Download viruses - Images

Bellwork - MONDAY
Draw the shape of a plant and animal cell.
 Draw the mitochondria, nucleus & Golgi
body

Vocabulary Words – QUIZ WED.
1.
2.
3.
4.
5.
6.
7.
8.
Virus
Host
Parasite
Bacteriophage
Bacteria
Asexual
reproduction
Sexual
reproduction
Vaccine
Endospore
10. Decomposer
11. Infectious disease
12. Toxin
13. Antibiotic
14. Antibiotic
resistance
15. Vector
16. Pathogen
9.
Words to add to your vocabulary list

Vector – organism that spreads pathogens
from one host to another

Pathogen – an agent that causes disease
Bellwork

Tuesday


Describe the functions of the mitochondria,
nucleus, cell membrane and cell wall
Have your vocabulary foldable on your desk
Viruses, Bacteria,
& Fungi
3.c. Describe how viruses, bacteria, fungi,
and parasites may infect the human body and
interfere with normal body functions (DOK 1)
3.g. Research and draw conclusions about the
use of single-celled organisms in industry, in
the production of food, and impacts on life
(DOK 3)
VIRUSES: WHAT IS A VIRUS?
A tiny, non-living particle that enters into
a living cell and then reproduces inside
that cell.
 No organisms are safe from viruses


From the smallest bacterial cell to the tallest
tree, from your pet cat to your younger
brother

There is a virus able to invade that organisms cells.
CHARACTERISTICS OF VIRUSES
Do not have all characteristics essential
for life.
 Are not cells
 Do not use their own energy to grow or to
respond to their surroundings
 VIRUSES CANNOT MOVE ON THEIR OWN!
 **The only way viruses are like organisms
is that they are able to multiply.

A HOST
An organism that provides a source of
energy for a virus or another organism
 A virus enters and multiplies inside a host


VIRUSES CAN ONLY MULTIPLY WHEN THEY
ARE INSIDE A LIVING CELL
A PARASITE

An organism that lives on or in a host and
causes it harm

A virus acts like a parasite

Almost all viruses destroy the cells in
which they multiply
VIRUS SHAPE

Bacteriophage: a virus that infects
bacteria


Its name means “bacteria eater”
Has a complex, robot like shape
Round
 Rod
 Bullet shaped

VIRUS SIZES

Vary in sizes

Smaller than cells

Smaller than bacteria

Cannot be seen with a regular microscope
THE STRUCTURE OF VIRUSES


All viruses have very similar structures
even though they look very different
2 basic parts:
1.
2.
A protein coat that protects the virus
An inner core made of genetic material

A virus’s genetic material contains the instructions
for making new viruses.
***VIRUSES DO NOT HAVE A CELL WALL!
PROTEINS ON THE SURFACE
OF A VIRUS
Play an important role during the invasion
of a host cell
 Each virus contains unique surface
proteins
 The shape of the surface proteins allows
the virus to attach to certain cells in the
host

LOCK AND KEY ACTION
Because the lock and key action of a virus
is highly specific, a certain virus can
attach only to one or a few types of cells.
For example, most cold viruses infect cells
only in the nose and throat of humans

HOW VIRUSES MULTIPLY
Once inside a cell, a virus’s genetic
material takes over many of the cells
functions.
 It instructs the cell to produce the virus’s
proteins and genetic material.
 These proteins and genetic material then
assemble into new viruses.



Some viruses take over cell functions
immediately
Other viruses wait for a while
ACTIVE VIRUSES
An active virus immediately goes into
action.
 The virus’s genetic material takes over cell
functions, and the cell quickly begins to
produce the virus’s proteins and genetic
material
 Then these parts assemble into new
viruses
 When the cell is full of viruses, it bursts
open, releasing hundreds of new viruses
as it dies

HIDDEN VIRUSES








Hidden viruses do not immediately become active
They “hide” for awhile
The genetic material becomes part of the cell’s genetic
material
The virus does not appear to affect the cell’s functions and
may stay inactive for years
Each time the host cell divides, the virus’s genetic material
is copied along with the host cell’s genetic material
Then, under certain circumstances, the virus’s genetic
material becomes active
It takes over the cells functions in the same way that active
viruses do
Soon, the cell becomes full of viruses and bursts open
 For example: virus that causes cold sores
Vector

