Download Virus & Bacteria PPt Notes

Warm-Up!!! 3/19
B = blue hair
b = purple hair
Cross Bb and bb.
What is the chance they will have a child
with purple hair?
Warm-Up!!! 3/19
B = blue hair
b = purple hair
Cross Bb and bb.
What is the chance they will have a child
with purple hair?
50%
Warm-Up!!! 3/20
E = purple eyes
e = orange eyes
What is the chance a heterozygous father
and a homozygous dominant mother
have a child with orange eyes?
Warm-Up!!! 3/20
E = purple eyes
e = orange eyes
What is the chance a heterozygous father
and a homozygous dominant mother
have a child with orange eyes?
0%
Warm-Up!!! 3/21
Which of the compounds below are the
products of Photosynthesis and which
are the products of Respiration?
Carbon Dioxide
Oxygen
ATP
Water
Glucose
Warm-Up!!! 3/21
Which of the compounds below are the
products of Photosynthesis and which
are the products of Respiration?
Photosynthesis
Products:
Oxygen
Cellular Respiration
Products:
ATP
Sugar
Carbon Dioxide
Water
The Black Death
The Amazing
World of
Bacteria!!!!
Compare/Contrast
Prokaryotes (Bacteria)
Eukaryotes
Smaller
Simpler
Has genetic material
No nucleus
Grow, reproduce, &
respond to environment
Some move by gliding
or swimming
Some have internal
membranes
Unicellular
Larger
Complex
Has genetic material
Nucleus
Grow, reproduce, &
respond to environment
All move
Have internal membranes
Unicellular & multicellular
Has organelles & cytoplasm
Bacteria are:
•Unicellular
•Prokaryotic…which means?
Each square centimeter of your
skin averages about 100,000
bacteria. A single teaspoon of topsoil
contains more than a billion
(1,000,000,000) bacteria.
Fact:
Bacterial Kingdoms!
Bacteria are ALWAYS Unicellular
Prokaryotes (NO Nucleus)!
There are two Kingdoms of Bacterial Life:
1. Archaebacteria – cell walls without
Peptidoglycan. Very old and live in
extreme environments
2. Eubacteria – cell walls with
Peptidoglycan. The bacteria that infect
us!
Bacteria Contain:
1.
2.
3.
4.
5.
A Cell Wall
Circular DNA
Tiny Pieces of DNA called plasmids
Ribosomes for making protein
Flagella for movement (sometimes)
Bacteria Reproduce:
Asexually through a
process called
Binary Fission.
This results in two
identical
daughter cells
(clones).
Conjugation
A process bacteria go
through to share DNA.
Bacteria don’t exchange
their entire DNA just
the small plasmid rings.
This is how they share
genetic info and become
antibiotic resistant.
Botulism Toxin
Identifying Bacteria!
Bacteria are very small, much smaller
than a single human cell, but they can
be identified by their:
1. Shape
2. Arrangement
3. The way they obtain food/energy
Bacteria Shapes!
Bacteria have three
main shapes!
1. Bacilli: Rod-shaped
2. Cocci: Spherical
3. Spirilla: Cork-screw
shaped
How we Identify Prokaryotes
• The chemical nature of their cell walls.
• A method of Gram Staining is used to
determine nature. Gram (+) = violet, Gram
(-) = pink.
Bacterial Arrangements
Those three shapes of bacteria can come
in three different arrangements:
1. Pairs of two:
2. In Chains:
3. In Clusters:
prefix diploprefix streptoprefix staphylo-
Bacterial Arrangements
So, if you looked under a microscope
and found a spherical bacteria in
pairs of two what would you call it?
Bacterial Arrangements
So, if you looked under a microscope
and found a spherical bacteria in
pairs of two what would you call it?
Diplococcus!
What about a spherical bacteria in
chains?
Bacterial Arrangements
What about a spherical bacteria in
chains?
Streptococci or Streptococcus
bacteria!
Bacterial Arrangements
What about a rod shaped bacteria in
chains?
Bacterial Arrangements
What about a rod shaped bacteria in
chains?
Streptobaccili!
