Bio 180 - (Prokaryotes, Protists, and Fungi)

How are prokaryotes good for you?

• Hygiene Hypothesis: proposes that the stimulation of the immune system by microbes protects from the development of inflammatory diseases.

• Food

• Mutualistic/ Commensals relationships ex.) bacteria living on the roots or leaves of a plant get nutrients from the plant and, in return, produce substances that protect the plant from pathogens.

• Nutrient cycling: Recycling CO2

• Electricity: harness energy from microbes

• Bioremediation: aids in cleaning up environment.

What are endotoxins?

a toxin that is present inside a bacterial cell and is released when the cell disintegrates. (BREAKS APART, then RELEASES TOXIN)

ex.) Salmonella typhi

What are exotoxins?

Secreted by bacteria. (Just RELEASES TOXIN and doesn’t BREAK APART)

ex.) Vibrio cholera, H. Pylori, Streptococcus B

Who is Robert Koch?

Conducted studies on illnesses caused by microorganisms. Found out that microorganisms may be a leading cause of an illnesses within a person. Confirmed the Germ Theory.

What are the 3 domains of prokaryotes?

Bacteria, Archaea, and Eukarya.

General features of prokaryotes?

• basic and small

• no nucleus

• no membrane bound organelles

Microbiome

Human microbiome (found on/ within humans). If you possess an unhealth microbe on your body, you will become more susceptible to things within the environment. Ex.) asthma

Who is Alexander Fleming?

Creator of penicillin and revolutionized medicine with his discovery of using “bacteria” within medicine.

Common shapes found in bacteria

• Coccus: circle

• bacillus: Rod

• spirillum: Spiral

• vibrio: curved rod (check mark)

External autonomy on prokaryotes

• Capsule: stick, defend, Biofilm

• Pili: Conjunction

• Fimbriae: Stick, numerous

• Flagella: helps in movement, motor, injects toxins

• Cell Wall Plasma membrane

• Gram Staining: (+): Purple and think and (-): Pink and thin

Internal autonomy in prokaryotes

• Nucleoid: main genetic material found in this region

• Plasmids: additional genetic material

• Cytoplasm ribosomes: build cytoplasm proteins

Metabolism in prokaryotes

• Photoautotroph: cells that capture light energy, and use carbon dioxide as their carbon source.

• Chemoautotroph: sulfur-oxidizing bacteria, nitrogen-fixing bacteria and iron-oxidizing bacteria, found in oceans.

• Photoheterotroph: organisms that capture light energy to convert to chemical energy in the cells

• Chemoheterotroph: down organic wastes and the remains of dead organisms. They play vital roles as decomposers and help recycle carbon and nitrogen.

• Aerobic v. anaerobic: (Aero)—> with O2, (anae): without O2

Binary Fission

copying the chromosome and separating one cell into two; making a copy of oneself.

Mutation

Change in genetic code.

Transformation

the prokaryote takes in DNA found in its environment that is shed by other prokaryotes; bacteria get genetic material from environment.

Transduction (virus)

the process by which a virus transfers genetic material from one bacterium to another.

Conjugation (sex pili)

bacteria share the same genetic material as other bacteria.

Horizontal Gene Transfer

the movement of genetic information across normal mating barriers, between more or less distantly related organisms; getting genes from other areas (not just parent cells)

Extremophiles

an organism/bacterium that is able to live in extreme environments.

Halophile/Halobacterium

an organism, especially a microorganism, that grows in or can tolerate saline conditions. Lives in high salt concentrations.

How are prokaryotes different from Eukaryotes?

• No Nucleus

• No membrane bound organelles.

• Different cytoskeleton

• Circular DNA

Miasma Theory

The old and inaccurate belief that the air held sickness ; you could get sick by inhaling “bad air”

Germ Theory

Microbes can in fact cause sickness and disease - and can spread from person to person. Specific microbe for each illness.

What is an endospore?

An endospore is a dormant, tough, and non-reproductive structure produced by some bacteria. It maintains genetic information and half metabolism until it’s in a proper environment, then it releases spores.

Biofilm

sticky most outer layer built within proteins. Used for defense and helps in moisture.

Fimbriae

long filamentous hair-like protein structures located at the surface of bacterial cells. Help attach to other bacteria.

Flagella

a slender threadlike structure, especially a microscopic appendage that enables many bacteria to swim and move. Microtubes are used within the flagella. The flagella has 3 parts.

3 parts of the flagella

• Motor

• Hook

• Tail

who is Hans Christian Gram?

discovers staining bacteria. Depending on how thick or thin the layer is, the cell will be dyed purple (+, thick) or pink (-, thin).

Endosymbiotic Theory

Lynn marriese founded the theory. The theory suggests that ancient bacteria evolved into the bacteria of today.

Reasons backing the Endosymbiotic Theory

• Ancient DNA in mitochondria and chloroplasts are similar.

• The membrane is similar to the ancient protist.

What is a protist?

The first eukaryotes, they are very diverse.

Reproduction in Protists

Asexual reproduction and binary fission

Relationships w/other organisms

• (mutualistic) coral need dinoflagellate to survive (Primary Producers) in photosynthesis carbon sinks and protist absorb carbon.

• (Algae blooms) kill fish.

• (Disease) Protists may cause disease.

Excavata

modified mitochondria, feeding groove, cytoskeleton

• Diplomonads: Giardia (causes stomach pain)

• Parabasalids: Trichorrias (causes vaginalis)

• Euglenozoa: Trypanosoma (african sleeping disease)

SAR- Stramenopiles

straw like structures

• Diatoms: sillica

• Golden Algae

• Brown Algae: Blade, stipe, holdfast

SAR - Alveolates

tiny sac under membrane

• Ciliophora: Paramecium

• Dinoflagellates: Zoomanthellae

• Apicomplexans: Malaria

SAR - Rhizarians

hard outershells photosynthetic and moves with amoeboid projection.

• Radiolarians

• Forams/Formaniferans

• Cercozoans

Archaeplastida

• Red algae

• green algae

How old are fungi?

1.3 trillion

Hyphae

Underground roots of network. 2 types of hyphae :septate hyphae and coenocytic hyphae.

septate hyphae

have walls between cells that allow for the passing of nutrients.

coenocytic hyphae

no walls or membrane between cells

Mycelium

mass network of hyphae

Cells walls in fungi

made of chitin

Mycorhizzae

symbiotic relationship with the roots of plants. The fungi share water with the plants and the fungi in return get the products from photosynthesis.