Download Disease Unit

“I Can...” Statements
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“I can” statements help you to know exactly what you need to be getting out of today’s lesson. When you
come into class, immediately check the board for today’s statement and copy it into your notebook. At
the end of the lesson, if you feel you can do the statement, then check the box. If you don’t check it, don’t
worry! Re-watch the video at home that teaches that subject and focus on it during homework and
review time. Ask your teacher for more help on that subject after school. When you know it, check the
box and be proud of your hard work!
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Daily Warm-ups
When you come into class every day, there will be a warm-up ready for you to do. Write today’s date
and the warm-up in the next unused warm-up box.
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Diseases Vocabulary
Read and study the definitions of each word. In the box, you have three options you can do for each word.
Each week, complete the boxes for the vocabulary words that are being used in class that week. For each word,
you may draw a picture that represents the word, write a sentence that uses the word, or make a connection with
the word to real life or another vocabulary word. For example, “We learned about photosynthesis, which is a
kind of chemical reaction with sugar as a product.”
Vocabulary Word
Definition
Antibiotic
A chemical that kills
bacteria or slows their
growth without harming
body cells.
Asexual
reproduction
A reproductive process
that involves only one
parent and produces
offspring that are
identical to the parent.
Bacillus
Round bacteria shape.
Bacteria
Single-celled organisms
that lack a nucleus.
Bacteriophage
A virus that infects
bacteria.
Binary Fission
The process of cell
division that bacteria use
to reproduce.
Biotechnology
The use of living
organisms to solve a
problem.
Draw a Picture, Write a Sentence or Make a Connection
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Capsid
The protective protein
coat surrounding the
DNA or RNA of a virus.
Cell Wall
A rigid layer around the
outside of a bacteria cell
that gives support and
protection.
Cell Membrane
A layer around the
outside of a bacteria cell
that controls what enters
or exits the cell.
Cilia
Short, hairlike structures
on the outside of cells that
assists with movement.
Clone
An organism or cell that
is produced asexually
from a parent organism or
cell. It is genetically
identical to the parent.
Cocci
Round bacteria shape.
Cytoplasm
The region between the
cell membrane and the
nucleus.
DNA
The material in all living
organisms that carries
genetic information.
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Epidemic
A localized disease
outbreak.
Ethics
Moral principles that
govern a person’s or
group’s behavior.
Eukaryote
A cell with a nucleus.
Flagellum
A long, whiplike structure
that helps a cell to move.
Fungus
An organism that has cell
walls, a nucleus, uses
spores to reproduce, and
is a heterotroph that feeds
by absorbing its food.
Genetically
Modified
Organism
An organism whose DNA
has been altered by
humans using genetic
engineering.
Genetics
The study of inherited
characteristics.
Hygiene
Practices that help
maintain health and
prevent disease.
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Hyphae
Infectious Disease
The branching, threadlike
tubes that make up the
bodies of multicellular
fungi
A disease caused by the
presence of a pathogen in
the body which can be
passed to another body.
Influenza
A highly contagious viral
infection of the
respiratory passages.
“The Flu”
Microbe
An organism that is too
small to be seen by the
naked eye.
Pandemic
A widespread disease
outbreak.
Pathogen
An organism that causes
disease.
Prokaryote
A cell without a nucleus.
Protists
A eukaryotic organism
that cannot be classified
as an animal, plant, or
fungus. Most are
unicellular, and some can
be parasites.
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Ribosome
A tiny structure located in
the cytoplasm of a cell
where proteins are
produced.
Sexual
Reproduction
reproductive process that
involves two parents that
combine their genetic
material to produce a new
organism, which differs
from both parents.
Spirillium
Spiral bacteria shape.
Stem Cell
An undifferentiated cell
from which all body cells
can be formed. Used
extensively for medical
research.
Vaccine
A substance that contains
weak or dead pathogens
that can still trigger the
immune system into
action.
Vector
An organism, often a
biting insect or tick, that
transmits a disease or
parasite.
