BIOLOGY 189 LAB 6 LIGHT MICROSCOPY AND CELL STRUCTURE

what is a microscope ?

a piece of equipment that makes it possible to study and explore specimens that are small to view with the human eye.

microscope can be used to view what ?

characteristics of small organisms such as as the finer structural details of organs and tissues within in the human body and the bodies and cells of other organisms.

what is the type of microscope used in this lab called ?

compound light microscope

what do light microscope magnify? and using what?

magnify the image of the specimen using light and lenses

what does the term compound for a microscope mean?

means that a microscope passes light through the specimen and then through different lenses.

compound light microscopes are ?

parfocal

what does the term parfocal mean ?

means once an object is in focus using the scanning lens it will remain in coarse focus when the lenses are changed into a higher power.

at this point only the fine focus is needed in order to?

to get the clearest view.

what are ocular lenses?

they are lenses to look through to see a specimen. most have a magnification of 10x or 15x. many may obtains a pointer set in the glass which enables the viewer to point at parts of the specimen.

What is the head of the microscope?

the upper part of microscope containing oculars and rotating nose piece.

What is the arm of a microscope?

vertical part connecting the head and base it can be straight or curved supports the upper parts and provides a carrying handle

what is the rotating nose piece of a microscope?

located below the ocular lenses. an attachment for the 4 objective lenses which helps to rotate the nose piece to change from one objective lens to another.

what are the 4 objective lenses in a microscope?

-scanning lens
-low power lens
-high power lens
-oil immersion lens

what is the scanning lens of a microscope? there magnification? and use for?

they are the shortest of the objective lens, magnification is 4x, and used to scan the whole slide

what is the low power lens of a microscope? their magnification? and use for?

longer than the scanning lens, magnification is 10x, used to view objects in greater detail.

what is the high power lens of a microscope? their magnification? and used for?

longer than the low power lens , magnification of 40x is used to view objects in greater detail.

what is the oil immersion lens of a microscope? there magnification? and used for?

longer than the high power lens , magnification 100x, used in conjunction with immersion oil to view objects with the greatest magnification.

what is the mechanical stage/stage clip in a microscope?

the clips where it keeps the specimen slide stationary when seeing.

what is the mechanical stage/stage clip control in a microscope?

2 knobs that allows the movement of the specimen slide on the stage while viewing.

what is the stage in a microscope?

the flat platform connected to the arm and beneath the objective lenses which are the specimen slide is placed.

what is the condenser in a microscope?

a lens located below the stage that concentrates light on the specimen. father way the condenser is from the specimen the broad the light beam. closer the condenser to the specimen the more narrow and concentrated the light beam. the best position for the condenser is close to the stage.

What is the iris diaphragm of a microscope?

a lever located beneath the condenser it opens and closes the iris diaphragm regulating the light passing through the condenser

what is the condenser control of a microscope?

knob allowing the viewer to control the position of the condenser.

What is the coarse adjustment knob of a microscope and use for ?

a big knob on either side of microscope at the base of the arm. turning them can rise and lower the stage.it helps with focusing. this type of knob should only be used with the scanning lens (4x) or the low power lens (10x) to avoid contacting the objective lens with the specimen slide.

What is the fine adjustment knob of a microscope and used for?

a small knob on either side of the microscope at the base of the arm in the center of the coarse knob. used for precision focusing, since they raise or lower the stage in very small increments. safe to use with high power (40x) and oil immersion (100x) lenses.

what is the substage light of a microscope?

a light within the base that providing the light source for illumination of the specimen. a power switch usually at the side or front of the microscope turns it off and on.

what is the rheostat of a microscope?

a dial that adjusts the light intensity allowed through the condenser on to the specimen.

What is the base of a microscope?

the supportive flat surface of the microscope that rests on the table

what is another type of light microscope that is commonly used in biology called?

dissecting microscope

how is the total magnification calculated?

by multiplying the magnification of the ocular lens by the magnification of the objective lens

field or view or the total amount of the specimen that is visible will?

decrease any time an object is magnified so if the closer it is the more zoomed in it is causing to see part of it the more zoomed out it is the more full screen you can see.

cells come in 3 different things which are?

shapes, sizes, and functions

what are the 3 common characteristics of cells?

- the outer boundary of the cell is the PLASMA MEMBRANE
-all cells store genetic information in the form of DNA
-everything inside the plasma membrane that is not DNA or the nucleus is CYTOPLASM

cells are divided into 2 types based on their complexity of their internal structure which are 2 types?

prokaryotes and eukaryotic cells.

prokaryotes are____? where is there DNA? obtain any membrane-bound organelles? give 2 examples of prokaryotes?

less complex cells, DNA found in cytoplasm not in a nucleus, do not have membrane-bound, bacteria and cyanobacteria are examples

Eukaryotic cells are _____? what do they contain give 2 examples? where is there DNA stored in? give four examples of eukaryotes ?

are more highly organized, contain membrane -bound organelles such as mitochondria and chloroplasts, store DNA in the nucleus, 4 examples are protists, fungi, plants and animals.

what is the plasma membrane of a prokaryote cell?

phospholipid bilayer

what is the DNA of a prokaryote cell?

a single loop of a DNA not in a nucleus

what is the cytoplasm of prokaryote cell?

only structures are ribosome; some have short membranes segments to anchor photosynthetic pigments.

what is the kingdom of prokaryote cell?

eubacteria and archaebacteria

what is the plasma membrane of eukaryote cell?

phospholipid bilayer

what is the DNA of eukaryote cell?

more than one molecule of DNA enclosed in nucleus

what is the cytoplasm of eukaryote cell?

include ribosome and membrane -bound organelles with specific functions.

what is the kingdoms of eukaryote cells?

protista, fungi, plantae, Animalia

what are the 6 kingdoms all living organisms classified into?

monera (eubacteria and archaebacteria)
protista
fungi
plantae
Animalia

the kingdom miners (eurabacteria and archaebacteria) are?

unicellular prokaryotic organisms

kingdoms protista(protist), fungi(fungi), plantae(plants), and Animalia (animals) contain?

both unicellular and multicellular eukaryotic organisms

fungi and protist cells have similar structures to ?

plant and animal cells