UNIVERSITI TEKNOLOGI MARA (UiTM),

CAWANGAN PAHANG, KAMPUS JENGKA

BIO 122

HISTOLOGY OF CELL
AND TISSUE
(Experiment 1: Microscopy and the Cells)

OBJECTIVE PROCEDURE RESULTS DISCUSSION CONCLUSION TOTAL

OBJECTIVES
1. To describe the parts and functions of the compound light and dissecting microscope.
2. To learn about proper order to focus the cell’s image with a compound light microscope.
3. To calculate the diameter of the field and total magnification of the cell’s image.
4. To identify the differences between prokaryotic and eukaryotic cells.
5. To identify the differences between animal and plant cells.
 Eye piece

MATERIALS

1. Compound light microscope

2. Dissecting microscope
3. Slides

PROCEDURE
1. The microscope’s lens and the stage were cleaned up with clean wet tissue.
2. The prepared slide was placed on the stage of the microscope.
3. The light was switched on and the light intensity was set up to 4 or 5.
4. The coarse adjustment knob was rotated slowly to level up the stage.
5. The image was focused by adjusting the fine adjustment knob. Image of 4 times magnification was
formed.
6. Magnification was increased to 10 times magnification and the fine focus adjustment knob was
rotated to focus the image.
7. Image of 10 times magnification was formed.
8. Magnification was increased to 40 times magnification and the image had been viewed.
9. The objective lens slowly rotated to 100 times magnification.
10. A drop of immersion oil was placed onto the slide and the diaphragm has been used to adjust the
light to make the image became brighter.
11. The clear image has been viewed.

RESULT
1)

Compound light microscope

 Eye piece

Course adjustment Body tube

Diopter
knob
Nose piece
Stereo head
Fine adjustment
knob Zoom knob Objective
lens
Focus knob
Objective lens Clip
Light switch
Stage
Arm
Arm
Condenser
Clip
Bottom light
Iris diaphragm
Stage plate
Mirror Base

Base

Dissecting microscope

2)

Bacterial Cell
 Bacteria cell (Magnification, 100x)

3)

Plant Cell
Onion root tip cell (Magnification, 100x)
 Animal Cell

Cheek smear cell (Magnification, 100x)

4) Complete the following table:

Onion root tip cell

Magnification of Magnification of Magnification of Diameter of Field

Objectives Eyepiece Cell’s Image

4x 10x 40x 240µ

10x 10x 100x 130µm

40x 10x 400x 16µm

DISCUSSION I
Compound microscopes in the 1830s were made in lens quality that is eyepiece lens and objective
lens. The combination of improved microscopes led to an understanding of cell biological
organization (Hardin, Bertoni, & J. Kleinsmith, 2016). A compound microscope is the most common
type of microscope, contains several parts with a specific function. Each part of the microscope has
its role to make the microscope function as explained in the result. The total magnification of an
image can be calculated by multiplying the magnification of the objective lens by the magnification
of the ocular lens. For example, the magnification of the ocular lens is usually 10x, while the
magnification of the objective lens is 40x. To get the total magnification is, 10x multiply by 40x
which the answer is 400x. So the total magnification is 400x. The standard objective lenses fixed on
the turret of the microscope are 4x, 10x, 40x and 100x objectives. The 4x, 10x and 40x lenses are
collectively known as the dry lens. The exception of 100x objective is known as oil immersion as it
requires the use of immersion oil because you cannot use an immersion lens without oil. Never get
oil on any other lenses. When you already use the 100x objective, you cannot turn back to use 4x,
10x and 40x. We must not forget to clean up all oil when finished using wet wipes.