Virus
A tiny, nonliving particle
that invades and then
reproduces inside a living
cell.
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Crossword Puzzle
Across
4. Reproduction where the offspring are genetically
identical to the one parent.
5. A virus that infects bacteria.
7. Just because science can do something, should it?
8. The protective protein coat around a virus.
11. A mosquito transmits malaria. The mosquito is a
_______.
12. To make sure milk is safe to drink, this is done to
it before it goes to the store.
13. Cell division
16. The organelle where proteins are made
17. One of the structures that bacteria can use to
move
18. The main body of a fungus that resembles roots
Down
1. A disease outbreak that affects many countries and
areas.
2. This is not a medicine that can cure a disease, but it
can help your body prevent getting the disease in the
first place.
3. Using a living thing to solve a problem.
9. Virus, bacteria, parasite or fungus
10. Antibiotics can not be used to treat this pathogen.
14. Once this was discovered, disease transmission
was greatly reduced.
15. Strep throat (streptococcus) has this shape.
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Bacteria
Bacteria are single-celled, prokaryotic organisms. The DNA in their cells is not contained in a nucleus.
Bacteria cells have one of three basic shapes: spherical, rodlike, or spiral.
Most bacterial cells are surrounded by a rigid cell wall that helps to protect the cell. Inside the cell wall
is the cell membrane that controls what materials pass into and out of the cell. Cytoplasm is the gel-like material
inside the cell membrane that fills all the extra space in the cell. Inside the cytoplasm are tiny structures called
ribosomes that are chemical factories where proteins are produced. The cell’s genetic material, or DNA, is also
located is also located in the cytoplasm and contains instruction for all the cell’s functions. Some bacteria have
flagella, which are long, whip-like structures that extend from the cell membrane and helps the cell to move.
Other bacteria use cilia to move, which are short hair-like structures covering the outside of the cell.
When bacteria have plenty of food, the right temperature, and other suitable conditions, they reproduce
frequently. Bacteria reproduce asexually using binary fission. Asexual reproduction is a process that involves
only one parent and produces offspring that are genetically identical to the parent.
Some bacteria cause disease and other harmful conditions. However, most bacteria are either harmless or
helpful to people. Bacteria are involved in oxygen and food production, environmental recycling and cleanup,
health maintenance, and medicine production. Bacteria are also important decomposers in many ecosystems.
Bacteria Shapes and Parts
Label the parts of the bacterial cell: cilia, DNA, flagella, cytoplasm, cell wall, cell membrane
Draw and label the three bacterial shapes (pg. 450).
______________
______________
______________
Asexual Reproduction
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Bacteria reproduce asexually using binary fission. This means that there is only one parent and the
offspring is genetically identical to the parent. All offspring are clones of the parent cell.
Color in the parts of binary fission to show how bacteria replicate.
Viruses
A virus is a tiny, nonliving particle that enters and then reproduces inside a living cell. Viruses are not
living because they do not grow, use energy, or respond to their environment. Although viruses can multiply,
they do so differently than other organisms. They can only multiply when they are inside another living cell,
which makes them similar to a parasite. The cell that is attacked by the virus is called the host.
Viruses vary in shape and size. They can be round, rod-shaped, brick shaped, bullet shaped, and many
other complex shapes. A bacteriophage is a special kind of virus that attacks bacteria cells. Viruses are much
smaller than bacteria cells.
All viruses have two basic parts: a protein coat that protects the virus and an inner core made out of genetic
material, which is either DNA or RNA. Every virus has unique proteins on its outer surface. The shape of these
proteins allows the virus to attach to a certain kind of host cell to infect it. The proteins are like a key that opens
only one kind of cell. Some viruses attack only mammals, or only Oak trees, etc.
Label the parts of a virus: Capsid, Genetic Material
Multiplying Bacteria
We know that bacteria can reproduce really fast. But, just how fast does it happen? Today you will calculate
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the growth of E.coli bacteria over the course of 4 hours and create a curve to represent the rate which these
bacteria reproduce.
