PART I Chapter 18

Archaebacteria & Eubacteria

Chapter 18. 1 Learning Targets:Prokaryotes are diverse organisms that

live in nearly all environments.

Differentiate among archaea and bacteria and

their subcategories.

Describe survival mechanisms of bacteria at both the individual and population levels.

Describe ways that bacteria are beneficial to humans.

Archaea

http://www.youtube.com/watch?v=W25nI9kpxtU

7:16 min

Phylogeny

Characteristics• First living evidence on earth • Unicellular• Prokaryotes (No membrane-bound organelles)• Cell wall with internal plasma membrane• Found everywhere

Bacteria

Bacteria Structures• Cell wall – provides support and protection to

the cell

• Plasma membrane – flexible, selectively permeable boundary that controls what enters and leaves the cell

• Cytoplasm – semi-fluid material inside the cell’s plasma membrane

• Ribosome – organelle that helps to manufacture proteins

• DNA - stores and communicates genetic information for the cell

Bacteria Structures

• Pilus/pili - hairlike protrusion– to stick to surfaces– a bridge for sexual reproduction

• Flagellum - long, whiplike protrusion, for moving

• Capsule - sticky layers around cell wall

• Toxin - a powerful poison

• Endospore – found in some bacteria - resists harsh environments

Flagella

Capsules

Endospores Survival of Bacteria

Endospores

Classification:Three Basic Shapes

Cocci -Spheres

Bacilli -Rods

Spirilli -Spiral

Classification:

• Gram stain – Cell wall type

• Thick – Purple Stain = “Gram Positive”

• Thin - Pink Stain = “Gram Negative”

Growth Patterns

Diplo- pairsStaphylo- clusters Strepto- chains

Pneumonia

Streptococci

Archaebacteria – ancient bacteria

Methanogens

Live in:Oxygen-free environment

Produce methane gas

Halophiles

Live in:Salt water

Acidophiles:

Live in:Hot, acidic

water

Bacteria

http://www.youtube.com/watch?v=h-z9-9OOWC4

11:04 min.

Eubacteria - “True” bacteria

Heterotrophs

Photosynthetic

Autotrophs

Chemosynthetic

Autotrophs

Saprophytes (decomposers)

Need sunlight to make food

Need sulfur & nitrogen to make food

Parasites (cause disease)

Example: Cyanobacteria

Nitrogen fixation

(FIX the nitrogen)

Live in more habitable environments

Cyanobacteria - “blue-green bacteria”Algae + Bacteria

Beneficial Bacteria• Nitrogen fixation

– Converts nitrogen into ammonia

– a form that plants can use

• Nodules – A symbiotic relationship

between bacteria and plants

(Beneficial Bacteria)

Saprophytes (decomposers) – Breaks down dead organisms and

decaying matter– Returns nutrients to soil

(Beneficial Bacteria)

Make food:– Cheese– Pickles– Yogurt– Vinegar– Sauerkraut

Cellular Respiration

Obligate Aerobes

Obligate Anaerobes

Need Oxygen Die from Oxygen

Pathogenic Bacteria – disease-causing bacteria

• Pathogen – an organism that causes disease

• Produce toxins

• Damage host’s tissues

• Enter through openings in body (via air, food, water)

Antibiotics:~ Destroys cell wall of bacteria~ Creates holes in the cell walls

Sir Alexander Fleming1928 - discovered Penicillium notatum

Air-Born

Air-Born Bacteria

Sulfur Bacteria

Reproduction

Asexual• Binary Fission

– Cell division

• Rapid - 20 min.

Sexual• Conjugation –

exchange genetic material

• Pili/pilus - bridge

Binary Fission: Asexual Reproduction

Conjugation - Sexual Reproduction

PART IIChapter 18

Ecology

10 Leading Causes of Death in South Dakota (1991 – 2011)

• Heart Disease 2,324

• Cancer 1,524

• Stroke 466

• Chronic Lower Respiratory 324

• Influenza/Pneumonia 310

• Accidents 305

• Diabetes 137

• Suicide 99

• Aortic Aneurysm 74

• Kidney Disease 69

• All other 1,004

South Dakota 2011 Deaths. 7,271 total

• Cancer 1,656

• Heart Disease 1,615

• Chronic Lower Respiratory 485

• Stroke 442

• Alzheimer’s 423

• Accidents 407

• Diabetes 267

• Influenza/Pneumonia 178

• Suicide 125

• Dementia 117

• All other 1,556

Old & Odd: Archaea, Bacteria & Protists - CrashCourse

Biology #35

http://www.youtube.com/watch?v=vAR47-g6tlA