1. BIOLOGY FORM 1
LESSON NOTES
RESEARCH SKILLS
By
Frank George Mgungwe
Malomo Community Day Secondary School
2. Research Skills
Investigative techniques
The term ‘Biology’ is derived from two Greek
words: Bios meaning life and logos meaning
study. Therefore Biology is the study of living
things.
Safety measures in the laboratory
These are set of instructions that ensure
proper use of the laboratory facilities
and safety to all laboratory users. These
include:
1. Never run or play in the laboratory.
2. Do not eat or taste anything in the
laboratory.
3. Safety measures in the laboratory
3. Do not carry out any activity in the
laboratory before you are told to do
so.
4. Always turn off the gas and water
taps after use.
5. Wash all equipment after use.
6. Follow experimental procedures.
7. Do not use chemicals before you
are told to use them.
8. Ensure that the laboratory is well
4. Safety measures in the laboratory
9. Dispose off any broken apparatus carefully.
10. Sterilize culture before disposal or
incineration.
11. Wash hands before and after practical
sessions with detergents.
12. Wear goggles and face masks when
handling toxic substances.
13. Wipe spills as soon as they occur.
14. Wear closed shoes in the laboratory.
15. Tuck in your uniform and hold your tie by
the waist.
5. Consequences of failure to follow
laboratory rules
Injury or death of an individual due to:
i. Diseases contracted from specimens being
handled.
ii. Inhaling poisonous fumes.
iii. Being cut by the sharp object.
iv. Eyes being hurt by broken pieces of glass
or scalpel.
v. Scalding by hot liquids or vapour.
vi. Being bitten by spiders, snakes or being
stung by bees or scorpions.
6. Handling of accidents
a. Report any injury to a teacher however
minor.
b. Provide first aid if possible.
c. Treat a client who has suffocated on an
open air where there is plenty of fresh air.
d. Cover the injured part with a clean
bandage.
e. Avoid contact with blood of a patient by
wearing gloves to avoid blood-borne
diseases.
7. Safe use of apparatus
Glassware: These are materials made up of
glass. Examples: beakers, test tubes, measuring
cylinder, pipettes, conical flasks, volumetric
flasks and aquariums.
Rules for using glassware safely
1. Do not use them for carrying food or drink.
2. They have to be well fastened to racks to
avoid falling down or rolling.
3. Place soft material between glassware and a
metal during a clamping.
4. Use tongs to hold hot glassware.
5. Do not store glassware together with metals.
6. Never use chipped glassware.
7. Clean them after use.
8. Burners
Burners are used for heating substances
when doing practical work. Examples are
Bunsen burners, spirit burners or gas burner,
stoves, and wick lump.
Rules for using burners safely:
1. Always turn off gas taps after doing an
experiment.
2. Follow correct procedure when lighting a burner.
3. Boiling tubes should never be filled up to the
brim to avoid overflowing of the liquids being
heated which could cause fire.
4. Heat flammable substances such as ethanol in a
water bath to avoid catching fire.
5. Heat flasks or beakers while placed on the wire
gauze.
14. The microscope
A microscope is an instrument for observing
and magnifying organisms that are too tiny to
be seen by our naked eyes.
There are two types of microscopes:
1. Light microscope.
- This uses light to illuminate the objects and
glass lenses to magnify the object.
2. Electron microscope.
- This uses a beam of electrons to magnify
an object. It is very powerful as compared to
the light microscope due to high contrast and
resolution power.
18. Parts of the light microscope
1. Eye piece
- Used for magnifying an object.
2. Body tube
- Holds the eye piece and revolving nose piece
in position.
- Allows light from the specimen to pass to the
observer.
3. Course adjustment knob
- For moving the body tube up and down to give
a clear view of the image.
4. Fine adjustment knobs
- Used to bring the object into sharp focus.
19. Parts of the light microscope …
5. Objective lenses
- Used to magnify the specimen further.
- There are three types of lenses:
i. Low power lens – a lens that magnifies an
object 4 -5 times.
ii. Medium power lens – magnifies an object
10 times.
iii. High power lens – this has a magnification
of 60 times or more.
20. Parts of the light microscope
6. Revolving nose piece - Holds the objective lens in
position.
7. Mirror - Reflects light to the specimen from the source.
8. Stage: It holds the slide in position.
9. Condenser - It receives light from the mirror and then
concentrates it on the specimen on the stage.
10. Diaphragm- It controls the amount of light from the
source to pass through the condenser.
11. Clips- Hold the slide intact on the stage for viewing.
12. Arm - Supports the body tube - Used as a handle for
lifting the microscope.
13. Stand or base - It supports the microscope to stand.
21. Observing a specimen on a microscope
- Specimen to be observed is placed on the
slide and it is covered by a cover slip.