Directions: Assume that you start with 2 E. coli bacteria. These bacteria reproduce by binary fission that means
each one splits in half to create two bacteria. E. coli split every 15 min. Calculate the number of E coli bacteria
present at each time interval in the table below.
Time
Elapsed
0
minutes
15
minutes
30
minutes
45
minutes
1
hour
1
hour
15
min
1
hour
30
min
1
hour
45
min
2
hours
Number
of E
coli
Time
Elapsed
2 hours 2 hour 2 hour 3 hours 3 hour 3 hour 3 hour
15 min 30
45
15
30 min 45 min
min
min
min
4 hour
Number
of E coli
Reproduction Rate of E. coli
140,000
120,000
100,000
80,000
60,000
40,000
20,000
0
0 :15
30 :45 1: 1:15 1:30 1:45 2 2:15 2:30 2:45 3 3:15 3:30 3:45 4
How Viruses Multiply
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Fill out the following chart. Use color and draw carefully to help understand the process of viral multiplication.
Description
Drawing
1.
2.
3.
4.
5.
Compare and Contrast Viruses and Bacteria
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How are they different?
Viruses
Category
Bacteria
How are they alike?
Bacteria that Dine on Vegetables
Bacteria are among the most numerous organisms on Earth. If a bacterium is in the right temperature range and
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has enough moisture and food, it can reproduce rapidly. In 24 to 48 hours, it can multiply so often that its offspring
form a visible colony. In this investigation you will witness the explosive growth as you grow bacteria on common
vegetables.
Materials
4 clear, resealable plastic bags
8 small pieces of masking tape
2 slices of baked sweet potato
2 cotton swabs
2 slices of baked potato
transparent tape
Procedure
1. Put a piece of masking tape on each bag. Write the following on the four different labels: “Potato-A” “PotatoB” “Sweet Potato-A” “Sweet Potato-B”
2. Predict where bacteria might be living in your classroom. Write down these predictions in the Observations
section. Choose one of the locations to test.
3. Get one slice of baked potato using the spatula. Take care that the spatula only touches one side of the potato,
and that nothing touches the other side.
4. Put this slice in the bag labeled “Potato-A”, with the untouched side facing up. Seal the bag securely and tape
the sealed edge shut.
5. Repeat step #3.
6. Put this slice in the bag labeled “Potato-B”, with the untouched side facing up.
7. Rub a cotton swab on the area in the classroom where you think bacteria might live. Then rub the cotton swab
on the untouched side of the potato in bag B. Seal the bag securely using tape.
8. Set both bags in the place where you teacher directs you to. Do not open the bags again. Dispose of the swab.
9. Repeat steps 3-8 with the Sweet Potato.
10. Observe the potato and sweet potato slices for 5 days. Do not open the bags. Each day, draw and record your
observations in the data table.
Observations
1. What locations in your classroom do you predict bacteria live?
2. Which location are you going to test?
Data Table
Day
Potato-A
Potato-B
Sweet Potato-A
Sweet Potato-B
1
2
3
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4
5
Questions
1. Large colonies of bacteria may look shiny or like mucus. Which bag(s) had the greatest growth of bacteria?
The least growth?
2. Do the organisms growing on the potato appear to be different from those growing on the sweet potato?
Why?
3. Why did you leave the slices untouched in the plastic bags labeled “A”?
4. Why did you not use your hand to put the potatoes in the bags? Why did you use a spatula?
5. What can you do at home to keep your vegetables fresh for longer?
6. Suppose you repeated this investigation, but this time you left the plastic bags labeled “A” open for a few
minutes before sealing them. What do you think you might observe? Why?
Fungi
The basic structural features of fungi are hyphae. Hyphae are microscopic branching threads filled with
cytoplasm and nuclei. Hyphae look like the roots of a plant, but do not confuse them! Hyphae are actually the
main body of the fungus. Sometimes the hyphae are divided into compartments by cross walls called septa. Fungi
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do not have chlorophyll and so cannot do photosynthesis. Fungi are heterotrophic, and feed on dead materials by
absorbing the nutrients. The hyphae produce an enzyme which digests the dead matter so that it can be absorbed.
