B1- Cell Biology Flashcards
1
Q
What are the two types of microscopes?
A
Light and electron microscopes
2
Q
What type of microscope was invented first?
A
The light microscope.
3
Q
What is the maximum magnification of a light microscope?
A
2000x
4
Q
What is the maximum magnification of an electron microscope?
A
2 million times
5
Q
What is resolving power? (2 points)
A
The ability to tell 2 things apart.
The fineness of detail in an image.
6
Q
What are the advantages of a light microscope? (5)
A
Cheaper portable see colour easy to use can observe live specimens
7
Q
What are the disadvantages of a light microscope? (3)
A
Only 2D images
low resolution
low magnification
8
Q
What are the advantages of an electron microscope? (3)
A
3D images
high magnification
high resolution
9
Q
What are the disadvantages to an electron microscope? (5)
A
Very expensive only black and white images specimen must be dead take up a whole room need high levels of training to operate
10
Q
What is an order of magnitude?
A
A number to the base of 10, used to make comparisons.
11
Q
What is the formula for magnification?
A
Magnification= Image size / actual size
12
Q
What is the formula for magnification in terms of the actual size of an image?
A
Actual size= Image size/magnification
13
Q
What is the formula for magnification in terms of image size?
A
Image size= magnification x actual size
14
Q
The ability to tell two objects (that are close together) apart is called the?
A
Resolving power/resolution
15
Q
The type of microscopes found in secondary schools is a:
A
Light microscope
16
Q
The type of microscope only found at universities or research labs is the:
A
Electron microscope
17
Q
What are the 5 parts of an animal cell?
A
Cell membrane Nucleus Cytoplasm Mitochondria Ribosome
18
Q
What does a cell membrane do?
A
Controls what enters and exits the cell
19
Q
What part of the cell controls what enters and exits the cell?
A
Cell membrane
20
Q
What is the function of the nucleus of the cell? (2 points)
A
Controls the activities of the cell
Holds the DNA
NOT the brain
21
Q
What part of the cell controls the activities of the cell?
A
The nucleus
22
Q
Where is the DNA stored in the cell?
A
In the nucleus
23
Q
What is cytoplasm? (2 points)
A
Jelly-like substance that fills the cell.
Where the reactions of the cell take place.
24
Q
What is the jelly like substance that fills the cell called?
A
The cytoplasm
25
Where do reactions inside the cell take place?
In the cytoplasm.
26
What is the purpose of the mitochondria?
Where respiration takes place, so the cell has energy for what it needs to do.
27
Where does respiration take place in the cell?
In the mitochondria.
28
What is the function of the ribosomes?
Where protein synthesis occurs (where proteins are made)
29
Where does protein synthesis take place?
Ribosomes
30
Where are proteins made?
Ribosomes
31
What may be in a plant cell but never in an animal cell? (3 points)
Cell wall
Permanent vacuole
Chloroplasts
32
What is the purpose of the cell wall?
Strengthens the cell and helps it to keep its shape.
33
What strengthens the cell and helps it keep its shape?
The cell wall
34
What is a plant cell wall made from?
Cellulose
35
What part of the cell is made from cellulose?
Cell wall
36
In what type of cell would you find a cell wall?
Plant cells and prokaryotic cells (bacterial cells)
37
What is the purpose of the permanent vacuole?
To store things for the cell and to keep the cell rigid.
38
What part of the cell keeps it rigid?
The permanent vacuole
39
What part of the plant cell is filled with cell sap?
The permanent vacuole.
40
What is the function of the chloroplasts?
Where photosynthesis takes place.
41
Where in a cell does photosynthesis take place?
In the chloroplasts.
42
What part of the cell contains chlorophyll?
Chloroplasts
43
What is the scientific term for both plant and animal cells.
Eukaryotic cells
44
What is the scientific term for bacterial cells?
Prokaryotic cells
45
What type of organism is a prokaryote?
A bacteria
46
What type of organism is a eukaryote?
A plant or animal
47
What to both prokaryotic and eukaryotic cells have?
Cell membrane, ribosomes, DNA, and cytoplasm
48
What makes prokaryotic cells different from eukaryotic cells?
Prokaryotic cells don’t have a nucleus. They also have a cell wall not made from cellulose.
49
What is a small loop of DNA called?
A plasmid
50
What type of cell might have a plasmid?
A prokaryotic cell
51
A millimetre is how many orders of magnitude smaller than a meter?
3
52
A micrometer is how many orders of magnitude smaller than a meter?
6
53
A nanometer is how many orders of magnitude smaller than a meter?
9
54
What is the symbol for nanometer?
nm
55
What is the symbol for micrometer?
The weird u
56
What is differentiation in relation to cells?
When a cell changes to become a specific type of cell to do a specific job.
57
What are cilia?
Hair like structures on the surface of some cells.
58
What are the hair like structures on some cells called?
Cilia
59
What do cilia do?
They push substances past the surface of the cell, for example sweep mucus away from the lungs
60
What are undifferentiated cells called?
Stem cells
61
What is it called when a cell changes to become a specific type of cell to do a specific job.
Cell differentiation
62
What is the job of a sperm cell?
To carry the male’s DNA to the female’s egg cell to allow for reproduction.
63
What type of cell carries the male DNA to the female egg cell?
Sperm cell
64
Why does a sperm cell have a tail?