An organism that spreads pathogens from
one host to another

Examples:




A
A
A
A
mosquito infected with malaria
raccoon infected with rabies
person infected with the flu
tick infected with Lyme Disease
BACTERIA








Discovered by Anton van Leeuwenhoek when he
was looking at his tooth under a microscope
Single-celled organisms
They are prokaryotes
Genetic material in their cells is not contained in
a nucleus
Lack nucleus
Have a cell wall that protects the cell
Genetic material is found in the cytoplasm
Genetic material forms a circular shape
BACTERIA CONTINUED

May have a flagellum that helps it to move

Flagellum spins in place like a propeller to
allow the cell to move

Bacteria can have many flagella, one, or none

Bacteria that do not have flagella must rely on
other methods for movement
SHAPE OF BACTERIA

3 basic shapes:
1.
2.
3.

Spherical (circular)
Rod
Spiral
The chemical makeup of the cell wall
determines the shape
SIZE OF BACTERIA

Vary greatly in size

Larger than viruses but still very small
OBTAINING FOOD AND
ENERGY

All bacteria need certain things to survive

Bacteria must have a source of food and a
way of breaking down the food to release
its energy
OBTAINING FOOD

Autotrophs: make their own food
1.
2.
Some capture and use the sun’s energy as
plants do
Others, such as bacteria that live deep in
mud, use energy from chemical substances in
their environment
OBTAINING FOOD CONT’D

Heterotrophs: cannot make their own food

Must consume other organisms or the food
that other organims make

May consume a variety of food

Milk, meat, decaying leaves, etc.
RESPIRATION
Process of breaking down food to release
its energy
 Bacteria need a constant supply of energy
to carry out their functions
 Most bacteria need oxygen to break down
their food, but a few do not need oxygen
for respiration


For those bacteria, oxygen kills them
REPRODUCTION




When bacteria have plenty of food, the right
temperature, and other suitable conditions, they
thrive and reproduce frequently
Under ideal conditions, some bacteria can
reproduce as often as every 20 minutes!
It’s a good thing that growing conditions for
bacteria are rarely ideal
Otherwise, there would be no room on Earth for
other organims

Bacteria would take over everything!
REPRODUCTION

There are 2 types of reproduction
1.
2.
Asexual reproduction
Sexual reproduction
1. ASEXUAL REPRODUCTION


Reproductive process that involves only one
parent and produces offspring that are identical
to the parent
Bacteria reproduce by a process called binary
fission, in which one cell divides to form two
identical cells



Binary fission is a form of asexual reproduction
During binary fission, a cell 1st duplicates its
genetic material and then divides into 2 separate
cells
Each new cell gets its own complete copy of the
parent cell’s genetic material
2. SEXUAL REPRODUCTION
Involves 2 parents who continue their
genetic material to produce a new
organism, which differs from both parents
 Some bacteria may undergo a simple form
of sexual reproduction
 During a process called conjugation, one
bacterium transfers some of its genetic
material into another bacterium through a
thin, threadlike bridge that joins the two
cells

2. SEXUAL REPRODUCTION
CONTINUED
After the transfer, the cells separate
 Results in bacteria with new combination
of genetic material
 Conjugation does not increase the number
of bacteria



However, it does result in new bacteria that
are genetically different from the parent cells
The bacteria will then divide by binary
fission and the new genetic material is
passed to the new cells
ENDOSPORE FORMATION

A small, rounded, thick-walled, resting cell
that forms inside a bacterial cell


Contains the cell’s genetic material and some
of its cytoplasm
Sometimes, conditions in the environment
become unfavorable for the growth of
bacteria

For example, food sources can disappear,
water can dry up, or the temperature can fall
or rise dramatically
ENDOSPORE FORMATION
CONTINUED


Some bacteria can survive harsh conditions by
forming endospores
Endospores can resist freezing, heating, and
drying



Endospores are also light


Can survive many years
For example: the bacteria that causes botulism produces
heat-resistant endospores that can survive in improperly
canned foods
Can be transported by a light breeze
If an endospore lands in a place where conditions
are suitable, it opens up and the bacteria can
begin to grow and multiply
Bellwork

Wednesday – make sure you write the
question.
1.
2.
3.
4.

