Biodiversity - unit 2.1 - unit 2.3

What are general characteristics of prokaryotes

• No nucleus

• No membrane-bound organelles

• Unicellular

• Energy produced using free-floating cytoplasmic enzymes

• Most possess cell walls

• Microscopic

What are the three domains of life

• Eukarya

  • Eukaryotes

    • Membrane-bound organelles

• Bacteria

  • Prokaryotes

    • No nuclei

• Archaea

  • Prokaryotes

    • No nuclei

Explain Archaea in a nutshelll

• domain → archaea

• kingdom →archaebacteria

• Previous considered a type of bacteria

  • Similar to bacteria in size, shape and component

  • Different cell wall structure from bacteria

  • Genetics and biochemistry more similar to eukaryotes

• Thought to be extremophiles

  • Live in extreme conditions

Why was archaea previously considered a type of bacteria? Why is it not anymore?

• Because they are similar in size, shape and component

• Now classified differently because:

  • Different cell wall structure from bacteria

  • Genetics and biochemistry is more similar to Eukarya and eukaryotes than with bacteria

What are extremophiles? What are the types of extremophiles

• Archaeas are thought to be mainly extremophiles

• Means to live in extreme conditions

• Types of extremophiles:

  • Halophiles → live in habitats with high salt

  • Thermophiles → Live in habitats with extreme temperature

  • Alkaliphiles → Live in habitats with high pH

  • Acidophiles → Live in habitats with low pH

What is endosymbiosis?

• When an organism is able to live inside another

• Ex: When an archaea-like cell engulfs a bacterial cell via the process of endosymbiosis

• Early eukaryotes were likely descendants of archaea

Explain bacteria in a nutshell

• Domain →bacteria

• Kingdom → eubacteria

• 10x more bacteria in your body than cells (100 trillion x 10)

• Every square centimetre of your skin contains 1 million bacteria

• Over 25 different types of bacteria in your mouth alone

• Small intestine → area of your body with the most bacteria

What is the germ theory?

• The theory is that a specific microorganism can cause a specific disease in people

What is pathogen?

• disease causing agents

Are bacterias friends or foes?

• Some cause disease, some are very important for us to live

  • Mutualism vs parasitism

What are some examples of bacteria as a probiotic?

• Activia → yogurt

  • Contains the bacteria Bifidobacterium regularis

  • Each Activia yogurt contains 1 000 000 000 B. regularis

  • Help people digest milk products (lactose more easily)

  • Prevents constipation (easier to go to the washroom)

  • Less gas and decreased ‘bloated’ feeling

What are health benefits of the yogurt activia

• Contains the bacteria Bifidobacterium regularis (B. regularis)

  • Helps people digest milk products (lactose) more easily

  • Prevents constipation (easier to go to the washroom)

  • Less gas and decreased ‘bloated’ feeling

What are examples of bacteria in cheeses (in the industry)?

• Brevibacterium linens → Blue cheese

• Streptococcus thermophilus → Mozzarella

What is E. coli O157:H7 ?

• There are many different types (strains) of E. coli. Many are not harmful to us

• E. coli O157:H7 is one of the few strains that is deadly

• the ‘O157:H7‘ in the name tells us what special markers are on the surface of the E. coli

  • Different strains of E. coli will have a different number in their name

What does the ‘O157:H7’ in the name E. coli tell us?

• The ‘O157:H7’ in the name tells us what special markers are on the surface of the E. coli

  • Different strains of E. coli will have a different number in their name

How is E. coli O157:H7 transmitted around?

• E. coli is found in the intestines and feces of many animals (ex: raw milk)

• Major sources for humans → Eating undercooked ground beef

  • When the cow is killed, some of the bacteria from the intestine and feces can mix in with the beef

How are different bacteria named?

