taibah university faculty of science and arts yanbu biology department course of general biology:...
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Taibah University
Faculty of Science and Arts
Yanbu
Biology Department
Course of General Biology:
Course teacher: Dr. Trabelsi Souad
Biology Lab 1-2
Complete Report Sheet
Start Lab
• Microscopy and Cytology
INSTRUCTIONS FOR LAB
This unit is divided into two parts; microscopy and cytology.
Complete the report sheet as you do your lab. Turn your completed report sheet in to your instructor.
This is a dry lab. You will not have to gather materials and can begin your lab immediately.
1 Discovery of cells
Bark
1665 Robert Hooke
Microscope
1 Discovery of cells
Take a piece of cork
1665 Robert Hooke
MicroscopeTake a piece of cork
1 Discovery of cells
Bark
Microscope
1665 Robert Hooke
Cork cells
1 Discovery of cells
In early 1800s, Schleiden, Schwann & Virchov suggested
In early 1800s, Schleiden, Schwann & Virchov suggested
1 Discovery of cells
The cell is the basic unit of structureand function in all living things
Three rules of cell theory :
Every cell originates from another preexisting cell
1 Discovery of cells
All living things consist of cells
2 Microscope
light microscope
light microscope
dissection microscopedissection
microscope
electron microscope
electron microscope
2 Microscope
Eyepiece
MagnificationMagnification
light microscope
Objective
2 Microscope
Body tube
Holds eyepiece & objectives
Holds eyepiece & objectiveslight
microscope
2 Microscope
can be rotated to bring the
objective into line
can be rotated to bring the
objective into line
light microscope
Revolving nosepiece
2 Microscope
Coarse adjustmen
t
light microscope
to raise or lower the body tube for
focusing
to raise or lower the body tube for
focusing
2 Microscope
supports the slide & allows the light to reach the specimen
supports the slide & allows the light to reach the specimen
Stage
light microscope
2 Microscope
holds the slide in position on the stage
holds the slide in position on the stage
Clip
light microscope
2 Microscope
reflects light from a light sourcereflects light from a light source
Mirror
light microscope
2 Microscope
regulates the amount of light passing through the condenser
regulates the amount of light passing through the condenser
light microscope
Iris diaphragm
2 Microscope
Arm
Base
light microscope
2 Microscope
2
3
4
5
6
7
8
9
10
1
arm
coarse adjustment
base
eyepiece
Summary light microscope
body tube
revolving nosepiece
objective
stage
iris diaphragm
mirror
2 Microscope
A. Low Power Observation
A. Low Power Observation
Experiment 3.1
Using a light microscope
2 Microscope
low power eyepieces
Low power observation
low power eyepieces into the top of the body tube
1. Insert the
2 Microscope
2. Adjust the mirror to reflect light through the hole in the stage
mirror
Low power observation
2 Microscope
3. Adjust the condenser & diaphragm to change the amount of light
condenser & iris diaphragm
Low power observation
2 Microscope
4. Select a low power objective
Low power observation
2 Microscope
5. Place the slide onto the stage
Low power observation
2 Microscope
6. Look through the eyepiece, carefully turn the coarse adjustment to lower the objective until the object is in focus
Low power observation
2 Microscope
7. Lower the objective just above the slide
Low power observation
2 Microscope
B. High Power Observation
B. High Power Observation
2 Microscope
1. Observe the specimen with low power first
1. Observe the specimen with low power first
High power observation
2 Microscope
2. Move the slide so that the part to be observed is at the centre of view
2. Move the slide so that the part to be observed is at the centre of view
3. Rotate the revolving nosepiece until 40X objective clicks into position
High power observation
2 Microscope
4. Adjust the fine adjustment only until the object is in focus
High power observation
2 Microscope
5. Adjust mirror, condenser & diaphragm to increase the light intensity
High power observation
2 Microscope
3 Basic structure of a cell
NucleusChloroplast
MitochondrionVacuole
Cell wall
Cell membrane
Cytoplasm
3 Basic structure of a cell
3 Basic structure of a cell
is made up of
Cellulose
Cell wall
Feature
Hard Protect & support
Large spaces between the
cellulose fibers
Allow large particles to penetrate the cell
wall
Cell wall
Function
3 Basic structure of a cell
NucleusChloroplast
MitochondrionVacuole
Cell wall
Cell membrane
Cytoplasm
3 Basic structure of a cell
Protein & lipid
consists of
the movement of materials in or out
of the cell
Control
3 Basic structure of a cell
Cell membrane
3 Basic structure of a cell
Cell membrane
is selectively permeable
the movement of materials in or out
of the cell
Control
NucleusChloroplast
MitochondrionVacuole
Cell wall
Cell membrane
Cytoplasm
3 Basic structure of a cell
an aqueous solution of many substances
e.g. protein
consists of
clear, jelly-like
provides a medium for
chemical reactions to take place
provides a medium for
chemical reactions to take place
3 Basic structure of a cell
Cytoplasm
contains a lot of organelles & granules
contains a lot of organelles & granules
NucleusChloroplast
MitochondrionVacuole
Cell wall
Cell membrane
Cytoplasm
3 Basic structure of a cell
3 Basic structure of a cell
Chloroplast
contains chlorophyll
contains chlorophyll
absorbs sunlight for
photosynthesis
absorbs sunlight for
photosynthesis
NucleusChloroplast
MitochondrionVacuole
Cell wall
Cell membrane
Cytoplasm
3 Basic structure of a cell
control activities of cell
contains chromosomes
made up of DNA
3 Basic structure of a cell
Nucleus
bounded by a nuclear membrane
NucleusChloroplast
MitochondrionVacuole
Cell wall
Cell membrane
Cytoplasm
3 Basic structure of a cell
Respiration takes place
release energy
3 Basic structure of a cell
Mitochondrion
NucleusChloroplast
MitochondrionVacuole
Cell wall
Cell membrane
Cytoplasm
3 Basic structure of a cell
provides support when it is fully filled with water
provides support when it is fully filled with water
large, at the centrelarge, at the centre
contains a solution of sugars, proteins
and minerals
contains a solution of sugars, proteins
and minerals
3 Basic structure of a cell
Vacuole
Difference ?