Are viruses considered cells?
Can viruses move on their own?
Do viruses use their own energy?
Name the 4 shapes of viruses.
Study for your vocabulary quiz.
Answer questions in notes when
finished - do not write question
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
T/F: Not all organisms can get a virus.
T/F: Viruses have all characteristics that
are essential for life
Are viruses cells?
Do viruses use their own energy?
T/F: Viruses must be in a host cell in order
to multiply
T/F: A virus acts like a parasite.
What is located on the outer coat of a virus
that is specific to that virus?
Are viruses considered living organisms?
Can viruses move on their own?
Do viruses have the ability to multiply?
Bellwork

Thursday








Give an example of a vector.
Name the 4 shapes a virus.
What is on the surface of a virus?
Do viruses have a cell wall?
Turn in bellwork – you should have Monday,
Tuesday, Wednesday, and Thursday
Turn in writing prompt
MAKE SURE YOUR NAME IS ON EVERYTHING!
STUDY YOUR NOTES!
Classwork

Use 2 column note-taking strategy to take
notes on the following:





Usefulness of bacteria – pages 168 – 171
How disease spreads – pages 174 – 175
Treating disease – pages 176 – 178
Preventing disease – page 179
YOU WILL HAVE A QUIZ TOMORROW ON THIS
INFORMATION.
Bellwork – FRIDAY
Which of these would happen to the cell
if cellular respiration stopped?
A. It would not have the energy it needs to perform
its functions.
B. It would grow larger because it would not be
able to dispose of wastes.
C. It would have to access backup energy trapped
in the chemical bonds of food.
D. It would no longer be able to passively transport
materials across its cell membrane.

ONCE YOU FINISH BELLWORK….LOOK OVER
YOUR NOTES!!!
Usefulness of viruses

Viruses are not all bad…

They can be used in a technique called gene
therapy.
Usefulness of bacteria
1.
2.
3.
Oxygen and food production
Environmental recycling and cleanup
Health maintenance and food production
Oxygen and Food Production
Autotrophs release oxygen into the
atmosphere
 Bacteria grow in milk to produce dairy
products such as buttermilk, yogurt, sour
cream, and cheeses
 Bacteria grow in apple cider change the
cider into vinegar
 Can bacteria in food production be
harmful?

Environmental Recycling

Decomposers




Heterotrophic bacteria
Organisms that break down large chemicals in
dead organisms into smaller chemicals
Nature’s recyclers
They return basic chemicals to the
environment for other living things to reuse

Example: leaves of many trees die in autumn and
drop to the ground, decomposing bacteria spend the
next month breaking down the chemicals in the dead
leaves, the broken down chemicals mix with the soil
and can then be absorbed by the roots of nearby
plants.
Environmental Cleanup

Some bacteria eat oil


They convert the poisonous chemicals in oil
into harmless substances
Scientists have put these bacteria to work
cleaning up oil spills in oceans and gasoline
leaks in the soil under gas stations
Health and Medicine

Did you know that many of the bacteria living in your body
actually keep you healthy?

In your digestive system, your intestines teem with
bacteria to help you digest food, make vitamins, or
compete for space with disease-causing organisms
preventing the harmful bacteria from attaching to your
intestines and making you sick

Some bacteria help make medicines
 Human insulin
Viruses, Bacteria, and
Your Health
How Infectious Disease Spread




Have you ever wondered how you “catch” a cold, strep
throat, or the chickenpox?
These and many other diseases are called infectious
diseases – illnesses that pass from one organism to another
Infectious diseases can spread through contact with an
infected person, a contaminated object, an infected animal,
or an environmental source.
Once contact occurs, disease causing agents, such as
viruses and bacteria, may enter a person through breaks in
the skin, or they may be inhaled or swallowed
 Others may enter the body through the moist linings of
the eyes, ears, nose, mouth, or other body openings
Contact With An Infected Person

Direct contact such as touching, hugging,
or kissing an infected person can spread
some infectious diseases


Kissing an infected person can transmit cold
sores
Contact can also occur indirectly


A common form of indirect contact is inhaling
the tiny drops of moisture that an infected
person sneezes or coughs into the air
These drops of moisture may contain disease
causing organisms, such as flu or cold viruses
Contact With A Contaminated
Object