Fungi reproduce sexually, which means that there
are two parent fungi which recombine their DNA
to form a unique offspring. The part of a
mushroom that you see coming out of the ground
is the reproductive structure. It contains the spores
which help to spread genetic information of the
mushroom.
There are many different kinds of fungi, but some
main categories include bread molds, mushrooms,
and yeast. Yeast is important to humans because
we use it to make bread and other products. Yeast
is the only single-celled fungus.
1. Why are fungi considered heterotrophic and
not autotrophic?
2. Are fungi producers, consumers, or
decomposers? Why is it classified like this?
3. Why would you not be killing a mushroom if you stepped on one in the forest?
4. Are fungi prokaryotic or eukaryotic? How did you figure that out from this reading?
5. Give two reasons why fungi are not plants.
A Really Big Fungus
Because many fungi live in the soil, we normally aren’t aware of them. However, their underground
networks of hyphae can become enormous.
In 1982, scientists discovered a specimen of the fungus Armillaria bulbosa living beneath about 150,000
square meters of soil in Michigan. Of course, scientists couldn’t see the entire fungus directly. Instead, they
compared the DNA of fungus samples taken at different locations. DNA is the substance that determines an
organism’s inherited characteristics. Each individual’s DNA is slightly different from other individuals of that
species. Scientists saw that DNA taken from neighboring locations were identical. Because of this, they knew
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that they were looking at samples of one very large fungus.
Scientists have taken samples of the fungus Armillaria bulbosa at the numbered locations on the map
below. Seven DNA types were identified from the samples. Assume that each DNA type identifies an individual
fungus.
DNA Type Type 1
Location
1,2,7
Type 2
Type 3
Type 4
Type 5
Type 6
Type 7
8,14,15,22
3,9,10,16,1
7,23,24,25
4,5,11,18
12,19,26,
27
6,13,20
21,28,29
1. Find the locations of each DNA type on the map. Draw lines on the map dividing the DNA types from one
another. Do not connect all the dots of the numbers listed. Draw a line encircling all the numbers listed.
2. Assume that each sample location corresponds to an area of 1,600m2. How many square meters do the largest
and smallest individual fungi on the map cover?
3. Assume that there is 0.75 kg of biomass per square meter of fungus. What is the weight of the largest and
smallest fungi on the map?
4. If the hyphae in each square meter of fungus were lined up end to end, they would stretch about 90 meters.
What is the length in kilometers of the hyphae of the largest fungus on the map?
Parasites
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Parasites are organisms that live on or in humans and gain nutrition from the host. Some parasites such
as hookworms and tape worms live in the intestines and absorb nutrition from food that the host injests. Other
parasites live on the host and feed off blood by biting the host such as lice. Other parasites do not live on the host
but only use the host for nutrition, such as mosquitos.
Protists are a type of single-celled, eukaryotic organism that can sometimes be a parasite in humans.
Malaria, Giardia, and African Sleeping Sickness are all diseases caused by protist infections. Malaria infects
more than 300 million and kills more than 2 million people every year.
Common Human Infections
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Viruses
Bacteria
Fungus
Parasites
Infectious Diseases
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Use pages 492-496 in the Science book to complete this page.
Source
Examples of Method of
Transfer
Examples of Diseases Spread
in this Way
1. What are the four major groups of human pathogens?
2. How did Pasteur and Koch contribute to the understanding of the causes of infectious disease?
3. If you have a cold, what steps can you take to keep from spreading it to other people? Explain.
Typhoid Mary Video Questions
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1. What is typhoid? Tell what causes it, how it is spread and what its symptoms are.