• They are named based on the shape and arrangement they take on

• Variety of shapes include:

  • Spherical → cocci

  • Rod-shaped → bacilli

  • Spiral shaped → spirilli

• Variety of arrangements include:

  • Diplo → paired

  • Staphylo → clusters

  • Strepto → chains

What are tools for motility/movement for bacteria

• Flagella → whip-like structures propel bacteria forward

• Corkscrew motion → used by spirilli bacteria

• Glide on mucous secretions

What are the 5 different categories of characteristics of bacteria?

1. Cell shape

2. Motility (method of movement)

3. Nutritional modes of bacteria

4. Reproduction

5. Cell wall structure

What are the different nutritional modes for bacteria?

• Heterotrophs → take up organic molecules from the environment or eating other organisms

• Photoautotrophs → Use sunlight and carbon dioxide to make carbohydrates (photosynthesis)

• Photoheterotrophs → Like heterotrophs, but can also use light energy

• Chemoheterotrophs → Use energy generated through chemical reactions involving ammonia, hydrogen sulphide and other similar chemicals

What are the different ways a bacteria can reproduce?

• Binary fission

  • Asexual reproduction

  • DNA replicates

  • Cell grows in size

  • Cell membrane pinches in middle

  • Two genetically identical daughter cells produced (barring mutations)

  • Little room for evolution

  • Average time span: 20 minutes

• Conjugation

  • ‘sexual’ reproduction

  • Bacterial cells temporarily join via a mating bridge to exchange genetic material

  • Plasmids are exchanged (separates rings of DNA from cell’s main chromosome)

• Transformation

  • Not really a form of reproduction

  • Bacteria take pieces of DNA from the environment

  • Useful technique in research to get bacteria (often a strain of E. coli) to mass-produce desired enzymes or compounds)

What are heterotrophs?

• bacterias that use the nutritional mode of heterotrophs where they take up organic molecules from the environment or eating other organisms

What are photoautotrophs

• bacterias that use the nutritional mode of photoautotrophs is where they use sunlight and carbon dioxide to make carbohydrates (photosynthesis)

What are photoheterotrophs?

• bacterias that use the nutritional mode of photoheterotrophs is where they are kind of like both photoautotrophs and heterotrophs, where they are able to take up organic molecules from the environment or eat other organisms and then also use light energy

What are chemoheterotrophs?

• bacteria that use the nutritional mode of chemoheterotrophs use energy generated through chemical reactions involving ammonia, hydrogen sulphide and other similar chemicals

How do bacteria reproduce using Binary fission?

• Asexual reproduction

• DNA replicates

• Cell grows in size

• Cell membrane pinches in middle

• Two genetically identical daughter cells produced (barring mutations)

• Little room for evolution

• Average time span: 20 minutes

How do bacteria reproduce using conjugation?

• ‘sexual’ reproduction

• Bacterial cells temporarily join via a mating bridge to exchange genetic material

• Plasmids are exchanged (seperate rings of DNA from cell’s main chromosome)

How do bacteria reproduce using transformation

• Not really a form of reproduction

• Bacteria take pieces of DNA from the environment

• Useful technique in research to get bacteria (often a strain of E. coli) to mass-produce desired enzymes or compounds

• Ex: green fluorescent protein (GFP) gene is transformed into bacteria to be mass produced

What are the functions of the cell wall of a bacteria?

• Provides structure and protection

• Maintains shape of cell

• Filters certain substances

• Contains peptidoglycan

  • Major component of the cell wall

  • made of polymers of carbohydrates and amino acids

What are two ways of classifying bacteria according to their cell wall structure?

• Gram positive

  • Thick layer of peptidoglycan

  • Stain dark blue or violet

  • Most pathogenic (dangerous) bacteria are gram positive

• Gram negative

  • Thinner layer of peptidoglycan found between outer and inner membrane

  • Stain pink

  • Pathogenicity associated with molecules found in outer membrane

  • Usually more resistant to antibiotics due to their cell wall structure (protected by cell membrane)

Compare and contrast gram negative and gram positive bacteria

• Gram positive

  • Thick layer of peptidoglycan

  • Stain dark blue or violet

  • Most pathogenic (dangerous) bacteria are gram positive

• Gram negative

  • Thinner layer of peptidoglycan found between outer and inner membrane

  • Stain pink

  • Pathogenicity associated with molecules found in outer membrane

  • Usually more resistant to antibiotics due to their cell wall structure (protected by cell membrane)

What unique components do antibiotics attack of a bacteria?