Bacteria Metabolism
Bacteria are much more diverse than
we are in their ways of obtaining
energy. Some make their own food
(autotrophs) and some must obtain
energy from outside sources
(heterotrophs).
1. Hetereotrophic Bacteria
These bacteria eat others/food.
A. Decomposers – eat and recycle
organic material
B. Pathogens – parasites. They either
attack cells directly or secrete
toxins that damage cells
C. Nitrogen Fixing Bacteria – turn
atmospheric nitrogen into a form
life can use.
2. Autotrophic Bacteria
These bacteria make
their own food.
A. Photoautotrophs use the sun’s energy
to make food.
B. Chemoautotrophs –
Obtain energy from
molecules like
ammonia or sulfur
dioxide
Nitrogen fixing bacteria
in the nodules of roots
Helpful Bacteria
• Decomposers break down dead organic material
• Biotechnology - inserting helpful genes into a
plasmid
• Bioremediation - bacteria eat up oil spills
• Food production – cheese and yogurt
• Put nitrogen back into the soil
• Aid in digestion
Strep throat
Streptococcus
Staphylococcus
Syphilis
Gonorrhea-Passed from Mother to
Baby
• work by preventing cell wall
formation, breaking up cell
membranes, or disrupting
chemical processes.
•cannot treat viral infections.
Interdependence
Viruses and
organisms rely
on their
environment
and other
species for survival.
Viruses
Viruses are NOT cells. A virus
is an infectious agent made up
of:
•a core of nucleic acid (RNA or DNA)
•a protein coat
Alive or not?
Even scientists disagree as to
whether or not viruses are
alive. What do you think? Look
at the chart on the next page
to help you decide.
Characteristic
of life
CELL
VIRUS
Made of cells
YES
NO
Obtain & use
energy
YES
NO
Grow & develop
YES
Reproduce
YES
Respond &
adapt
Contain RNA or
DNA
Only inside a
living cell
Only inside a
living cell
YES
YES
YES
YES
Viruses
• Viruses are particles of:
– Nucleic acid
– Protein
– Lipids (only in some)
• They vary in size and structure.
• They enter living cells & use the machinery of
the infected cell to produce more viruses.
• Composed of:
– A core DNA or RNA (which has the instructions
for making copies)
– This is surrounded by a protein coat called a
capsid which binds the virus to the surface of the
host cell.
Structure
of a virus
ENVELOPE
• Envelope (part of
the protein coat)
• Capsid (part of
the protein coat)
• Nucleic acid
(either DNA or
NUCLEIC
RNA)
ACID
CAPSID
Viruses
Retroviruses
– contain RNA as their genetic information.
– Genetic information is copied backwards.
– It may remain dormant for any length of time
before becomes active and it can cause death
of the host cell.
– Ex. AIDS, some cancers.
Retrovirus
ENVELOPE
• A virus that
contains RNA
instead of DNA
• Human
RNA
Immunodeficiency
Virus (HIV) is a
retrovirus
• HIV causes AIDS
CAPSID
Viruses
• Bacteriophages– Viruses that infect bacteria.
– Ex. Bacteriophage T4
Bacteriophage
• A virus that
only infects
bacteria
CAPSID
HEAD
DNA
CAPSID
TAIL
FIBER
Lytic Cycle
The viral infection that
rapidly kills the host cell is
the lytic cycle.
Cycle Illustration
1
2
4
3
5
Lysogenic Cycle
The viral infection that enters
a cell, remains harmless for a
period of time (sometimes
years), and then becomes
harmful later is called the
lysogenic cycle.
Viruses
• Once inside a host cell:
– Lytic infection
• Virus inters cell and makes copies of itself.
• Causes cell to burst, releasing new virus particales that
can attack other cells.
• It then uses materials of host cell to make copies of its own
DNA molecule.
• Host cell is destroyed.
– Lysogenic infection
• Virus integrates its DNA into the DNA of host cell.
• The viral genetic info. replicates along with the host cell’s
DNA.
• Viral DNA that’s embedded in host’s DNA is called
prophage.
• Unlike lytic, it does not lyse the host cell right away so it
may remain a part of DNA of host for many generations.