2. When and where does the story take place?
3. How do they discover Mary’s role in the outbreak? Describe the detective work.
4. How do the doctors attempt to deal with Mary? Describe what they did to her.
5. Why do you think that she went back to cooking after they had told her not to?
6. How did Mary try to convince the authorities that she should be let go?
Stopping Malaria
Malaria is an infectious disease caused by the protist Plasmodium. This pathogen is transmitted from
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one person to another by a bite from a female mosquito. The disease infects more than 150 million people a
year and kills between 1.5 and 3.0 million people. Although malaria is treatable, it occurs in parts of the world
where effective treatments are largely unavailable. For this reason, the battle against the spread of malaria has
focused on prevention.
The diagram below provides information about the spread of malaria and the life cycle of the Anopheles
mosquito.
1. Diseases can be spread in four basic ways. In which of these ways is malaria spread?
2. Where does the female mosquito lay her eggs?
3. How does a Plasmodium get into the body of a female mosquito?
4. Sometimes swamps and shallow pools are drained to help prevent the spread of malaria. Use the diagram to
explain why this strategy is effective.
5. What are other ways you can think of to prevent the spread of malaria?
John Snow and the Cholera Epidemic
PART 1A. 1848–1849 Epidemic
In the early 19th century, medical statistics for England and Wales were carefully kept by the Office of the
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Registrar General of England and Wales. The physician, William Farr, published annual reports from this data
and recognized that this information could be used to learn about human illness. In the mid-19th century, cholera
epidemics were hitting London in waves. Cholera is a disease that is characterized by watery diarrhea, vomiting,
cramps, dehydration, and death. Farr and the physician John Snow set about using data collected about these
epidemics to find out what was causing the cholera in the hopes of preventing future epidemics. In the early
1800s, it was not known that microbes caused disease. John Snow’s first study of cholera was conducted in 1848
when an epidemic of cholera occurred in the area of Golden Square in London. At this time, most of the people
in London obtained their water from a community hand pump that drew water from a well from an underground
source. These communal pumps were usually located in a
square or on a street corner. People would bring buckets or containers and pump the water into the bucket and
carry it home for use by their families. To study the cholera epidemic, Snow acquired information about the
location of each
case and used this data to create a spot map. Refer to Figure 1, Distribution of Cholera Cases in the Golden Square
Area of London, August –September 1848 on the following page. This map is from Snow’s book, On the Mode
of Communication of Cholera, published in 1855. The circled X’s are the locations of the pumps that supplied
water to this area of London. Snow labeled three of these pumps, A, B, and C.
Using Snow’s spot map (Figure 1), answer questions 1-4:
1. What observations can you make about the distribution of the cholera cases?
2. Which well would you pick as the most likely source of contaminated water?
3. Why wouldn’t you identify pump C as a possible source?
4. What reasons could explain why there were no cases of cholera in the people living in the two-block area
around the brewery east of pump A?
PART 1B
Because of the clustering of cases around Public Water Pump A, Snow concentrated on this pump as the source
of the cause of the cholera. The absence of clusters around pumps B and C indicated that they were less likely to
be the source. Snow found that the water from pump B was so grossly contaminated that residents avoided it
and got
their water from pump A. Pump C was in a location that made it difficult for the majority of cases to use it.
5. What could Snow do to test his hypothesis that the epidemic was caused by water from Pump A? (Remember
that he couldn't actually test the water for bacteria.)
PART 1C
Snow went to the homes with cases of cholera and interviewed people about their source of drinking water. The
consumption of water obtained from pump A proved to be the one factor common among these cases. The
brewery workers got their water from a deep well on the premises and were also allotted a daily quota of beer so
they did not drink water from any of the pumps. Snow’s detailed study of the outbreak convinced the vestrymen
of the St. James parish of London to remove the pump handle from pump A, which stopped the cholera
epidemic.
6. What did John Snow do to prove that pump A was the source of the cholera?
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7. Compare this answer with your answer for question 5. How did your plan differ from what Snow actually
did?
Figure
PART 2
In the 1850’s London residents began to obtain their water in their homes rather than from communal pumps.