• Target unique compounds or metabolic processes

• Cell wall - very often the peptidoglycan is attacked

  • Gram negative bacteria usually are more resistant to antibiotics due to their cell wall structure (protected by cell membrane)

Which bacteria are more resistant to antibiotics: gram negative bacteria or gram positive bacteria

• Gram negative are more resistant to antibiotics

  • Protected more by cell membrane

Identify three differences between archaea and bacteria

• Different cell wall structures

• Different genetics and biochemistry

• Archaeas live in more extreme environments

Describe how prokaryotes are able to move through the environment

• Flagella → whip-like structures propel bacteria forward

• Corkscrew motion → used by spirilli bacteria

• Mucous secretions

What are three major types of morphology found in bacteria?

• Named based on variety of shapes:

  • Spherical → cocci

  • Rod-shaped → bacilli

  • Spiral shaped → spirilli

• Named based on arrangement of shapes:

  • Diplo → paired

  • Staphylo → clusters

  • Strepto → chains

Match the following ways bacteria obtain nutrition with the appropriate nutritional classification: heterotroph, chemoautotroph, photoautotrophs, photoheterotroph

a) Bacteria consuming energy from human tissue

b) Bacteria receiving all their energy from sunlight

c) Bacteria using energy from the sun during the day and then consuming other bacteria during the night

d) Bacteria receiving energy from chemical reactions around a deep sea vent

a) Heterotroph

b) Photoautotroph

c) Photoheterotroph

d) Chemoautotroph

Examine the graph below to answer the following questions

a) How many bacteria were produced during the second hour

b) At this rate, how many bacteria would be present at the end of four hours

c) What type of bacterial reproduction that you read about in this chapter would account for this type of rapid growth

d) If one cell became resistant to an antibiotic due to a mutation at the 80-minute Mark, how many cells would be resistant at the end of the 120-minute mark (assume the same growth rate)

a) 640 bacteria

b) 40960 bacteria

c) binary fission

d) 4 resistant bacteria cells

Explain protists in a nutshell

• Domain → Eukarya

• Kingdom → Protista

• Category for the ‘uncategorizable’

  • Any eukaryotic organisms that is not an animal, plant, or fungus is a protist

What are general characteristics of protists?

• Typical eukaryotic cell structure

• Most are unicellular or form colonies

• Some multicellular protists exist (kelp is considered a protist)

Explain the different ways of movement in protists

1. Stream cytoplasm into extensions called pseudopodia

   • Ex: Amoebas creep slowly in a direction using their pseudopodia

2. Use of flagella and cilia (much shorter than flagella and all around cell membrane)

   • Ex: zoogflagellates are heterotrophic protists that have one or two flagella

3. Reliance on water, currents, wind and host animals

   • Ex: Apicomplexa release spores that can grow inside organisms as parasites

How do protists reproduce?

• Protists like amoebas, paramecia and most ciliates reproduce through a process similar to binary fission

• Paramecia can also exchange genetic material with each other through conjugation (though this doesn’t produce offspring)

• Many protists alternate between sexual and asexual reproduction

  • Slime moulds and plasmodium (causes malaria) undergo reproduction as shown

What are the types of protists?

1. Animal-like protists

   • Also known as Protozoa

   • Heterotrophic

   • Four different phyla, based on motility:

     • Amoeboids

     • Flagellates

     • Ciliates

     • Apicomplexa

2. Plant-like protists

   • Also known as Algae

   • Photosynthetic

     • Contain chloroplasts

   • Can be unicellular, form colonies and multicellular

   • Six types:

     • Dinoflagellates (possess flagella and a cell wall made of cellulose)

     • Red algae

     • Brown algae

     • Green algae

     • Diatoms

     • Euglenoids (no cell wall but can undergo photosynthesis)

3. Fungi-like protists

   • Heterotrophic (feed on decaying organic matter)

     • Also referred to as decomposers

   • Unlike fungi, most are unicellular but form colonies

   • Form spores

     • Reproductive cells that enter the bodies of other organisms and live as parasites

   • Two main types:

     • Slime mould (branching protist found on decaying matter)

     • Water mould (decompose dead matter in freshwater habitats)

What are animal-like protists?

