Lab practical 1 Flashcards
1
Q
Also called steroscopic microscopes
A
Dissecting microscopes
2
Q
includes both scanning and transmission
A
electron microscopes
3
Q
also called light microscopes
A
compound microscopes
4
Q
are used to view the surface of relatively larger specimens at lower power typically no more than 10x,
A
dissecting microscopes
5
Q
functions like elaborate magnifying glasses and would be used to observe the gross anatomy of a living, preserved, or dissected specimen at greater detail
A
dissecting microscopes
6
Q
scientific instruments that use a beam of highly energetic electrons to examine objects on a very fine scale (up to several 100,000x
A
electron microscopes
7
Q
What type of microscope do we use in lab
A
compound microscopes
8
Q
Describe how the compound microscope works
A
compound microscopes are limited by the physics to 500x or 1000x magnification, it consists of two lenses and associated hardware that make viewing of specimen easier
9
Q
the lower lens of the compound microscope is called
A
objective lens
10
Q
the uppermost lens of the compound microscope is called
A
the ocular lens
11
Q
the part through which the person looks through is
A
the uppermost lens which is the ocular lens
12
Q
are mounted on a turret, allowing rapid changing
A
the lower lens which are the objective lens
13
Q
name the power listed on the objective lenses scope
A
4x scanning power, 10x low power, 40x high power
14
Q
hols the ocular and objective lenses in place
A
the body tube
15
Q
most microbiological specimens are mounted on glass
A
slides
16
Q
glass slides with cover slips are placed on
A
the stage
17
Q
holds the slide firmly on the stage
A
usually clips or clamps
18
Q
what two objects are located beneath the stage
A
a light source and a condenser lens
19
Q
why is the compound microscope called light microscope
A
because it has a light source
20
Q
why must the specimen be sliced thin
A
the specimen must be sliced then enough so that light can pass through the specimen to be viewed
21
Q
focuses on light through a hole in the stage
A
condenser
22
Q
what does the condenser include
A
an iris
23
Q
varies the amount of light passing through a specimen
A
the iris
24
Q
what happens to the light as it passes through the specimen
A
the goes through the objective and ocular lens and through the eye of the observer
25
this image is calculated by multiplying the magnification of the ocular by the magnification of the objective
the total magnification
26
what happens to light as it passes through any object (glass, air, specimens, etc.),
it bends
27
the bending of light is called
refraction
28
is a measurement of the extent that the substance bends light
the refractive index of a substance
29
distortion of the image
excessive refraction
30
at magnifications of less than 500x
the distortion is minimal
31
we will not view specimens at any total magnification greater than
400x
32
when magnifications are high what becomes the problem
the distortion becomes so great the image details are lost
33
helps to remedy the distortion problem by eliminating the air gaps between the specimen and the objective lens
oil immersion lens
34
the 4th objective lens is
the oil immersion lens
35
topmost series of lenses through which an object is viewed
ocular lens or eyepiece
36
what is the magnifying power of the ocular lens on your microscope
10
37
holds the nosepiece at one end and eyepiece at the other end; conducts light rays
body tube
38
supports upper parts and provides carrying handle
arm
39
objectives
objective lens, scanning, low, and high power
40
hold 4x lens used to view the whole slide
scanning power objective lens
41
Holds 10x lens used to view objects in greater detail
low-power objective
42
holds 40x lens used to view the objective in even greater detail
high- power objective
43
holds 100x lens and is used in conduction with oil to view objects with the greatest magnification
oil immersion objective lens
44
what lens are you never suppose to use
the oil immersion objective lens if your compound/light microscope has one
45
knob used to bring object into approximate focus; used only with low-power objective
coarse-adjustment knob
46
knob used to bring object into final focus
fine-adjustment knob
47
controls amount of illumination used to view the object
diaphragm or diaphragm control lever
48
an attached lamp that directs a beam of light up through the object
light source
49