- Then place the slide on the stage.
- One eye should be directly above the eye
piece.
- Start to view the slide using low power
objectives, then medium power and finally
high power objectives lens.
- Focus your specimen using coarse
adjustment knob.
- - Fine tune the visibility of the specimen
by using fine adjustment knob.
- - Orient the mirror to bring more light on
to the stage.
22. Mounting a specimen on the
slide
- Add a specimen on a clean slide.
- Place the sample in the centre of
the slide and add a drop of water.
- Cover the specimen with a cover
slip to protect the lens from liquids.
23. Magnification
Magnification
- This is how much the object has been
enlarged or reduced. It is the increase or
decrease of an object’s apparent size. It is
calculated using the formula:
Magnification =
𝑙𝑒𝑛𝑔𝑡ℎ 𝑜𝑓 𝑑𝑟𝑎𝑤𝑖𝑛𝑔
𝑙𝑒𝑛𝑔𝑡ℎ 𝑜𝑓 𝑠𝑝𝑒𝑐𝑖𝑚𝑒𝑛
When the size of the drawing is bigger
than the size of the specimen,
magnification is a whole number e.g. x2.
This means an object has been increased
by two times.
24. Magnification
• Magnification is calculated using the
following equation:
Magnification = Drawing size ÷ Actual
size
A better way to remember the
equation is using an equation triangle:
25. Magnification
Rearranging the equation to find things
other than the magnification becomes
easy when you remember the triangle –
whatever you are trying to find,
place your finger over it and
whatever is left is what you do, so:
• Magnification = image size / actual size
• Actual size = image size / magnification
• Image size = magnification x actual size
26. Worked example
An image of an animal cell is 30 mm in
size and it has been magnified by a
factor of X 3000. What is the actual size
of the cell?
To find the actual size of the cell:
27. Magnification
When size of the drawing is smaller than the
size of the specimen, magnification is a
fraction e.g. X
1
2
or X 0.5. This means that the
object has been reduced by half.
NB: Magnification has no units.
28. Magnification
Whatever you are trying to find,
place your finger over it and
whatever is left is what you do, so:
• Magnification = image size / actual size
• Actual size = image size / magnification
• Image size = magnification x actual size
29. Resolution of Microscope
The ability to see greater detail in an
image depends on the resolution or
resolving power. This is the ability to see
two points as two points, rather than
merged into one.
In microscopy, the term ‘resolution’ is
used to describe the ability of a
microscope to distinguish detail.
In other words, this is the minimum
distance at which two distinct points of a
specimen can still be seen - either by the
observer or the microscope camera - as
30. Field of View
Field of View is the Area
seen when looking through
the Microscope
31. Calculating Magnification:
Example
Assume that the Magnification of
eyepiece is x10, calculate the total
Magnification hen you view a sample
under the microscope using the
following objective lenses:
a) x4 b.) x10 c) x40
Solution:
32. Units of measurements
Since the establishment of the
International System of units (SI unit) in
1960, there is only a single unit
acceptable throughout the world for
some measurements.
Measurement Symbol SI unit
Length m Metre
Mass kg Kilogram
Time s Second
Temperature ℃ Degrees celsius
33. Units of measurements
1. Length:This is distance covered by
something. It is measured by a rule or tape
measure in metres.
2. Mass: This is quantity of matter in an
object. It can be taken using a triple beam
balance.
3. Force: It is a push or pull. It is
measured by a spring balance in Newtons
34. Units of measurements
4. Time - This can be measured using a stop
watch in seconds. Evolution is measured on a
time scale
5. Temperature: It is measured using a
thermometer in degrees Celsius. Ordinary
temperature is measured by an ordinary
thermometer while body temperature is
measured by a clinical thermometer.
35. Units of measurements
6. Volume: Volume of liquids is measured
using a measuring cylinder, beaker,
volumetric flask, burette, a syringe in cubic
millimeters (mm3), cubic centimetres (cm3),
litres (l), and milliliters (ml).
SI unit for measuring volume of liquids is a
litre (l).
1 l = 1000ml or 1000cm3
1 l = 1dm
Volume of regular solids is calculated
using the formula: L X B X H
36. Units of measurements
Area: This is the surface covered by an
object.
It can be calculated using various
formulas depending on shape of the
surface e.g. Area of rectangle = L X B
Area of irregular
Shaped object eg
Area of a leaf: Use a
square graph like this
37. Study skills in learning science
A skill is ability of doing something. One
of the skills that a student acquires at
school is how to read with understanding.
You can check your understanding by
rewriting what you have read in your own
words or summarizing the information.
For us to understand what we read we
need to know the following study skills:
1. Ways of summarizing information from
a reading or secondary source.
2. Judging statements.