Certain viruses and bacteria can survive for a while outside
a person’s body

They can be spread via objects such as eating utensils
 Drinking from a cup used by an infected person can
spread diseases such as strep throat and mononucleosis

If you touch an object that an infected person has sneezed
or coughed on, you may transfer some viruses and bacteria
to yourself if you then touch your mouth or eyes

You may also get sick if you drink water or eat food that an
infected person has contaminated
Contact With An Infected Animal
Animal bites can transmit some serious
infectious diseases to humans
 For example:




Rabies can be transferred through the bite of
an infected dog, raccoon, or some other
animal
Tick bites can transmit the bacteria that cause
Lyme Disease
Mosquitoes can spread the virus that causes
encephalitis, a serious disease in which the
brain tissues swell
Contact With Environmental
Sources

Certain viruses and bacteria live naturally
in food, soil, and water

Poultry, eggs, and meat often contain
salmonella bacteria
Eating foods that contain these bacteria
can lead to one type of food poisoning
 Cooking the foods thoroughly kills the
bacteria

Treating Infectious
Disease
Bacterial Diseases

Many bacterial diseases can be cured with
medications known as antibiotics

A chemical that can kill bacteria without
harming the person’s cells
Antibiotics are made naturally by some
bacteria and fungi
 Antibiotics such as penicillin are made in
large quantities in factories


Penicillin works by weakening the cell walls of
bacteria and causing the cell to burst
Bacterial Disease Continued
If you have ever had strep throat, you
know that the infection makes swallowing
feel like your throat is full of barbed wire.
But soon after you begin taking the
antibiotic, your throat feels better
 The antibiotic quickly kills the bacteria
that cause strep throat
 Since antibiotics attack cell walls, they
only work on bacteria.


Viruses do not have cell walls
Antibiotic Resistance
Results when some bacteria are able to
survive in the presence of an antibiotic
 Antibiotics are less effective today than
they once were because over the years,
many bacteria have become resistant to
antibiotics

Example of Antibiotic Resistance






The recent increase in tuberculosis cases demonstrates the
impact of antibiotic resistance
As patients began to take antibiotics to treat tuberculosis in
the 1940s, the number of tuberculosis cases dropped
significantly.
Unfortunately, there were always a few tuberculosis
bacteria that were resistant to the antibiotics
As resistant bacteria survive and reproduce, the number of
resistant bacteria increases.
The number of tuberculosis cases has increased over the
last 20 years
Today, antibiotic resistance is a serious problem and some
bacterial diseases are becoming difficult to treat
Viral Diseases

Unlike with bacterial diseases, there are
currently no medications that can cure
viral infections


Viruses do not have a cell wall and since
antibiotics attack the cell wall, they are not
effective in curing viruses.
However, many over the counter
medications can help relieve symptoms



Available without a prescription
May make you feel better, but can also delay
your recovery if you resume your normal
routine while you are still sick
They can also hide symptoms that would
normally prompt you to go to a doctor
Viral Diseases Continued
The best treatment for viral infections is
often bed rest
 Resting, drinking lots of fluids, and eating
well-balanced meals may be all you can
do while you recover from a viral disease

Preventing Infectious
Diseases
Vaccines





A substance introduced into the body to stimulate
the production of chemicals that destroy specific
viruses or bacteria
May be made from dead or altered viruses or
bacteria
Because they are dead or altered, the viruses or
bacteria in the vaccine do not cause disease
Instead, they activate the body’s natural
defenses, the vaccine puts the body “on alert” so
if that virus or bacteria ever invades the body, it
is destroyed before it can cause disease
You may have been vaccinated against diseases
such as polio, measles, tetanus, and chickenpox
Other ways to prevent infections
Eat nutritious food
 Get plenty of sleep
 Drink plenty of fluids
 Exercise
 Washing your hands often
 Do not share eating or drinking utensils
 Storing food properly
 Keeping kitchen equipment and surfaces
clean
 Cooking meats well

Homework
1.
2.
3.
4.
5.
How are bacteria beneficial as decomposers in
the soil?
What kind of bacteria help provide oxygen for
breathing?
What role do bacterial decomposers play in the
environment?
A friend states that all bacteria are harmful to
people. List three reasons why this statement is
inaccurate.
In what ways might bacteria contribute to the
success of a garden in which pea plants are
growing?
Bellwork - MONDAY