the flat surface of the microscope that rests on the table
base
50
holds and supports microscope slides
stage
51
aids in the accurate position of the slide
mechanical stage
52
what structures are present to move the stage
the mechanical stage control knobs
53
should you ever use something other than the mechanical stage control knobs
NO, you should never use anything to move the stage it will cause damage to the stage
54
two knobs that are usually located below the stage. one knob controls forward/reverse and the other controls right/left
mechanical stage control knob
55
what is the first rule for microscope use
the lowest power objective should be in position booth at the beginning and end of microscope use
56
what is the second rule for microscope use
use only lens paper for cleaning the lens
57
what is the third rule for microscope use
do not tilt the microscope when viewing a wet mount
58
what is the fourth rule for microscope use
keep the stage clean and dry to prevent rust and corrosion
59
what is the fifth rule for microscope use
do not remove parts of the microscope
60
what is the sixth rule for microscope use
keep the microscope dust-free by covering it after use
61
what is the 7th rule for microscope use
report any malfunctioning when you notice it. This will benefit you and those who use the microscope after you
62
what is the should you always do before the 1st rule for focusing the microscope
always start with lowest power objective lens on you microscope or the scanning lens with the compound microscope
63
what is the first thing you do after making sure you at the lowest power objective lens when focusing the microscope
turn the nosepiece so that the lowest power lens is in straight alinement over the stage
64
what is the second rule of focusing the microscope
alway begin with focusing with lowest power objective
65
what is the 3rd rule of focusing the microscope
with the coarse-adjustment knob, lower the stage until it stops
66
what is the 4th rule of focusing the microscope
place slide on the stage and stabilize it with the clips
67
that is the 5th rule of focusing the microscope
again be sure the lowest power is in place
look grin the side
decrease the distance between the stage and the objective lens until the lens comes to an automatic stop or is no closer than 3mm above the slide
68
Why would it be a bad idea for the slide and objective lens to come into contact
you could break the slide or damage the lens
69
what is the 6th rule of focusing the microscope
while looking in to the eyepiece, rotate the diaphragm lever to give the maximum amount of light
70
what is the 7th rule of focusing the microscope
slowly increase the distance between the stage and the objective lens, using the coarse adjustment knob until the object comes into view or focus
71
what is the 8th rule of focusing the microscope
once the object is seen, you may need to adjust the amount of light. to increase or decrease the contrast rotate the diaphragm slightly
72
what is the 9th rule of focusing the microscope
use the fine-adjustment know to sharpen the focus if necessary
73
what is the 10th rule of focusing the microscope
practice having both eyes open when looking through the eyepiece, as it greatly reduces eyestrain
74
define inversion
the act of inverting something or a reversal of the normal
75
define parfocal
once the object is in focus with lowest power in our case scanning power, it should be nearly in focus with the higher power
76
How do you go from scanning power to high power
1. bring the object into focus
2. Make sure that the object is center in the field of the lowest objective
3. move to the higher objective (lower power 10x) by turning th nosepiece until you hear or feel it click into place
4. Do not change the focus
5. if any adjustment is needed use only the fine-adjustment knob
6. remember always use fine-adjustment for higher powers
7. repeat steps 2 and 4`
8. when you finish your observation rotate the nosepiece until the lowest power objective clicks into place
77
How is total magnification calculated
by multiplying the magnification of the ocular lens (eyepiece) by the magnification of the objective lens
78
power of objective x power of ocular =
total magnification
79
what is the power of ocular
10
80
4x10 =
scanning 4 x 10 power of ocular = 40
81
10 x 10 =
low 10 x 10 power of ocular = 100
82
40 x 10 =
high 10 x 10 power of ocular = 400
83
How do properly put up your microscope?