• Common name → protozoa

• They are heterotrophic (capture and ingest food

• Four different phyla, based on motility:

  • Amoeboids

  • Flagellates

  • Ciliates

  • Apicomplexa

What are the four different phyla of animal-like protists?

• Four different phyla, based on motility:

  • Amoeboids

  • Flagellates

  • Ciliates

  • Apicomplexa

What are plant-like protists?

• common name → algae

• Photosynthetic (create food using light)

  • Contain chloroplasts

• Can be unicellular, form colonies, and multicellular

• Six types:

  • Dinoflagellates (possess flagella and a cell wall made of cellulose)

  • Red algae

  • Brown algae

  • Green algae

  • Diatoms

  • Euglenoids (no cell wall but can undergo photosynthesis)

What are the six types of plant-like protists?

• Six types:

  • Dinoflagellates (possess flagella and a cell wall made of cellulose)

  • Red algae

  • Brown algae

  • Green algae

  • Diatoms

  • Euglenoids (no cell wall but can undergo photosynthesis)

What are fungi-like protists?

• Common names → Slime mould or water mould

• Heterotrophic (feed on decaying matter)

  • Also referred to as decomposers

• Unlike fungi, most are unicellular but form colonies

• Form spores

  • Reproductive cells that enter the bodies of other organisms and live as parasites

• Two main types:

  • Slime mould → branching protist found on decaying matter

  • Water mould →decompose dead matter in freshwater habitats

What are the two main types of fungi-like protists

• Two main types:

  • Slime mould → branching protist found on decaying matter

  • Water mould →decompose dead matter in freshwater habitats

Explain why an amoeba and paramecium are considered “animal-like” protists

• Because they are heterotrophs and surround prey to digest

Identify the organism that causes malaria and describe its life cycle

• Carried in mosquitos that are infected with Plasmodium

  • A mosquito infected with Plasmodium bites a human

  • Plasmodium infects human liver cells, which eventually burst, releasing a different form of protist

  • Plasmodium infects red blood cells and divide asexually. The red blood cells burst and release more plasmodium cells

  • Another mosquito bites the infected person and picks up plasmodium cells

  • Plasmodium reproduces sexually in the mosquito

What characteristic do all protists have in common?

• They are all eukaryotic

Contrast three models of movement among protists

• Pseudopodice → streaming cytoplasm into extensions that creep and stretch slowly in a certain direction using their pseudopodia

• Flagella and cilia → using their flagella and cilia to move around

• Reliance on water, currents, wind and host animals

Use the photograph to answer the following questions

a) Explain how the organism in the photograph obtains food

b) Based on this organism’s mode of nutrition, what group of protists would you classify it in

a) The photo shows an amoeba

• Amoebas slowly engulfs food with pseudopodia, where they surround their prey/food , forms an internal food vacuole, or cavity, that digests the food

b) Animal-like protist and heterotroph as they capture food and ingest food

The graph indicates the depth that certain wavelengths (Colours) of light penetrate water.

a) Which Colours of light are available for photosynthesis by algae that live at a depth of 10m? 70m?

b) Some algae grow best when both blue, violet, and red light are available for photosynthesis. At what depth range would you expect to find this algae

c) Red algae can grow at depths of 100m or more. What can you infer about the type of red light algae can use for photosynthesis? Explain

a) 10m → violet, blue, green, yellow, orange, and red

• 70m → violet and blue

b) Up to 10m of depth

c) Red algae doesn’t use red light for photosynthesis, but instead reflects it so we see red

What characteristics of Euglena make it challenging to classify?

