Lesson 2 Flashcards
A magnifying glass used to magnify an object to a point where it can be seen by the human eye.
Microscope
The science of investigating small objects and structures using such an instrument.
Microscopy
Means invisible to the eye unless aided by a microscope
Microscopic
The art of ____ is developed in Italy and _______ are made to improve eyesight.
What year?
14th Century
- grinding lenses
- spectacles
Dutch lens grinders _____ and ______ make the first microscope by placing two lenses in a tube.
What year?
1590
-Hans and Zacharias Janssen
____ studies various object with his microscope and publishes his results in ___. Among his work was a description of ____ and ____.
What year?
1667
- Robert Hooke
- Micrographia
- cork and its ability to float in water
______ (Father of _____) uses a
simple microscope with only one lens to look at blood, insects and many other objects. He was first to describe _____, seen through his very small microscopes with, for his time, extremely good lenses.
What year?
1675
- Anton van Leeuwenhoek
- Microscopy
- cells and bacteria
Several technical innovations make microscopes better and easier to handle, which leads to microscopy becoming more and more popular among scientists.
An important discovery is that lenses
combining two types of glass could reduce the ______, with its disturbing halos resulting from differences in refraction of light.
What year?
18th Century
- chromatic effect
Reduces the problem with_______ by showing that several weak lenses used together at certain distances gave good magnification
without blurring the image.
What year?
1830
- Joseph Jackson Lister
- spherical aberration
The three structural parts of the microscope and its function.
Head - it carries the optical parts in the upper part of the microscope
Base - it acts as the microscope’s support; it also carries the microscopic illuminators
Arms - the part that connects the base to the head and the eyepiece tube to the base of the microscope; it gives support to the head and used when carrying the microscope
Usually equipped with _____lenses. The lenses magnify the intermediate image formed by the objective lens in the optical tube. They also limit the area of visibility
Eyepiece or oculars
- 10x
Prevents scratching of lens by the user’s eyeglass or vice versa
Eyepiece rubbers
For differences in eye grading especially for those wearing prescription glasses
Numbers on the eyepiece
Used to adjust the lateral separation of the oculars for each individual
Interpupillary control
Provides a structural site of attachment for the revolving nosepiece.
Arm or neck
Holds the objectives and allows for easy rotation from one objective to another
Revolving nosepiece
Controls the height limit of the stage to prevent breakage of glass slides
____ – to tighten the screw
____ – to loosen the screw
Knob/screw at the back of the microscope
- Clockwise
- Counterclockwise
Also known as the coarse tension adjustment knob
Prevents the stage from going down and losing focus on the specimen
____ - to tighten
____ - to loosen
Inner knob before the coarse adjustment knob
- Clockwise
-Counterclockwise
Refers to the thickness of the coverslip to be used; coverslip to be used must be compatible with the objective to be used for microscopic examination
Numbers on the objectives
Most objectives have 3 to 4 lenses. What are the objectives and their corresponding magnification?
Objectives
-Scanner Objective (4x)
-Low Power Objective (10x)
-High Power Objective (40x)
-Oil Immersion Objective (100x)
A hole on the microscope stage through which the transmitted light from
the source reaches the stage
Aperture
Supports the prepared microscope slide to be reviewed. Most have mechanical stage, which make it much easier to manipulate the object being observed
Mechanical stage
Also available by turning the knob left and right or backward and forward
Mechanical stage knob
Determines the positioning of the cells under the microscope; provides the coordinates or location of important cells
Stage numbers