1. Remove any slides on the stage.
2. Make sure the scanning objective is locked in place.
3. Returned all slides to the correct slot in the slide tray.
4. If you made any wet mounts, make sure to clean the slide and cover slip and return them to the tray
5. If you break any slides or cover slips, throw them away into the trash labeled GLASS ONLY
6. Center the mechanical stage
7. Lower the mechanical stage or raise the nosepiece
8. Turn off the scope (light source)
9. Wrap and tie the cord using the plastic ties provided with the cord. DON'T WRAP CORD AROUND ANY PART OF THE MICROSCOPE
10. Place dust cover over microscope
11. Carry microscope with two hands and by the base. Store with the number that corresponds to the number on the desk
12. Make sure cord is on the shelf not hanging
13. Make sure arm is facing out. when do properly the # on the microscope base that correspondss with your station number can be seeen
84
what is biochemistry
the study of the chemistry of life
85
all living organisms consists of
organic compounds called carbon
86
molecules are made of smaller subunits called
monomers
87
what are known as the building blocks
monomers
88
monomers or building blocks line together to form
larger molecules called polymers
89
name the four class biological molecules are divided into macromolecules
1. lipids which includes fats, waxes, and oils
2. carbohydrates which are compromised of sugars that form starch and cellulose
3. Proteins which are composed of amino acids
4. Nucleic acids which include DNA and RNA
90
includes fasts, oils, steroids, waxes
lipids
91
lipids are the main components of the
plasma membrane of all living cells
92
the lipids found in plants are
oils
93
the lipids found in animals are
fats
94
are solids at room tempreature
oils are liquids
95
Lipids are _______, ________
non-polar, hydrophobic, they do not dissolve in water
96
when doing the lipid experiment using the full pipette of water and the full pipette full of vegetable oil to the same tube. What property of lipids explain the results you obtained
non-polar, hydrophobic, because lipids do not dissolve in water
97
is there anyway you can dissolve the oil in water
through use of detergent, soap and or dishwashing liquid
98
what is Sudan IV used to identify
the presence of a fat or oil
99
Using sudan IV what color was the lipid layer
hot pink
100
what color was the water layer
cloudy white
101
Sudan IV indicates the presence of what macromolecule
lipids
102
What property does Sudan IV have in order to react with this macromolecule?
neutral and hydrophobic
103
can be simple sugars or polymers made up of many sugar units
carbohydrates
104
carbohydrates are organic molecules
made of carbon, hydrogen and oxygen
105
simplest sugars are
monosaccharides
106
maonosaccharides are comprised of
one sugar unit
107
most common monosaccharide is
glucose
108
what is the function of glucose
serves as the immediate source of energy
109
the primary form of sugar stored in the human body
glucose
110
the main sugar found in most fruits
frutose
111
What is the molecular molecule for glucose and fructose
C6H12O6
112
how are glucose and fructose different
Fructose and glucose have the same molecular formula but differ structurally
113
```
CH2OH
I
H / C ------------O
I / I \ H
C H \ I
I \OH H / C
OH I I I
C _____ C OH
I I
H OH
```
GLUCOSE
C6H12O6
114
CH2OH O CH2OH
I
I
Frutose
| C6H12O6
115
What is the difference between glucose and fructose?
different structures or structural formulas
116
how many carbon atoms do glucose and fructose have
6
117
What is the molecular formula for glucose
C6H12O6
118
What is the molecular formula for fructose?
C6H12O6
119
Can be bonded together to form
monosaccharides
120
what contains two sugar units linked by a glycosidic bond
disaccharides
121
table sugar
sucrose
122
in seeds
maltose
123
milk sugar
lactose
124
is a disaccharide that consists that consists of glucose unit bonded to a fructose unit
common table sugar
125
sucrose is made of what two monosaccharides?