They signed up with one of the many water supply companies competing to supply home water. The water
intakes for the water supply companies were in a much polluted part of the Thames River. Sometime between
1849 and 1854, one of the companies, the Lambeth Company, moved its water source to an area of the Thames
where the water was relatively free from the sewage of London. In 1854, Snow noted that a terrible outbreak of
cholera occurred in a few square blocks of an area of London. “Within two hundred and fifty yards of the spot
where Cambridge Street joins Broad Street, there were upwards of five hundred fatal attacks of cholera in ten
days.” Snow wondered what the cause of this outbreak could be. Using data from the Office of the Registrar
General of England and Wales, Snow tabulated the
number of deaths from cholera in 1853-1854 according to the two water companies supplying the various subdistricts of London.
Table 2. Death Rates from Cholera, 1853-54
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By Water Company supplying sub-districts of London
District
Water Company
Population in 1851
Cholera Deaths
1852-1854
Cholera Deaths
per 100,000 people
1
Southwark &
Vauxhall
167,654
192
114
2
Lambeth
14,632
0
0
3
Both Companies
301,149
182
60
8. Refer to Table 2. Does this data support Snow’s hypothesis that polluted water causes cholera? Why or Why
not?
9. Is it conclusive proof that Snow’s hypothesis is correct? Why or why not?
10. What other factors might be causing the difference in cholera rates in the different London districts?
11. Design (briefly outline) an investigation that would confirm Snow’s hypothesis that polluted water, and not
some other factor, was causing the cholera epidemic?
Protecting the Herd Simulation
This worksheet will help you track the results of the disease transmission simulation.
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Simulation #1: 0% immune; 100% susceptible
Day Number of
Sick People
Number of
Immune People
Simulation #2 50% immune; 50% susceptible
Day
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
10
10
11
11
12
12
13
13
14
14
15
15
16
16
17
17
18
18
19
19
20
20
Number of
Sick People
Number of
Immune
People
Graph the spread of the disease in the two scenarios. Use two different color lines on the same graph to
represent to two scenarios.
Time Course of Class Epidemic
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0 1
2 3
4 5
6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Days
1. Why were the rates of infection so much lower in the second simulation?
2. Why didn’t all of the susceptible people in the second scenario get sick?
3. What would happen if schools stopped requiring vaccinations of students?
Measles Outbreak at Western High Discussion
It began with Naoko Yomata. She and her family had just moved when she started the second half of her
junior year at Western High in a small town in Washington State. One week into the semester, she had a sore
throat, felt exhausted, and devel-oped a fever of 102°F. Soon, she had a red rash all over her body—measles. Ten
days later, Caleb Miller and Jessica Johnson came down with measles. These students were in Naoko’s biology
class, and Jessica was her lab partner. The follow-ing week, a sophomore, Michael Chen, had measles and so did
the students’ biology teacher, Ms. Baker. The local public health officer was alarmed. Western High hadn’t had
a case of measles in 10 years, and now there were five cases in less than a month.
Naoko had just arrived in the United States from her home country, Japan, where she apparently contracted
measles. She had not been vaccinated as a child. Caleb was also susceptible to measles because his parents had
objected to vaccinations. Jessica and Michael were vaccinated when they were 15 and 18 months old,
respectively, but they had missed the required “booster shot” during elementary school. Ms. Baker was vaccinated
in 1966 when she was 5 years old. Later studies showed that the initial “killed measles” vaccine was not very
effective compared with the currently used “live measles” vaccine, first available in 1968. Ms. Baker was unaware
that her vaccination was not effective or that she needed a booster shot. The results of the public health officer’s
detective work explained why Naoko, Caleb, Jessica, Michael, and Ms. Baker got the measles. But there is another
question: In the 1950s and 1960s (before the measles vaccine was developed), most people got this disease as
preschool children or as elementary school students.