A stereo or dissecting microscope is a type of optical microscope that allows the user to see a three-
dimensional view of a specimen. Otherwise known as a dissecting microscope or stereo zoom
microscope, the stereo microscope differs from the compound light microscope by having separate
objective lenses and eyepieces. This results in two separate optical paths for each eye. Three-
dimensional visuals are produced by the different angling views for the left and right eye. Stereo
microscopes use reflected light from the object being studied, compared to the transmitted light that
is used by compound light microscopes. Magnification ranges from 7.5 to 75x. Opaque, thick, solid
objects are ideal for study with these tools. Most, but not all, stereo microscopes have two light
sources: one above the sample, which is reflected in the eyepieces, and one below the sample for
illumination through thinner samples. Resolution is determined by the wavelength of light and
numerical aperture of the objective, the same as any other form of optical light microscopy.

A compound microscope and dissecting microscope were different in application. A

compound microscope is used to observe ultra-thin pieces of larger objects. Examples could be the
stem of a plant or a cross-section of a human blood vessel. In both cases, the specimen is not living.
The piece is placed on a slide and stained with dyes to highlight features. While a dissecting
microscope can be used for items that light cannot shine through. The actual colours of the specimen
will be observed, and the specimen can be manipulated by the observer while being viewed. The
intricacy of butterfly wings, the detail of a scorpion claw and the weave in a piece of fabric are a few
examples of items that could be viewed. A dissecting microscope also might be used to observe some
living organisms such as those in pond water.
Compound microscope

PARTS OF FUNCTION
MICROSCOPE
Arm Supports the tube and connects it to the base
Base The bottom of the microscope, used for support.
Clip Stage clips hold the slides in place
Stage The flat platform where the slide is placed
Mirror Reflect light from an external source up through the bottom of the
stage
Eyepiece The lens at the top that the viewers look through to see the
specimen
Body tube Connects the eyepiece to the objective lenses
Condenser Gathers and focuses light from the mirror onto the specimen
viewed
Nose piece A rotating turret that houses the objective lenses
Objective lens The lenses closest to the specimen
Iris diaphragm Adjusts the amount of light that reaches the specimen
Fine adjustment knob Fine-tunes the focus and increases the detail of the specimen
Coarse adjustment Focuses the specimen on the microscope under low or medium
knob power by using larger motions of lens

Dissecting microscope

PARTS OF FUNCTION
MICROSCOPE
Arm Supports the tube and connects it to the base
Base Supports the microscope and it’s where the illuminator located
Diopter Change focus on one eyepiece to correct for any difference in
vision between the viewer’s two eyes
Stage plate The specimen is placed on the stage plate for viewing
Objective lens Consists of the different objective lens with different
magnification powers.
Body tube Connects the eyepiece to the objective lens.
Light switch Turns the light on or off.

Eyepiece Two eyepieces each focusing different pathways of the light into
and out of the specimen, each with its magnification power. To
increase the magnification, the use of auxiliary eyepieces can be
used.
Stereo head Carry the optical parts in the upper part of the microscope.
Bottom light Transmitted up through the stage to highlight translucent objects
Focus knob Moves the head portion of the microscope up and down to make
the image clear.
Zoom knob Zoom in on to a particular area of interest on the field of view to
get a closer look
DISCUSSION II

The cell is the smallest unit that possesses all seven attributes of life, therefore it is considered the
basic unit of life. All organisms are composed of one or more cells and arise from pre-existing cells.
Based on the experiment above, some experiments had been done on both prokaryotic and eukaryotic
cells. As for the prokaryotic cell, the experiments use the bacteria cells. From the observation, the
bacteria cells contain a cell wall, cytoplasm, cell membrane but no nucleus is seen. The cell walls of
the prokaryotic cells are mainly from peptidoglycan where it gave the cell a fixed shape. The
cytoplasm helps maintain the shape of the cells. There was another example for prokaryotic which is
called photosynthetic bacteria like Cyanobacteria. The bacteria cells do contain chloroplast that is
scattered in the cytoplasm. The chloroplast of the bacteria cells provides energy driving the
photosynthesis process in the presence of sunlight. The biggest distinction between them is that
eukaryotic cells have a distinct nucleus containing the cell's genetic material, while prokaryotic cells
don't have a nucleus and have free-floating genetic material. Another important difference is the
DNA structure. Eukaryote DNA consists of multiple molecules of double-stranded linear DNA,
while that of prokaryotes is double-stranded and circular