Viruses
• Must infect living cells in order to
reproduce.
• Are Parasites.
• Are not considered to be living things
because they are not made up of cells &
cannot live independently.
Role of viruses
• All viruses act like parasites, harming
the host cell.
• Viruses cause disease in every kind of
organism—animals, plants, fungi,
protists, and bacteria.
Jenner and Pasteur
• Edward Jenner, English Doctor….
– Invented vaccine
– Infected own son with cow pox (a mild
form of small pox)
– Son didn’t contract small pox
– Cow pox triggered immune system to
create an immunity against small pox
• Louis Pasteur
–Pasteurization
–Disproved spontaneous generation
–Said “life came from life”
–Boiled broth to kill microorganisms
What is an epidemiologist?
• A scientist who studies the causes and
controls of disease outbreaks.
• Involved in preventing disease outbreaks
and in stopping outbreaks that do occur
spreading.
• Work for CDC, FBI, etc.
Inoculation & Incubation of culture
medium
• Culture medium – either a broth or an
agar with nutrients added to it to aid in the
growth of microorganisms.
• Inoculation – referred to as a streak or
stab (putting microorganisms in a nutrient
agar or broth so they can grow)
• Incubation – usually 24 – 48 hours at a
temperature of 20º C or 37º C.
Inoculation Technique
Heat loop
Inoculation
Inoculation Broth
Inoculation Slant
Agar Deep
Agar Plate
Above are Petri Dishes with
Agar that are used to culture
bacteria.
Streak Plates
Bacteria cultures – each color is a
different types of bacteria.
Finished Product
How to Capture Bacteria
1. Decide what you want to swab as a team
2. Wet the swab by dipping it in the beakers
of water up front
3. Swab your location (door knob, key board,
etc.)
4. Come to the front and run the swab lightly
over your group’s section of the petri dish.
5. Label what location your group swabbed on
the sheet.
6. Through the swab away and wash your
hands!!!!
1. What are the different ways bacteria obtain
energy?
2. What are the characteristics of Prokaryotes?
3. Name and describe/draw the three different
arrangements of bacteria.
4. What are some ways bacteria are helpful to
humans?
5. Name and describe the process of how
bacteria reproduce.
6. Describe the 2 Kingdoms of bacteria and
describe how they differ?
7. Name and describe the three different
shapes of bacteria.
8. Draw and label the parts of a bacterium
Pathogen – disease causing
organisms
• Virus
• Bacteria
• Fungi
• Protozoans
Koch’s Postulates
1. The pathogen must be found in an
animal with the disease and not in a
healthy animal.
2. The pathogen must be isolated from the
sick animal and grown in a laboratory
culture.
3. When the isolated pathogen is injected
into a healthy animal, the animal must
develop the disease.
4. The pathogen should be taken from the
second animal and grown in a laboratory
culture. The cultured pathogen should
be the same as the original pathogen.
Bacteria produce disease in 2
ways:
• Bacteria damage the cells & tissues of
the infected organism directly by
breaking down the cells for food.
• Bacteria release toxins (poisons) that
travel throughout the body interfering
with the normal activity of the host.
Bacterial Diseases
• Louis Pasteur – the first to show that bacteria
caused diseases and established the germ
theory of disease.
• Diseases:
– Tuberculosis- bacteria is inhaled into lungs which
destroys tissue and gets into the blood to travel
to other places throughout the body.
– Strep Throat- bacteria releases toxins. This bacteria
also causes scarlet fever.
– Diphtheria- infects tissues of the throat which leads to
breathing problems, heart failure, paralysis & death.
– Lyme Disease
– Tooth Decay
Some Bacterial Diseases
VIRAL DISEASES
Viral Diseases
• Viruses disrupt the body’s normal
equilibrium.
• Viruses attack & destroy certain body cells
causing the symptoms of the disease.
• Diseases:
–
–
–
–
–
Common cold
Influenza
AIDS
Chickenpox
Measles
• Can produce other serious diseases in both animals & plants.
• Plant viruses have a difficult time entering cells they
infect partly because plant cells have though cell walls.