Biotechnology
Biotechnology is the use of living organisms or their products to modify human health and the human
environment. Although biotechnology was not used as a term until 1917, humans have been working with,
using and studying living organisms to modify their health and environments for thousands of years. Cut out
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the important events in the history of biotechnology and try to figure out where they go on the timeline. Don’t
glue them down until you check with your teacher to make sure they are all correct.
Before 1600
1800-1850
1850-1900
1900-1950
1950-1970
1970-1980
1980-1990
1990-2000
2000-Present
Tomatoes’ Tasteless Green Gene
Choosing tomatoes for color reduces fruit’s flavor, study finds
BY ROBERTA KWOK
The tomatoes your great-grandparents ate probably tasted little like the ones you eat today. The fruit used to
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have more flavor. A lot more flavor. In fact, tomatoes “were once so flavorful that you could take one in your
hand and eat it straight away just like we regularly eat apples or peaches,” according to plant scientist Alan
Bennett. He belongs to a team of international scientists who now think they know one reason why the fruit has
lost so much flavor.
Although some unripe tomatoes have a dark green patch near the stem, farmers
prefer that their unripe tomatoes are the same shade of green all over. The
consistent coloring makes it easier for them to know when the fruit should be
picked.
But tomatoes without the dark green patch are also missing an important
genetic ingredient that helps the fruit make more sugar and other tasty
molecules. So by breeding tomatoes for that consistent color, Bennett’s team
says, crop scientists may have accidentally contributed to also making this fruit
bland.
“It is a good illustration of unintended consequences,” Harry Klee told Science
News. Klee studies tomato flavor at the University of Florida in Gainesville.
Tomatoes make sugars in compartments called chloroplasts. Bennett, who works at the University of California,
Davis, and his colleagues found that tomatoes need the correct version of a particular gene (one called SlGLK2)
to form chloroplasts properly in the fruit. A gene acts as a biological instruction book that tells cells which
molecules to make.
Tomatoes without the dark green tinge have the wrong version of this gene, the researchers report in the June 29
issue of Science. As these fruit ripen, they can’t make as many chloroplasts. And chloroplasts that they do
produce are smaller. One result: The tomatoes make less sugar — and don’t taste as good.
Tomatoes also produce gases responsible for some of the odors we associate with the fruit. Even though you
only breathe them, these gases affect the way that you perceive flavor. Tomatoes with weak chloroplasts can’t
make as much of these gases, further reducing flavor.
But the newfound gene change is “not the whole story of why modern tomatoes are so bad, by a long shot,”
Klee told Science News. Tomatoes also taste blander when they are picked too early or stored in the fridge.
Write your opinion on tomatoes. Do you think this genetic engineering is a good thing or a bad thing? What
about both? Be thorough and clear with your opinion.
Biotechnology Webquest
Cloning: http://learn.genetics.utah.edu/content/tech/cloning/clickandclone/
1. What are the roles of the three different mice that are used in the cloning experiment.
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2. What part of the somatic cell is removed? Why is that part of the cell important for cloning?
3. Did this happen in real life? If so, where did it happen?
4. Why was the baby mouse brown, and not black or white?
5. Do you think this experiment is ethical? Why or why not?
DNA Fingerprinting: http://www.pbs.org/wgbh/nova/education/body/create-dna-fingerprint.html
Read the introductory paragraph and then click “VIEW” to start the activity.
6. What is a DNA fingerprint? What are they used for?
7. What “crime” was committed? What bodily fluid was removed from the “crime scene” to get DNA?
8. What is a restriction enzyme? What does it do?
9. What is gel electrophoresis? What is it used for?
10. Smaller fragments of DNA move __________________________ than longer strands
11. What are probes? What do they attach themselves to? What are they used for?
12. Based on the DNA fingerprint, who licked the lollipop? Explain how you know this.
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Genetic Engineering: http://www.iptv.org/exploremore/ge/uses/index.cfm 8 categories of uses for genetic
engineering are identified on the left side of the page. Choose three to read about and summarize below. Write at least 5
sentences about each category.
13. Category:
14. Category:
15. Category:
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