As for eukaryotic cells, the experiments had been done on animal and plant cells. For animal cells,
use cheek smear cells had been used as the models. The experiment found out that the cheek cells
contain a plasma membrane, a visible nucleus, and some dot-like that might be the organelles. While
for the plant cells, onion root tip cells had been used. From the observation, we found that plant cells
have all the composition that present in animal cells, but plant cells like onion cells do not compose
chloroplast while another example of a plant cell was Elodea sp. composed of cell wall and
chloroplast. The plasma membrane gives protection for the cells from the outsiders to get in easily.
The nucleus control all the process of the whole cells. The chloroplast provides energy by undergoing
photosynthesis. For a cell that does not have chloroplast like an animal cell, the cell depends on
mitochondria to generate energy. The cell wall of the plant cell which is made from cellulose helps
strengthen the cells. Both animal and plant cells have mitochondria, but only plant cells have
chloroplasts. Plants don’t get their sugar from eating food, so they need to make sugar from sunlight.
This process (photosynthesis) takes place in the chloroplast. Once the sugar is made, it is then broken
down by the mitochondria to make energy for the cell. Because animals get sugar from the food they
eat, they do not need chloroplasts: just mitochondria. Both plant and animal cells have vacuoles. A
plant cell contains a large, singular vacuole that is used for storage and maintaining the shape of the
cell. In contrast, animal cells have many, smaller vacuoles. Plant cells have a cell wall, as well as a
cell membrane. In plants, the cell wall surrounds the cell membrane. This gives the plant cell its
unique rectangular shape. Animal cells simply have a cell membrane, but no cell wall.
Conclusion
In conclusion, identifying every part of the microscope is essential to handle and use the microscope
properly. Every part of the microscope needs to be recognized so that it would make every
experiment easier when using a microscope to observe any sample or specimen. The bacterial cell,
plant cell and animal cell observed had shown the difference in the structure and shapes. Experiments
to focus onion root tip cell’s image with a compound microscope have been carried out. The diameter
of the field for 4x magnification is 240µ, 10x magnification is 130µ and 40x magnification is 16µ.
The differences between eukaryotic and prokaryotic cells had been observed. Based on the
experiment, prokaryotic cells are an organism that has neither nucleus nor organelles whereas
eukaryotic cells are an organism that has a nucleus as well the organelle. The differences of the same
group of plant cells that certain plant cells have chloroplast like Elodea sp. and some not like onion
cells. As a conclusion, we can conclude that every cell has its special characteristic that allows them
to survive until now. The big difference between plant and animal cells in the structural differences.
Plant cells are rectangular but animal cells are round in shape. Besides, plant cells contain vacuoles,
cell wall, chloroplast while animal cells do not.
 References

1) https://www.amscope.com/blog/compound-vs-stereo-microscopes/#:~:text=A
%20compound%20microscope%20is%20commonly,small%20electronic
%20components%20or%20stamps.
2) https://www.thoughtco.com/what-are-prokaryotes-and-eukaryotes-
129478#:~:text=Prokaryotes%20are%20organisms%20made%20up,well%20as
%20membrane%2Dbound%20organelles.
3) https://byjus.com/biology/difference-between-plant-animal-bacterial-cells/
4) https://www.microscopemaster.com/parts-of-a-compound-
microscope.html#:~:text=First%2C%20the%20purpose%20of%20a,seen%20by
%20the%20naked%20eye.
5) Online Campbell book,
https://drive.google.com/file/d/1bpJzapnu2k4MraxDtBPWw7ubfDr7z09s/view?
usp=drivesdk

Thank You