glucose and fructose
126
what is the molecular formula of sucrose
C12 H22 O11
127
what molecule must be lost in order to produce sucrose
one molecule of H2O must be lost
128
The joining of two monosaccharides to produce a disaccharide occurs through a
dehydration reactions
129
a indicator for monosaccharides
Benedict's solution
130
what is the positive indicator for monosaccharaides
orange
131
would you expect to see the same results in the Benedicts solution for sucrose as the sample
no because there is a difference in structure and structural formula
132
when using Benedict's soution for sucrose what color do you observe
blue
133
what does the results tell you about Benedict's solution as an indicator?
it allows the you to detect the difference between a monosaccaride and disaccharide
134
If more than two sugar units are joined by a glycosidic bond, the carbohydrate is called a
polysaccharide
135
what are some examples of polysaccharides
glycogen, starch, and cellulose
136
the polysaccharide found in animals
glycogen
137
the polysaccharide found only in plants and cellulose
starch
138
is a polysaccharide only in the cell walls of plants
starch
139
the principal polysaccharide used by plants to store glucose for later use as energy
starch
140
often stores starch in seeds or other specialized organs
plants
141
common sources of starch include rice, beans, wheat, corn potatoes etc.
plants often store starch in seeds or other specialized organs
142
What happens when humans eat starch
an enzyme that occurs in saliva and in the intestines called amylase breaks the bonds via hydrolysis reactions between the repeating glucose units this allowing sugar to be stored into the blood stream.
143
an enzyme that occurs in saliva and in the intestines called amylase breaks the bonds via hydrolysis reactions between the repeating glucose units this allowing sugar to be stored into the blood stream.
what happens when humans eat starch
144
the enzyme that occurs in saliva and in the intestines is called
amylase
145
the function of the enzyme amylase
breaks the bonds via hydrolysis reactions between the repeating glucose units, this allows sugar to be stored into the blood stream
146
what allows sugar to be stored into the bloodstream
the enzyme amylase breaks the bonds via hydrolysis reactions between the repeating glucose units
147
What happens once absorbed into the bloodstream
the human body distributes glucose to the areas where it is needed for energy or stores it as its own special polymer - glycogen
148
name another polymer of glucose
glycogen
149
The polysaccharide used by animals to store energy
Glycogen
150
Bonded to together to form glycogen molecules
Excess glucose
151
The animals stores in the liver and muscles tissues as an "instant" source of energy
Excess glucose is bonded together to form glycogen molecules
152
Both starch and glycogen are
Polymers of glucose
153
What structural differences do you observe between starch and sucrose
Starch has long chains
154
what monomer units do you observe in starch?
glucose
155
the most common test for a polysaccharide is
Lugol's test
156
In the Lugol's test what color is for the presence of starch
blue-black
157
dropping a very small drop of Lugol's on paper is what color and why
brown because lugol's is an indicator of polusaccaharide which paper is made out of
158
macromolecules with a diverse range of functions
proteins
159
proteins exist as
enzymes, antibodies, hormones, and transport proteins
160
Proteins are made up of
amino acids linked by peptide bonds
161
how many amino acids occur in nature
20
162
Proteins are also known as
polypeptides
163
H O
+ I II
H3N--C--C-O H3N----C----CO O ------> H3N
TRY TO REMEMBER THE 1ST IS AN AMINO ACID 1 THE SECOND IS AMINO ACID 2 AND THE THIRD IS A DIPEPTIDE
164
The biuret test is a positive indicator of the number of
peptide bonds in proteins
165
In the biuret test what is the color in the presence of proteins
pink to purple
166
why are proteins known as polypeptides
amino acids are linked by peptide bonds and there are many
167
what color does the bieuret solution turn in the presence of a great number of peptide bonds?
violet
168
comprised of DNA and RNA
nucleic acids
169
the genetic material of life
DNA and RNA
170
adds red coloration to lipids
Sudan IV
171
an indicator of the presence of monosaccharides
BENEDICT'S SOLUTION
172
an indicator of the presence of polysaccharides
lugol's test
173
an indicator for the presence of polypeptides
biuret test
174
common feature found in all cells
the plasma membrance
