DomainThere are 3 domains: Bacteria,

Archaea, and Eukarya.

Plants, animals, fungus, and protists

are included in the domain Eukarya.

They are all eukaryotes.

Bacteria and Archaea contain

prokaryotes.

6 Kingdoms The 3 domains are split into 6 kingdoms:

Animalia (animals)

Plantae (plants)

Protista (protists)

Fungi (fungus)

Eubacteria (bacteria without peptidoglycan)

Archaebacteria (bacteria with peptidoglycan –

generally live in harsh environments)

The kingdoms Animalia, Plantae,

Fungi, and Protista are made up of

organisms with eukaryotic cells

The kingdoms Eubacteria and

Archaebacteria are made up of

organisms with prokaryotic cells

Prokaryote Structure

Bacteria and Viruses

Prokaryotes are

microscopic,

unicellular

organisms.

They have some characteristics of all cells,

such as DNA and ribosomes.

Lack a nuclear membrane and other

membrane-bound organelles

18.1 Bacteria

Chapter 18

Photosynthetic

eubacteria

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EubacteriaArchaebacteria

magnification

unavailable

Bacteria and Viruses

18.1 Bacteria

Chapter 18

Eubacteria

Bacteria and Viruses

Very strong cell walls

Contain peptidoglycan (a chain of sugars and

amino acids that forms the cell wall)

Some have a second cell wall

18.1 Bacteria

Chapter 18

Differences Between Eubacteria and

Archaebacteria

Bacteria and Viruses

The cell walls of the eubacteria contain

peptidoglycan, but the cell walls of

archaebacteria do not.

The two groups of organisms have different

lipids in their cell membranes.

Different ribosomal proteins and RNA

18.1 Bacteria

Chapter 18

Gram Stain

Scientists have come up with a test that stains

bacteria different colors based on whether they

have peptidoglycan or not.

If bacteria has peptidoglycan in the cell wall it will

be stained purple. If it does not have

peptidoglycan it will be stained pink.

Is this Eubacteria or Archaebacteria?

Is this Eubacteria or Archaebacteria?

Types of Archaebacteria

Bacteria and Viruses

Archaeabacteria generally live in very harsh

conditions.

Thermoacidophiles (thur muh uh SIH duh filz)

live in hot, acidic environments.

Halophiles (HA luh filz) live in very salty

environments.

Methanogens (meh THAHN oh jenz) cannot

live in the presence of oxygen and create

methane.

18.1 Bacteria

Chapter 18

Photoautotrophs

Bacteria and Viruses

Carry out photosynthesis in a similar manner

as plants

Chemoautotrophs

Break down and release inorganic compounds

that contain nitrogen or sulfur

Aerobes and Anaerobes

Obligate aerobes are bacteria that require oxygen

to grow.

Anaerobic bacteria do not use oxygen for growth

or metabolism.

Ways that Bacteria Get Energy

Chapter 18

3 Shapes of Bacteria

Bacteria and Viruses

Shapes of Bacteria

Spherical = Cocci

Rod-shaped = Bacilli

Spiral-shaped = Spirilla

SpirillaCocci Bacilli

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18.1 Bacteria

Chapter 18

Prefixes

Diplo – cells arranged in pairs

Staphylo – cells arranged in clusters

Strepto – cells arranged in a chain

Bacteria Growth and Reproduction

What type of reproduction do

bacteria do?

What are the advantages?

What are the disadvantages?

Reproduction of Prokaryotes

Bacteria and Viruses

Binary Fission

Division of a cell into two

genetically identical cells

Conjugation

Two prokaryotes attach to each other and

exchange genetic information.

18.1 Bacteria

Chapter 18

Mutations

Bacteria and Viruses

Bacteria reproduce quickly and their population

grows rapidly.

Mutations lead to new forms of genes, new

gene combinations, new characteristics, and

genetic diversity.

This genetic diversity allows bacteria to evolve

over time.

18.1 Bacteria

Chapter 18

Ecology of Bacteria

Bacteria and Viruses

Nutrient cycling and nitrogen fixation

Bacteria are decomposers that return vital

nutrients to the environment.

Nitrogen in the air cannot be used by

plants. Nitrogen-fixing bacteria live in a

symbiotic relationship in the root nodules of

plants such as soybeans, clover, and

alfalfa. These bacteria turn the nitrogen into

a useable form.

18.1 Bacteria

Chapter 18

Nitrogen Fixation Video

http://studyjams.scholastic.com/studyjams/

jams/science/ecosystems/nitrogen-

cycle.htm

Normal Flora

Bacteria and Viruses

Most of the bacteria that live in or on you are

harmless and are called normal flora.

E. coli

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18.1 Bacteria

Chapter 18

Foods and Medicines

Bacteria and Viruses

Some foods/medicines are made with the aid

of bacteria.

cheese

yogurt

buttermilk

pickles

vitamins

insulin

18.1 Bacteria

Chapter 18

Disease-causing Bacteria

Bacteria and Viruses

A small percentage of bacteria cause disease.

Bacteria multiply quickly at the site of infection.

Bacteria secrete a toxin.

18.1 Bacteria

Chapter 18

Viruses

Viruses are not considered to be

alive. What is required for something

to be considered living? (There are 8

characteristics).

The Eight Characteristics of Life

1. Made of one or more cells

2. Displays growth and develops

3. Have a genetic code

4. Reproduces

The Study of Life

1.1 Introduction to Biology

Chapter 1

The Eight Characteristics of Life

5. Responds to stimuli

6. Requires energy

7. Maintains homeostasis

8. Adaptations / evolve over time

The Study of Life

1.1 Introduction to Biology

Chapter 1

Virus Videos

As you watch the videos, consider why viruses are

not alive. Which requirements for life do they not

meet?

https://www.youtube.com/watch?v=PHp6iYDi9

ko

https://www.youtube.com/watch?v=7KXHwhT

ghWI

18.2 Viruses

Viruses

Bacteria and Viruses

A nonliving strand of genetic material within

a protein coat

No organelles to take in nutrients or use energy

Cannot make proteins

Cannot move on their own

Cannot replicate on their own

Most viruses range in size from 5 to 300

nanometers.

Chapter 18

Virus Reproduction

Lytic vs Lysogenic Cycle

In the lytic cycle, viruses insert their

DNA into another cell which then gets

replicated to create more viruses.

The lysogenic cycle is similar, but the

viral DNA is dormant in the host DNA

until it is triggered to make more

viruses.