Viral Diseases
• 2 Virus like particles can cause disease:
• Viroids – single-stranded RNA molecules that have
no surrounding capsoid. (cause disease in plants).
– Ex. Tobacco mosaic virus.
• Prions – particles that contain only protein which
have no DNA or RNA. (cause disease in animals &
humans).
– Ex. Foot & mouth disease in livestock.
MEASLES
SMALLPOX
HERPES
HIV
• HIV is transmitted when the body fluids of
an infected individual are passed on to an
uninfected individual by direct contact or
contaminated objects.
• Breaks down immune system, so can no
longer fight off disease
– Hides in Helper T cells
• People w/HIV, then AIDS suffer from two
rare problems.
– Pneumosystis carinii – protozoan
infections of lungs
– Kaposi’s sarcoma - cancer
How is disease spread?
• People – Direct contact
–Touching
–Kissing
–Sexual contact
• Object – food poisoning
• Air, Soil and Water
• Vectors – insects: malaria
Prevention & Control
• Methods of controlling bacterial growth:
– Sterilization – heat; most can’t survive high
temperatures for long period on time.(kills
bacteria)
– Disinfectants – soaps & cleaning solutions;
sterilizes hospitals; overuse may cause bacteria
to evolve.(kills bacteria)
– Food storage – refrigeration (bacteria takes longer
to multiply at low temperatures); boiling; frying;
steaming.
– Food processing – canning (heated to high
temperature, placed into sterile jars & sealed);
chemical treatments such as salt, vinegar,sugar.
(kills bacteria)
Protection Against
• Vaccines – prevention.
• Antibiotics – viruses do not respond to
antibiotics but sometime the symptoms
can be treated.
Allergies
• Occur when antigens bind to
mast cells.
• Activate mast cells which
release histamines.
–Histamines produce sneezing,
runny eyes & nose
Common Antigens that cause
allergies
• Foods
• Dust
– Milk, eggs
• Antibiotics
– Penicillin
• Cosmetics
• Pollen
• Molds
• Microbes
• Chemicals in plants – poison ivy
Autoimmune diseases
• A disease in which the immune system
starts attacking body cells as if they were
pathogens.
• Affect organs and tissues in different parts
of the body.
• Graves disease, Multiple sclerosis (MS),
Rheumatoid arthritis, Systemic lupus
erythematosus (SLE), Type I diabetes
Some Autoimmune Diseases
• Rheumatoid Arthritis – exact cause is unknown,
but clear the immune system is involved.
– Involves inflammation of joint, swelling,
pain & loss of function.
• Rheumatic Fever – happens when
streptococcus bacteria causes a disease
known as strep throat.
– If left untreated, the immune system
produces antibodies that destroy
bacteria.
• Multiple sclerosis – result of destruction
by immune system of special cells that
surround nerve fibers and permit rapid
impulse transmission.
Autoimmune diseases, cont.
• Lupus – exact cause unknown, although it is
certain that both environment & genetic factors
are involved.
– Believed a genetic pre-disposition to the
disease
• Symptoms include:
– Achy joints, 100°F + fever, Arthritis,
Prolonged or extreme fatigue, Skin rashes,
Anemia, Kidney disorders
• Factors that trigger Lupus:
– Infections, Antibiotics, Ultra-violet lights,
Extreme stress, Hormones
AUTOIMMUNE DISEASES
Infectious v. Noninfectious
diseases
• Infectious disease - Any disease
caused by the presence of pathogens
in the body
–Easily spread from one person to
another or from one body part to
another
• Non-Infectious disease - One that
does not spread
–Rheumatoid arthritis
Prevention & Control
• Vaccine – a preparation of weakend or killed
pathogens. It can prompt the body to produce
immunity to the disease.
• Immunity – the body’s natural way of killing
pathogens.
• Antibodies – compounds that block the growth &
reproduction of bacteria.
– When a bacterial infection occurs, antibiotics can be
used to fight the disease.
– Animals can suffer from bacterial diseases as well.