Plant Cell Animal Cell
no cell wall
no chloroplast
3 Basic structure of a cell
small vacuole
Cell membrane Nucleus
1. bounded by a nuclear membrane
2. contains chromosomes
Plant Cells
Cell wall (in plant
cells only)
SummaryAnimal Cells
3 Basic structure of a cell
Cytoplasm
2. non-living granules
e.g. starch(in plant cells only)
3. chloroplast (in plant cells only)
1. mitochondria
e.g. glycogen (in animal cells only)
4 The similarities and differencesbetween plant and animal cells
ShapeShape
Cell wallCell wall
ChloroplastsChloroplasts
VacuoleVacuole
NucleusNucleus
Food reservesFood reserves
regular irregular
peripheral centre
present absent
present small or absent
present absent
starch glycogen
4 The similarities and differencesbetween plant and animal cells
a cell membrane surrounding the cytoplasm
a nucleus
Both plant cells &
animal cells contain
4 The similarities and differencesbetween plant and animal cells
forcepsfleshy scale leaf of onion bulb
1. Peel off a small piece of epidermis from the inside of a scale leaf of an onion.
Experiment 1
Preparing temporary slides of the plant and animal tissues
A. Onion epidermal cells
4 The similarities and differencesbetween plant and animal cells
2. Cut it to a suitable size, about 5mm2.
Experiment 1
Preparing temporary slides of the plant and animal tissues
A. Onion epidermal cells
3.4 The similarities and differencesbetween plant and animal cells
3. Spread the tissue flat on a clean slide and add one drop of iodine solution on top of it.
iodine solution
epidermis
Experiment 1
Preparing temporary slides of the plant and animal tissues
A. Onion epidermal cells
4 The similarities and differencesbetween plant and animal cells
4. Gently cover it with a cover slip and make sure no air bubbles are trapped in it. Then examine the slide under the low power of a microscope.
cover slip
Experiment 1
Preparing temporary slides of the plant and animal tissues
A. Onion epidermal cells
The similarities and differencesbetween plant and animal cells
1. Obtain epithelial cells by gently scraping the inside of your cheek (in your mouth) with a clean toothpic
Experiment 2
Preparing temporary slides of the plant and animal tissues
B. Epithelial cells The inside of the mouth
4 The similarities and differencesbetween plant and animal cells
methylene blue stain
2. Add a drop of methylene blue stain on the slide.
Experiment 2
Preparing temporary slides of the plant and animal tissues
4 The similarities and differencesbetween plant and animal cells
B. Epithelial cells The inside of the mouth
Experiment 2
Preparing temporary slides of the plant and animal tissues
cover slip
3. Gently cover it with a cover slip. Then examine the slide under the low power of a microscope.
4 The similarities and differencesbetween plant and animal cells
B. Epithelial cells The inside of the mouth
Magnification: 40X 100x 400X
Magnification: 40X 100x 400X
A. Onion epidermal cells
B. Epithelial cells The inside of the mouth
4 The similarities and differencesbetween plant and animal cells
Mind Map
consist of
working together to form
working together
to form
working together
to form
can be observed with
contain contain
contains
contains
contains
function function
function function
are used in are used inwhich are
Cells
microscope
control cells’ activities
respiration
non-living granules
food or waste materials
chloroplasts (in plant cells only)
photosynthesis
support the cells
control of materials in
and out of the cell
support and prevent entry
of excess water
mitochondria
Animal cells Plant cells
nucleus
chromosomes
cytoplasm vacuole
cell sap
cell membrane cell wall
tissues
organs
system