Text C Biology 7.2 Cells And Technology Flashcards
(119 cards)
1
Q
Why are the images created by microscopes called ‘micrographs’?
A
The term ‘micrograph’ is derived from the roots ‘micro-‘ meaning small and ‘-graph’ meaning writing or drawing.
2
Q
What is the combined power of modern compound light microscopes?
A
The combined power can magnify as much as 2000x.
3
Q
Who designed the first compound microscope?
A
Zacharias Janssen.
4
Q
What distinguishes a compound microscope from a simple microscope?
A
A compound microscope uses two or more lenses placed one on top of the other.
5
Q
What are compound microscopes that view objects illuminated by visible light called?
A
Compound light microscopes.
6
Q
What was a limitation of Robert Hooke’s compound light microscope?
A
The quality of the lenses was poor, allowing him to see little detail.
7
Q
In what century did methods for producing better-quality lenses emerge?
A
In the 1800s.
8
Q
What type of microscope can view objects too small for light microscopes?
A
Electron microscope.
9
Q
What illuminates specimens in an electron microscope?
A
A beam of electrons.
10
Q
What is a photograph of an image from an electron microscope called?
A
Electron micrograph.
11
Q
How much can electron microscopes magnify images?
A
Up to 1.2 million times.
12
Q
What components are used to focus electrons in a transmission electron microscope?
A
Magnets.
13
Q
Fill in the blank: The earliest microscopes were called ______ microscopes.
A
simple
14
Q
True or False: The first compound microscope used only one lens.
A
False.
15
Q
What type of lenses do compound light microscopes use?
A
Ocular lens and objective lens.
16
Q
What improvements allowed scientists to explore cells in greater detail?
A
Advances in computer and optical technology.
17
Q
What is the role of the condenser lens in a microscope?
A
To focus light onto the specimen.
18
Q
What type of microscopy is commonly used to study prepared slides of stained cells?
A
Compound light microscopy.
19
Q
What is the transmission electron microscope (TEM)?
A
One of two main types of electron microscopes
The first TEM was built by German scientists in 1931 and improved by Canadian scientists in 1938.
20
Q
How does the TEM produce an image?
A
A beam of electrons is transmitted through a specimen
This produces a two-dimensional image magnified 10,000X to 100,000%.
21
Q
What is the maximum magnification of the TEM?
A
Over 1 million times
This allows for viewing internal structures and details of specimens.
22
Q
What is the scanning electron microscope (SEM)?
A
A type of electron microscope that creates three-dimensional images
Designed by German scientists in the 1930s.
23
Q
How does the SEM create images?
A
It sweeps a beam of electrons over an object
This allows for viewing the shapes of specimens in realistic detail.
24
Q
What is the maximum magnification of the SEM?
A
300,000X
Most specimens are easier to view at magnifications less than 10,000X.
25
What is required for viewing objects with the TEM?
Specimens must be thinly sliced and placed under a vacuum
## Footnote
This removes moisture and other interfering particles.
26
What type of image does the SEM produce?
A three-dimensional image
## Footnote
Only the surface of an object can be observed.
27
What is the function of the confocal laser scanning microscope?
Produces three-dimensional images of cells and their components
## Footnote
Described on page 268.
28
What does the scanning tunneling microscope produce an image of?
The atomic structure of the cell surface
## Footnote
Also described on page 268.
29
What is the function of a scanning tunnelling microscope (STM)?
Allows scientists to obtain images of atoms on an object's surface
## Footnote
The STM revolutionized microscopy in the mid-1980s and has more magnifying power than an electron microscope.
30
What type of images can an STM produce?
Images of molecules such as DNA
## Footnote
The STM's high magnifying power enables detailed imaging at the molecular level.
31
How does a scanning tunnelling microscope (STM) create images?
A fine metal probe is brought near the specimen, and electrons flow between the probe and the specimen's surface
## Footnote
The probe follows surface contours, and this information is processed by a computer.
32
What is the significance of the confocal laser scanning microscope (CLSM)?
It allows the study of thick specimens without cutting them
## Footnote
Invented in the 1960s, it was introduced elsewhere in the 1980s.
33
Describe the process used by a CLSM to study specimens.
A laser beam is directed at different planes of the specimen to create two-dimensional images
## Footnote
This results in optical 'slices' that can be stitched together into a three-dimensional image.
34
What is the analogy used to explain how CLSM works?
Studying a whole loaf of bread by examining several slices
## Footnote
This illustrates how CLSM analyzes layers of a specimen without needing to cut it.
35
What advantages do modern microscopes have when integrated with computers?
They can save images, display them on monitors, and allow for image manipulation
## Footnote
Computers improve precision and image quality and make operation easier.