In order to swim to reach the egg
65
What specialization allows a sperm to reach the egg? (2 points)
```
A tail (flagellum) to help it swim
Lots of mitochondria to give it enough energy
```
66
Why does a sperm cell have lots of mitochondria?
To give it enough energy to swim all the way to the egg.
67
What specialization does a sperm cell have to get into the egg (after it gets there)
Enzymes in its acrosome (head) to digest the outer layers of the egg.
68
What type of specialized cells carry electrical impulses from one area of the body to another?
Nerve cells
69
What is the job of a nerve cell?
To carry electrical impulses (signals) from one area of the body to the other.
70
What are some specializations that nerve cells have to help them do their job? (2 points)
A long axon to reach long distances.
| Tiny finger-like dendrites to connect to other nerve cells.
71
When does most of the differentiation happen in human cells?
In the womb as an embryo.
72
Where are root hair cells found?
On the surface of plant roots
73
What type of specialized cells are found on the surface of plant roots?
Root hair cells
74
What are some specializations of a root hair cell (3)
- large vacuole to increase absorption of water
- many mitochondria for energy for active transport
- long thin shape to increase surface area to volume ratio
75
Why does a root hair cell have a large surface area?
To allow for more transport to take place across the membrane
76
Why does a root hair cell have a large vacuole?
To increase the rate of osmosis
77
Why does the root hair cell have many mitochondria?
To provide energy for active transport of mineral ions into the cell
78
When are plant cells able to differentiate?
Throughout their lives
79
The cells of which type of organism are able to differentiate throughout their lives?
Plant cells
80
What type of plant tissue is undifferentiated?
Meristem tissue
81
What do xylem cells transport?
Water through the plant
82
What are the walls of xylem cells made from?
Lignin
83
What cells carry water through a plant?
Xylem cells
84
What type of differentiated plant cells are not alive when carrying out their function?
Xylem cells
85
Tubes of which type of cells have no ends so that substances call flow easily?
Xylem cells
86
What type of specialized cell carries dissolved sugars through a plant?
Phloem cells
87
What specializations do phloem cells have to help them carry out their function? (2)
- sieve plates between neighbouring cells to allow movement of solutions from cell to cell
- Companion cells with lots of mitochondria to provide energy for the active transport of sugars.
88
What do phloem cells carry?
Dissolved sugars through a plant
89
True or false: Phloem cells are dead when they carry out their function?
False, they are alive. Xylem cells are dead.
90
When looking at a cell through a microscope, what is usually the largest organelle you can see?
The nucleus
91
How can you tell the difference between a plant and an animal cell under a microscope?
- Plant cells are more square/fixed in their shape because of their cell walls
- If they have green chloroplasts they will be plant cells
92
What is the part of a microscope called that you look through?
The eyepiece
93
What position should the stage be in when you first put a slide on a microscope?
The lowest position
94
What is the name of the part of the microscope where you put the slide?
The stage
95
What objective lens should you use first to see the specimen?
The lowest power objective lens (the lowest number)
96
What should you do if the image in a microscope isn’t clear?
- Turn the focusing wheel to try to focus the image
| - Clean the lens with a special wipe
97
What do you need to remember when making a scientific drawing? (4)
- Use pencil
- Use shading only to distinguish different structures
- Use straight lines to label your drawing
- Write the magnification if using a microscope.
98
What are the three main stages of the cell cycle?
1) Interphase
2) Mitosis
3) Cell division
99
What happens during interphase? (3)
- The cell grows
- organelles like ribosomes and mitochondria double
- DNA is replicated
100
What happens during mitosis? (2)
- One set of chromosomes are pulled to each end of the cell
| - The nucleus divides
101
What happens during the cell division stage of the cell cycle? (2)
- The cell membrane, organelles, and cytoplasm divide
| - Two identical cells form
102
In which stage of the cell cycle does a cell spend most of it’s life?
Interphase
103
During which stage of the cell cycle does a cell grow?
Interphase
104
During which stage of the cell cycle does a cell replicate it’s DNA?
Interphase
105
During which stage of the cell cycle are chromosomes pulled to each end of the cell?
Mitosis
106
During which stage of the cell cycle do the cell membranes, organelles and cytoplasm divide?
Cell division
107
During which stage of the cell cycle does the cell increase the number of ribosomes and mitochondria?
Interphase
108
During which stage of the cell cycle does the nucleus divide?
Mitosis
109
During which stage of the cell cycle do two identical cells form?
Cell division
110
What type of cells come out of mitosis?
Two identical daughter cells
111
What is a cell that is about to divide called?
A parent cell
112
What makes a cell diploid?
Having 2 (double) sets of chromosomes
113
What is the process that produces two identical daughter cells?
Mitosis
114
What are three uses of mitosis?
- growth
- repair of damaged tissue
- asexual reproduction
115
What type of cell division is used for growth and repair of tissues?
Mitosis
116
What type of cell division is used in asexual reproduction?
Mitosis
117
What is a stem cell?
An undifferentiated cell in an organism
118
Where are stem cells found in adults?
Bone marrow
119
What are the two types of animal stem cells?
- embryonic stem cells
| - adult stem cells
120
What is special about stem cells?
They are able to become any type of cell through differentiation.
121
Where are stem cells found in plants?
In the meristem tissue
122
What are clones?
Organisms that are genetically identical