Ex. Anthrax – sheep to farmers & wool workers which
can lead to death. (biological warfare)
Active v. Passive immunity
• Immunity – resistance to a particular
disease
• Active immunity - immunity that you
get because you have been exposed
to a disease
• Passive immunity – immunity that
you get because of a vaccine
T cells and B cells
• Both are white blood cells
• Regulated by helper T cells
• B cell response – defense that aids the removal
of extracellular pathogens
– B cells
• Stay in lymph nodes & organs
• Mature in bone marrow
• T cell response – destruction of intracellular
pathogen by cytotoxic T cells
• Both lymph, organs & circulation
• Occur in thymus gland (located in lower
neck & thorax)
• Act directly against certain pathogens
Specific v. Nonspecific
• Nonspecific – always present, fights
off anything foreign to the body.
–2 lines of defense (1 outside, 1
inside)
• Specific – body has been exposed to
disease before (immunity to chicken
pox once you have already had the
disease)
• 1st line of nonspecific defense
– Mucous membranes – traps it before it
can enter the body
– Skin – acts as a physical barrier
– Sweat – contains lysozyme (which
digest bacterial walls)
• 2nd line of nonspecific defense
– Inflammatory response
– Temperature response
– Proteins
– White blood cells
• Temperature response
–Disease causing bacteria don’t grow
well at high temperatures
–Normal body temperature 37º C
(98.6º F)
–> 39º C (103º F) – dangerous
–>41º C (105º F) - fatal
• Inflammatory
response
• Protein complement system
– About 20 different proteins circulate in the
blood and became active when they
encounter certain pathogens by attaching to
the surface of proteins and damaging
plasma membrane.
• Interferons
– Protein is released by cells infected with
virus which causes nearby cells to produce
an enzyme that prevents viruses
White blood cells – patrol the bloodstreamwait to attack the pathogen
– Neutrophils – engulf bacteria, then release
chemicals that kill bacteria, can also squeeze
between cells in the walls of capillaries to
attack pathogens.
– Macrophage – ingest & kill bacteria and
clear dead cells & other debris, travel
through the body in lymphatic systems and &
between cells, concentrated in particular
organ (spleen and lungs)
– Natural killer cells – attack cells infected
with pathogens, puncture cell membrane,
water rushes into infected cell which swells &
burst (body’s defense against cancer)
•
•
•
•
•
SPECIFIC RESPONSE
White Blood Cells – produced in bone
marrow and circulate in the blood and lymph
nodes
Macrophage – consume pathogens and
infected cells
Cytotoxic (killer) T cells – attack & kill
infected cells
B cells – label invaders for later destruction by
macrophages
Helper T cells – activate cytotoxic T cells & B
cells
• Infected cell has an antigen
(substance that triggers an immune
response) of an invader on its surface
• White blood cells are covered with
receptor proteins that respond to
infection by binding to specific
antigens on the surfaces of the
infecting microbes
• They recognize and bind to antigens
that match their particular shape.
Viral diseases
usually cannot be cured,
but many can be prevented
by
•Good hygiene
•Immunization
Bacteria share DNA when they swap
plasmid rings through a process
called__________________.
A.
B.
C.
D.
Conflagration
Conjugation
Condescension
Condensation
Warm-Up!!! 3/29
Bacteria reproduce ____________ through
a process called ________ ________.
A.
B.
C.
D.
Sexually; biotic fission
Asexually; binary fission
Sexually; binary fission
Asexually; biotic fission
Warm-Up!!! 3/29
Bacteria reproduce ____________ through
a process called ________ ________.
A.
B.
C.
D.
Sexually; biotic fission
Asexually; binary fission
Sexually; binary fission
Asexually; biotic fission
Warm-Up!!! 3/29
Bacteria share DNA when they swap
plasmid rings through a process
called__________________.
A.
B.
C.
D.
Conflagration
Conjugation
Condescension
Condensation
Warm-Up!!! 3/29
Bacteria share DNA when they swap
plasmid rings through a process
called__________________.
A.
B.
C.
D.
Conflagration
Conjugation
Condescension
Condensation
Warm-Up!!! 3/29
Bacteria share DNA when they swap
plasmid rings through a process
called__________________.
A.
B.
C.
D.
Conflagration
Conjugation
Condescension
Condensation