Look over your notes when you finish
answering the question.
INFECTIOUS DISEASES
You will need to copy everything
on the infectious disease slides.
LYME DISEASE - bacteria

Symptoms:


How it spreads:


Bite of an infected deer tick
Treatments:


Rash at site of tick bite; chills; fever; body
aches; joint swelling
Antibiotic
Prevention:

Tuck pants into socks; wear a long-sleeved
shirt
TUBERCULOSIS (TB) – bacteria

Symptoms:


How it spreads:


Inhaling droplets
Treatment:


Fatigue; mild fever; weight loss; night sweats;
cough
Antibiotic
Prevention:

Avoid contact with people with an active
infection; vaccine (for those at high risk)
TETANUS (LOCKJAW) – bacteria

Symptoms:


How it spreads:


Deep puncture wound
Treatment:


Stiff jaw and neck muscles; spasms; difficulty
swallowing
Antibiotic; opening and cleaning the wound
Prevention:

Vaccine
STREP THROAT – bacteria

Symptoms:


How it spreads:


Inhaling droplets; contact with a contaminated
object
Treatment:


Fever; sore throat; swollen glands
Antibiotic
Prevention:

Avoid contact with infected people; do not
share utensils, cups, or other objects
FOOD POISONING – bacteria

Symptoms:


How it spreads:


Eating foods containing the bacteria
Treatment:


Vomiting; cramps; diarrhea; fever
Antitoxin medicines
Prevention:

Properly cooking and store foods; avoid foods
in rusted and swollen cans
INFLUENZA (FLU) – virus

Symptoms:


How it spreads:


Contact with contaminated objects; inhaling
droplets
Treatment:


High fever; sore throat; headache; cough
Bed rest fluids
Prevention:

Vaccine
HEPATITIS C – virus

Symptoms:


How it spreads:


Contact with the blood of an infected person
Treatment:


Oftentimes no symptoms; jaundice (yellowing
of the eyes and skin); fatigue
Drugs to slow viral multiplication; there is no
cure
Prevention:

Avoid contact with infected blood
CHICKENPOX – virus

Symptoms:


How it spreads:


Contact with the rash; inhaling droplets
Treatment:


Fever; red, itchy rash
Antiviral drug (for adults)
Prevention:

Vaccine
ACQUIRED IMMUNODEFICIENCY
SYNDROME (AIDS) – virus

Symptoms:


How it spreads:


Sexual contact; contact with blood; pregnancy, birth,
and breastfeeding
Treatment:


Weight loss; chronic fatigue; fever; diarrhea; frequent
infections; weakening of immune system
Drugs to slow viral multiplication; there is no cure
Prevention:

Avoid contact with infected body fluids
SMALLPOX – virus

Symptoms:


How it spreads:


Coming into contact with an infected person
Treatment:


Fever, backache, diarrhea, vomiting, fatigue,
pink rash
There is no drug to treat smallpox
Prevention:

Vaccine
DYSENTERY - ameoba

Symptoms:


How it spreads:


Drinking contaminated water
Treatment:


Extreme diarrhea, vomiting, stomach pains,
fever
Antibiotic
Prevention:

Drinking clean water
You will need to know the shapes of the
viruses/bacteria that cause the following diseases
Tuberculosis: rod shaped bacteria
 Lyme disease: rod shaped bacteria
 Cholera: rod shaped bacteria
 AIDS: round virus
 Flu: round virus
 Smallpox: round virus
 Dysentery: amoeba

FUNGUS
classifies all mushrooms, mildews, yeasts,
and molds.
 Examples of Fungi - bread molds, yeast,
mushrooms
 Diseases caused by Fungi - Athlete's foot
and Ring worm

Fungal Diseases
1.
Athlete’s Foot:



2.
Scaling, flaking, itchy skin
Person to person – contact with the fungus
Treated with antifungal creams
Ring Worm:



Itchy, red, scaly, raised patches on skin (in
shape of a ring)
Fungal spores land on a person’s skin and
begin to grow on surface
Treated with antifungal creams