secure the specimen in place.
• ____ : Coarse and fine adjustment knobs used to bring
the specimen into focus.
• ____: The main structural support of the microscope.
• ____: The bottom part of the microscope that provides stability
• ____: A built-in lamp or external light source that
provides illumination.
• ____: A mirror (in older models) that can be used to reflect
light from an external source onto the specimen.
Stage
Stage clips
Focus knobs
Arm
Base
Light source
Mirror
____ microscope
• Use visible light or UV light
• Brightfield, darkfield, Phase-contrast and fluorescent
____ microscope
• Use electron beams
Light
Electron
• Most common type.
• Image Formation: Light passes through
the specimen and is magnified by the
objective lenses.
• Applications: Suitable for observing
stained specimens, such as bacteria and
cells.
Brightfield microscope
• Image formation: Only light scattered by
the specimen enters the objective lens.
• Appearance: Unstained specimens
appear bright against a dark background.
• Applications: Ideal for observing
unstained transparent specimens, such as
living microorganisms.
Darkfield microscope
• Image formation: Converts differences in
refractive index within the specimen into
differences in brightness.
• Appearance: Provides a detailed view of
unstained living cells and tissues.
• Applications: Widely used in cell biology
and microbiology.
Phase contrast microscope
• Image formation: Detects light emitted by
fluorescent molecules within the specimen.
• Appearance: Fluorescent molecules appear
as brightly colored objects against a dark
background.
• Applications: Used for studying specific
molecules or structures within cells and
tissues.
Fluorescent microscope
• Image formation: A beam of electrons passes through a thin specimen
and is magnified by a series of lenses.
• Appearance: Provides a high-resolution image of the internal structure
of the specimen.
• Applications: Used to study the ultrastructure of cells, tissues, and
materials.
Transmission electron microscope (TEM)
• Image formation: A beam of electrons scans the surface of the
specimen and interacts with the atoms to produce secondary electrons.
• Appearance: Provides a detailed image of the surface topography of
the specimen.
• Applications: Used to study the surface features of materials, such as
metals, ceramics, and polymers.
Scanning electron microscope (SEM)
• Image formation: A beam of electrons scans the surface of the
specimen and interacts with the atoms to produce secondary electrons.
• Appearance: Provides a detailed image of the surface topography of
the specimen.
• Applications: Used to study the surface features of materials, such as
metals, ceramics, and polymers.
Scanning electron microscope (SEM)