• Euglena has no cell wall, so that made it challenging to classify, however, undergoes photosynthesis so most biologists classify them with algae (plant-like protists)

Explain fungi in a nutshell

• Domain → Eukarya

• Kingdom → fungi

• More closely related to animals than plants

What are general characteristics of fungi

• Heterotrophic → no photosynthesis

• Decomposers → use powerful enzymes to break down organic matter into nutrients that they absorb

  • Food sources include fallen logs, dead animals, wastes of living things

  • Also important in recycling nutrients like nitrogen and carbon into the soil

• Some fungi live as parasites → absorbs nutrients from cells or body fluids of living hosts, damaging the organism

  • Ex: Blight, corn smut, athlete’s foot

• Fungi cells are eukaryotic

  • Contain cell walls made of chitin (a strong carbohydrate polymer

• Yeasts are a group of unicellular fungi, but most are multicellular

• Most can reproduce both asexually and sexually

What are the primary structures of fungi?

• Hyphae (singular → hypha)

  • Many cells surrounded by a single cell wall to form long fibres

  • Cell walls in hyphae contain structures called cross-walls that divide cells; porous to allow cytoplasm and nutrients to be evenly distributed through the fungus

• Mycelium

  • Underground network of hyphae

• Fruiting body

  • Usually the visible part of the fungus above the ground

  • Reproductive structure

  • Produces spores

• Mycorrhizae

  • Vast networks of mycelia that forms a mutualistic relationship with plant roots

  • Receives sugars, starches, proteins, lipids from plant roots

  • Acts like an extension of plant roots and help the plant collect nutrients like water and phosphorus

  • Small size allows the mycelia to penetrate into spots that plant roots cannot

What are the two ways fungi can reproduce asexually?

• Budding

  • Small piece of hyphae breaks off and becomes a separate organism

• Spores

  • Haploid cells (n) → each spore cell contains a single cet of chromosomes (46)

  • Reproductive cells spread by the wind and can germinate (grow) under favourable conditions

How can fungi reproduce sexually?

• Fungi have two different sexes:

  • +

  • -

• Opposite haploid (n) hyphae grow towards each other and fuse to form a diploid (2n) zygospore

  • Zygosphore has two sets of chromosomes from each parent hyphae

  • Produces haploid spores that are genetically unique

  • Increases genetic diversity; allows for adaptation to changing environment

What are the main phylas of fungi?

• Different phyla of fungi classified primarily based on reproductive structures

  • Chytridiomycota (chytrids)

    • Spores are flagellated and motile

    • Ex: chytrids (parasites on amphibians)

  • Zygomycota (common moulds)

    • Produce zygosphores which are highly resistant to environmental conditions

    • Ex: bread mould

  • Ascomycota (sac fungi)

    • sacs called asci contain spores

    • Sacs found on top of fruiting body

    • Ex: Yeast, truffles, morels

  • Basidiomycota (club fungi)

    • Contain club-shaped cells called basidia that contain spores

    • Basidia found under fruiting body

    • Ex: mushrooms

What characteristics define fungi?

• heterotrophic

• Decomposers

• Some are parasitic

• Eukaryotic

• Most multicellular

• Most produce asexually and sexually

How are yeasts different from other fungi?

• Unlike most fungi, yeasts are unicellular

What features of a mycelium make it an efficient structure to obtain food from absorption?

• Mycelium covers a large surface area, so it absorbs a lot of nutrients

What is the purpose of hyphae?