36
What can researchers do with images obtained from modern microscopes?
Retrieve, manipulate, and study the images long after they were created
## Footnote
This capability enhances research and analysis processes.
37
Fill in the blank: The confocal laser scanning microscope was invented by _______.
[Czech researchers]
38
True or False: The CLSM requires specimens to be cut for examination.
False
## Footnote
The CLSM can study thick specimens without cutting them.
39
What type of images does the CLSM produce from a specimen?
Two-dimensional images that are combined into a three-dimensional view
## Footnote
This process allows for detailed analysis of complex specimens.
40
What high school did Néha Datta attend?
Western Canada High School in Calgary, Alberta
41
At what age did Néha Datta enter the Intel International Science Fair?
17
42
What was the focus of Néha Datta's project at the Intel International Science Fair?
Tracking mammalian neural stem cell expansion
43
What conditions are scientists hoping to repair using neural stem cells?
Parkinson's disease, multiple sclerosis, and other conditions
44
What is required for research and treatment involving neural stem cells?
A large supply of neural stem cells (NSC)
45
What organism is often used for studying cell development due to its simplicity?
Caenorhabditis elegans
46
How many body cells does C. elegans have?
About 1000
47
What do genes direct?
The activities of our cells
48
What are genes made of?
Long molecules called DNA
49
Where is DNA found in a cell?
In the nucleus
50
What disease is caused by a change in a gene, leading to deformed red blood cells?
Sickle cell anemia
51
What is gene sequencing?
Mapping the order of all of a gene's bases
52
What are the four kinds of bases in DNA?
* Adenine (A) * Cytosine (C) * Guanine (G) * Thymine (T)
53
What is the Human Genome Project (HGP)?
An international project to sequence all 30,000 to 40,000 human genes
54
What can scientists learn more quickly now that they have sequenced genes?
The functions of the genes
55
What is the purpose of comparing gene sequences from different sources?
To look for differences or similarities between the gene sequences
56
True or False: Not all differences in gene sequences indicate that one gene is 'faulty'.
True
57
What techniques do scientists use to determine the order of bases in genes?
Automated gene sequencers
58
Fill in the blank: The order of bases in DNA can be traced by following the order of _______.
the four different coloured bands
59
What high school did Néha Datta attend?
Western Canada High School in Calgary, Alberta
60
At what age did Néha Datta enter the Intel International Science Fair?
17
61
What was the focus of Néha Datta's project at the Intel International Science Fair?
Tracking mammalian neural stem cell expansion
62
What conditions are scientists hoping to repair using neural stem cells?
Parkinson's disease, multiple sclerosis, and other conditions
63
What is required for research and treatment involving neural stem cells?
A large supply of neural stem cells (NSC)
64
What organism is often used for studying cell development due to its simplicity?
Caenorhabditis elegans
65
How many body cells does C. elegans have?
About 1000
66
What do genes direct?
The activities of our cells
67
What are genes made of?
Long molecules called DNA
68
Where is DNA found in a cell?
In the nucleus
69
What disease is caused by a change in a gene, leading to deformed red blood cells?
Sickle cell anemia
70
What is gene sequencing?
Mapping the order of all of a gene's bases
71
What are the four kinds of bases in DNA?
* Adenine (A) * Cytosine (C) * Guanine (G) * Thymine (T)
72
What is the Human Genome Project (HGP)?
An international project to sequence all 30,000 to 40,000 human genes
73
What can scientists learn more quickly now that they have sequenced genes?
The functions of the genes
74
What is the purpose of comparing gene sequences from different sources?
To look for differences or similarities between the gene sequences
75
True or False: Not all differences in gene sequences indicate that one gene is 'faulty'.
True
76
What techniques do scientists use to determine the order of bases in genes?
Automated gene sequencers
77
Fill in the blank: The order of bases in DNA can be traced by following the order of _______.
the four different coloured bands
78
What is the second leading cause of death in North America?
Cancer
## Footnote
Heart disease is the number one killer.
79
What primarily causes most cancers?
Damage to genes
80
What are mutations?
Changes in the sequence of bases
81
How do mutations affect cancer risk?
They increase a person's chance of developing cancer
82
What happens when mutations occur in cells?
Cells grow and divide uncontrollably, forming a tumour
83
How do normal cells differ from cancer cells in growth?
Normal cells are prevented from growing too close together; cancer cells grow without restrictions
84
What do researchers analyze to learn about cancer-causing genes?
Gene sequences
85
What is the purpose of determining a gene's sequence?
To learn how the gene affects cell activity
86
What is a virus?
A non-cellular structure made up of genetic material enclosed in a protein coat
87
How does a virus reproduce?
By taking over the host cell's reproductive machinery
88
What is a prion?
