Starter:

Watch Video How was the virus able to enter the

cell? How are viruses able to reproduce? If you breathe in the flu virus, will

you automatically become sick? What are some other viruses you

know about? Are viruses alive? Can medications be used against

viruses?

3/16/2015

175 176Bacteria Bacteria

Application/Connection/Exit:

Ws

3/16/2015

Practice:

Notes

Starter

• Watch and answer questions:

• http://www.schooltube.com/video/08aae2ef0da979dbbb5a/Flu-Attack-How-A-Virus-Invades-Your-Body

•1 Starter•2. Notes•3. Worksheet

March 16, 2015AGENDA

B. 8 A

B.8A Define taxonomy and recognize the importance of a

standardized taxonomic system to

the scientific community while

reading and writing by completing notes and

a ws

Date Lecture/ Activity/ Lab Page2/12 Ordering Fossils Activity 161-1622/13 Evidence of Fossils 163-1642/17 Test Review 165-1662/19-20 Classification 167-1682/23 Dichotomous Key Notes 169-1702/24 Dichotomous Key Project 171-1723/5 Cladagrams 173-1743/16 Bacteria, Viruses, and Protista 175-176

Table of Contents

Bacteria, Viruses, Prions, and Protists

Bacteria

• Unicellular or Multicellular?• Prokaryotic or Eukaryotic?• Cells Walls?

Bacteria

• Unicellular• Prokaryotes• Cells walls containing peptidoglycan

Bacteria

• Extremely Abundant– Cover nearly every square centimeter of Earth

What are the differences between eubacteria and

archaebacteria?

Eubacteria versus Archaebacteria

• Cell walls of Eubacteria have peptidoglycans while those of Archaebacteria do not.

• DNA sequences of archaebacteria is more similar to that of eukaryotes than to the DNA of eubacteria

• Archaebacteria often live in very extreme environments (hot springs, digestive tracts, Great Salt Lake, etc.)

Bacterial Shapes

• Bacilli: rod shaped

• Cocci: spherical

• Spirilla: spiral, corkscrew

Cell Walls

• Gram positive: stain violet due to thick peptidoglycan walls

• Gram negative: stain pink/red, have much thinner walls inside lipid layer

Metabolism

Heterotrophs:• Chemoheterotrophs: must take in organic

molecules and a supply of carbon

• Photoheterotrophs: are photosynthetic but also need to take in organic molecules for carbon source

Metabolism• Photoautotrophs: use light energy to make

carbon compounds

• Chemoautotrophs: use energy from chemical reactions to make carbon compounds

• Where might each type of bacteria be found?

Binary Fission• When a bacteria

grows so that it has doubled in size, it replicates its DNA and divides in half

• Is this sexual or asexual?

• Identical or different daughter cells?

Conjugation

• Some bacteria are able to exchange genetic information

• A hollow bridge forms between two bacteria and genes move from one cell to the other

• Increases genetic diversity of a population

Conjugation

Spore Formation

• Spores are formed when the bacteria produces a thick internal wall that encloses the DNA and part of the cytoplasm

• Why do you think this would be beneficial for bacteria?

Spore Formation

• Occurs when conditions are unfavorable for growth

• Can remain dormant for years until conditions improve

Spore Formation

What are some benefits of bacteria?

Benefits of Bacteria• Some are producers that undergo

photosynthesis• Some are decomposers that break down

dead matter to recycle the nutrients• Some convert nitrogen gas to a form that

can be used by plants (nitrogen fixation)

What are some dangers of bacteria?

Dangers of Bacteria• Break down cells and tissues for food Example: Tuberculosis (destroys lung

tissue)

• Release toxins (poisons) that travel through the body

Example: Streptococcus releases toxins into the blood stream causes strep throat and scarlet fever

Vaccines

• A vaccine is a preparation of weakened or killed pathogens that are injected into the body

• This stimulates the body to produce immunity to the disease

Vaccines

• Why do you think we don’t vaccinate everyone for all disease we have created vaccines for?

Antibiotics• Antibiotics block the growth and

reproduction of bacteria• Used to treat bacterial infections

Solve the Problem

• What would you do to find out what causes the tobacco leaves to be diseased?

Viruses

• A virus is a core of DNA or RNA surrounded by a protein coat (capsid)

Viruses• They can only reproduce by infecting living

cells• They enter a cell and use its cell

machinery to produce more viruses

Retroviruses

• Contain RNA as genetic information instead of DNA

Would you consider viruses living?

Are Viruses Living?

• Cannot reproduce alone, must have a host cell

• Do not undergo growth or development• Do not obtain or use energy• Evolve

Prions

• Diseases such as Scrapie (in sheep) and Mad Cow Disease are not caused by bacteria or viruses. What could cause them?

Prions

• Contain only protein• Cause disease by forming protein clumps

which then induce normal proteins to become Prions

• The build up eventually damages nerve tissue

Protists

• Domain?• Kingdom?• Prokaryotic or Eukaryotic?

Protists

• Domain: Eukarya• Kingdom: Protists• Eukaryotic

Protists

• Protists are defined by what they are not.

Protists are eukaryotes that are not animals, plants, or fungi.

They were the first eukaryotic organisms on earth.

Types of Protists

• Animal-Like Protists: heterotrophs

• Plant-Like Protists: produce food through photosynthesis

• Fungus-Like Protists: obtain food by external digestion

Animal-Like Protists

• Heterotrophs

cilliate

Sarcodine (amoeba)

sporozoan

zooflagellate

Animal-Like Protists

• Malaria• African Sleeping Sickness

Plant-Like Protists

• Carry out photosynthesis

Fungus-Like Protists

• Grow in damp, nutrient rich environments• Absorb food through cell membranes

Starter:

Watch Video How was the virus able to enter the

cell? How are viruses able to reproduce? If you breathe in the flu virus, will

you automatically become sick? What are some other viruses you

know about? Are viruses alive? Can medications be used against

viruses?

3/16/2015

175 176Bacteria Bacteria

Application/Connection/Exit:

Ws

3/16/2015

Practice:

Notes