• Hyphae → long, thread-like fibres that make up fungi

State the function of fungal spores

• Spores → reproductive cells of a fungus that help with reproduction

Create a flowchart that describes the reproductive cycle of a typical fungus, such as bread mould

The diagram shows a cross-section of a fungus

a) What is the name of structure “x”? Describe its function

b)What is the name of structure “y”? Describe its function

c) What information would you need to classify this fungus into its correct group

a) x →fruiting body → reproductive structure and produces spores

b) y→ Mycelium → underground network of hyphae + absorbs food/nutrients underground

c) idk

The picture shows the results of an experiment performed on pea plants. Plant (a) has been grown in a soil mixture rich with mycorrhizae fungi. Plant (b) has been grown without the benefit of mycorrhizae. Explain why there is a difference in the two plant root system

• Mycorrhizae has more hyphae that dig deeper and grab extra nutrients

Name 6/7 unique characteristics of all prokaryotes

• No nucleus

• No membrane bound organelles

• free-floating enzymes

• unicellular

• small/microscopic

• cell walls

• asexual reproduction

What are major differences between the archaea and bacteria kingdoms?

• Archaea live in extreme environments

• Diff cell walls

• Different genetics and biochemistry (archaea closer to eukaryotes)

Any disease-causing agent is known as a ________

• pathogen

Name the types of habitats the different type of Achaea live in:

• Halophile

• Thermophile

• Alkaliphile

• Acidophile

• Halophile → high salt env

• Thermophile → high temp env

• Alkaliphiles → very basic env (high pH)

• Acidophile → very acidic env (low pH)

E. coli O157:H7 is primarily transmitted to humans via consuming __________

• Undercooked beef

Rod-shaped bacteria that arrange themselves in straight chains can be referred to as:

• streptobacilli

• Strepto → arrangement

• Bacilli → cell shape

The three methods of motility for bacteria include:

• Mucous

• Flagella

• Corkscrew motion

Name the description for each bacteria on how they obtain energy:

• Heterotroph

• Photoautotroph

• Photoheterotroph

• Chemoautotroph

• Heterotroph → consume nutrients

• Photoautotroph → energy via light (photosynthesis

• Photoheterotroph → energy via light and consuming nutrients

• Chemoautotroph → derive energy from inorganic chemicals

Bacteria can reproduce asexually using a process called ________

• binary fission

In conjugation, no _________ is produced; there is only an exchange of genetic material between two bacterial cells

• Offspring

The ‘structure’ that is created between two bacterial cells that allows for genetic exchange is called a _______________

• mating bridge

The unique components of bacterial cell walls is called ____________

• Peptidoglycan

Compare the two types of bacterial cell walls:

• Gram positive

• Gram negative

• Gram positive

  • Thick layer of peptidoglycan

  • more pathogenic

  • Stain dark blue/ violet

• Gram negative

  • Thin layer of peptidoglycan

  • Stain pink

  • More resistant to antibiotics

The three methods of motility for protists include:

• pseudopodia

• flagella and cilia

• wind, water, animals

Using these type of protists, give the common names, a unique trait, and an example of a representative organism

• Animal-like protist

• Plant-like protist

• Fungi-like protist

• Animal-like protist

  • Common name → protozoa

  • Unique trait → heterotrophic

  • Ex: amoeba

• Plant-like protist

  • Common name → algae

  • Unique trait → photosynthetic

  • Ex: kelp and algae

• Fungi-like protist

  • Common name →slime moulds

  • Unique trait → decomposers

  • Ex: slime moulds or water moulds

Fungi break down and consume dead organic matter, making them _________

• decomposers

Fungi have a unique component in their cell walls called _________

• chitin

The two methods of asexual reproduction in fungi include:

• Releasing spores

• budding

Draw a simple diagram showing sexual reproduction in fungi

Using the different four phyla of fungi, give its common name, its unique reproductive trait and a representative organism

• Chytridiomycota

• Zygomycota

• Ascomycota

• Basidiomycota

• Chytridiomycota

  • Common name → chytrids

  • Unique reproductive trait → spores are flagellated

  • Ex: chytrids

• Zygomycota

  • Common name → molds

  • Unique reproductive trait → zygosphores

  • ex: bread mold

• Ascomycota

  • Common name → sac fungi

  • Unique reproductive trait → inverted fruiting body (asci)

  • Ex: truffles

• Basidiomycota

  • Common name → club fungi

  • Unique reproductive trait →contain basidia that produces spores

  • ex: mushroom