A protein that converts from its normal form into a harmful particle
89
What diseases are caused by prions?
Several deadly diseases, including Bovine Spongiform Encephalopathy (BSE)
90
Do prions have independent life functions?
No, they are not considered a functional unit of life
91
Fill in the blank: A _______ is a non-cellular structure that can reproduce in living tissue.
virus
92
Fill in the blank: Bovine Spongiform Encephalopathy is also known as _______.
mad cow disease
93
True or False: Viruses can infect plants and bacteria.
True
94
What type of research is currently underway in Canada regarding cancer?
Research on the genetic basis of various cancers
95
What is recommended for a class presentation regarding cancer?
Present findings about one type of cancer thought to have a genetic basis
96
What are the key characteristics that all living organisms share?
* Require energy
* Produce waste
* Reproduce
97
What are HeLa cells named after?
Henrietta Lacks
## Footnote
HeLa cells are derived from the cervical cancer cells of Henrietta Lacks, who donated them for research.
98
In what year were HeLa cells collected?
1951
## Footnote
Henrietta Lacks' cells were collected shortly after her diagnosis with cervical cancer.
99
What type of cancer did Henrietta Lacks have?
Cervical cancer
## Footnote
Ms. Lacks was diagnosed with cancer of the cervix, which ultimately led to her death.
100
What is the significance of HeLa cells in research?
They have enabled important successes in cancer research and provided basic knowledge about cell biology
## Footnote
HeLa cells continue to be a vital resource in scientific studies.
101
What is cell culture?
A technique where isolated cells are placed in nutrient-rich environments for growth
## Footnote
Cell culture allows researchers to study cells outside of their natural environment.
102
What are the generations of cells that result from growth and division in each culture called?
Cell lines
## Footnote
Cell lines are used for various research purposes, including cancer studies.
103
How do cancer cells differ from normal cells in culture?
Cancer cells can grow indefinitely, while normal cells have a limited lifespan outside the body
## Footnote
This distinction is crucial for research and treatment development.
104
What are stem cells often referred to as?
'Blank slate' cells
## Footnote
Stem cells have the unique ability to differentiate into various specialized cell types.
105
What can stem cells develop into?
All other types of specialized cells
## Footnote
This ability makes them a focal point in regenerative medicine.
106
Where are most adult stem cells located?
In the bone marrow
## Footnote
Adult stem cells in the bone marrow are responsible for producing new blood cells.
107
True or False: Adult stem cells can give rise to all cell types of the body.
False
## Footnote
Adult stem cells are limited in the types of cells they can produce compared to embryonic stem cells.
108
What potential applications do scientists hope to achieve with stem cells?
Develop treatments and cures for diseases, and grow tissues or organs for transplants
## Footnote
Stem cells hold promise for addressing various medical challenges.
109
Fill in the blank: The cells that grow from stem cells are specialized and lose the ability to produce _______.
other cell types
## Footnote
This limitation is a key characteristic of mature specialized cells.
110
What is the starting point of development for every multicellular organism?
A single cell.
## Footnote
This single cell undergoes a series of divisions to form all the cells of the mature organism.
111
What process allows a single cell to multiply into all the cells of a mature organism?
Cell divisions.
## Footnote
This process is crucial for the development of multicellular organisms.
112
What happens to cells as they divide?
They become specialized.
## Footnote
Specialization occurs as cells form different types of tissues, such as skin, blood, or leaf tissue.
113
What would likely happen if some of your cells stopped functioning properly?
You would get sick.
## Footnote
The specific health problem would depend on which cells malfunctioned and the reason for their failure.
114
Who was the first scientist to link malfunctioning cells to illnesses?
Rudolf Virchow.
## Footnote
Virchow believed studying the activity of infected or damaged cells was key to understanding disease.
115
What did Rudolf Virchow think was the best way to understand disease?
To study the activity of infected or damaged cells.
## Footnote
This approach was innovative during his time, as cell function was not fully understood.
116
What advancements have been made since Virchow's time regarding cell function?
Great advances in understanding how cells work and their contribution to disease.
## Footnote
Research has continued to evolve, enhancing our knowledge of cell biology.
117
What technologies have increased our knowledge of cells?
Light microscopes and electron microscopes.
## Footnote
These tools allow researchers to investigate cells in remarkable detail.
118
How have microscope technologies impacted our understanding of cells?
They have resulted in a better understanding of the structure and function of cells.
## Footnote
Enhanced imaging techniques have led to significant discoveries in cell biology.
119
What areas of research are linked to advances in our understanding of cells?
Gene mapping, cancer research, and stem cell research.
## Footnote
These fields have benefited from improved knowledge and technologies related to cells.
