BACTERIAThe Prokaryotes:Eubacteria and Achaea

SBI3U BiologyDr. Oz (4:37 min): http://www.youtube.com/watch?v=CljhLb1Ar9U

Toilet germs (1:53 min): http://www.youtube.com/watch?v=v6nGgS6ADoI&feature=related

Cell Phones! (3:01 min): http://www.youtube.com/watch?v=4lmwbBzClAc&feature=related

Learning Objectives: Learning Goals Minds ON Bacteria PowerPoint Micro viewers lab Exit card

Learning GoalsWe are / will be learning to… Analyze the risks and benefits of human intervention (e.g. pesticide

use, fish stocking, tree planting, etc.) Analyze how climate change could impact the diversity of living things

(e.g. Global warming, increase in precipitation) Become familiar with terms such as: species diversity, structural

diversity, bacteria, fungi, binomial nomenclature, morphology Classify, apply, and draw dichotomous keys to identify and classify

organisms according to kingdom Explain concepts of taxonomic rank such as genus, species and taxon Compare/contrast characteristics of prokaryotes, eukaryotes and

viruses Compare/contrast anatomical and physiological characteristics of

organisms representative of each kingdom Explain structural and functional changes of organisms as they have

evolved over time Explain why biodiversity is important for maintaining viable

ecosystems

Minds ON Read from Bill Bryson’s “A Short

History of Nearly Everything”

Yesterday’s RecapDichotomous Keys: A tool used to classify organisms based on structural characteristics (≠ colour, where an organism lives, etc.)

Refresher: a prokaryote = Kingdom Archaebacteria and Eubacteria = all bacteria * Can we think of a mental reminder for this?

Bacteria CellSee Fig. 6 on page 48 in text.

Important Structures: Capsule Cell wall – made of peptidoglycan and

outer membrane Plasma membrane Nucleoid region – condensed DNA

molecule Ribosomes in the cytoplasm Pili (Singular = Pilus) Flagellum

Pilus (pili)

Characteristics of BacteriaProkaryotic Cells:

unicellular (single-celled)

no nuclear membrane or other membranes around organelles

small—less than 2 µm (micrometers)

only 1 circular chromosome (plasmid)

Identifying Prokaryotes

Cell Shape Cell Wall Movement

Bacterium Shapes And Groupings

SHAPES Coccus~ Sphere shaped bacteria Bacillus~ Rod shaped bacteria Spirillium ~ Spiral shaped bacteriaGROUPINGS Mono - one Diplo - two Strepto - in a chain Staphylo - cluster

Bacterium Cell Walls: Gram + and Gram –

http://virtuallab.nmsu.edu/stain.php

Cell Walls cont’d Chemical nature of a cell wall can be determined

by Gram Staining.

By finding out what colour the cell produces when it is gram stained you can figure out the type of carbohydrates in the cell wall.

Why would this be helpful?

Gram + vs. Gram - walls

Movement

Flagellum ~ Tail like structure that whips around to propel the bacterium

Cilia ~ small hair-like projections surrounding the cell that help it to “swim”, moves back and forth in a synchronized movement

Non motile ~ Sticky cilia like structures that keep the bacterium from moving

Flagellaperi = around

Cilia

OTHER TERMS USED TO CLASSIFY BACTERIA

Bacterial Respiration Aerobic

Anaerobic

Obligate Aerobes

Obligate Anaerobes

Facultative Anaerobes

Grows in the presence of oxygen

Grows in the absence of oxygen

Must have oxygen

Must have NO oxygen

Can grow with or without oxygen

Bacteria and Metabolism Autotrophs Heterotrophs Chemotrophs

Autotrophs make their own

energy use solar energy

(or other chemical compounds) to ‘fix’ carbon dioxide

eg. Cyanobacteria uses photosynthesis to make glucose

Example: Cyanobacteria Photosynthet

ic Bluish-

greenish color

Contain membranes that carry out p/s

Example: Cyanobacteria Do not contain

the same type of chloroplasts as plants do

This bluish-greenish algae can be found nearly everywhere on earth.

Can survive in extremely hot and cold environments

Why are Cyanobacteria not in the Plant Kingdom??

• Can exist unicellularly

• Prokaryotic (no nucleus and membrane-bound organelles)

Heterotrophs Obtain energy

from eating other organisms

Eg. E. coli

Chemotrophs

makes own energy from chemicals like sulfur or hydrogen sulfide

Eg. Archaebacteria living in deep sea vents

Other Archaea- Terms Chemotrophs/Methanogens –

convert chemical compounds into methane gas

Halophiles – like salt water (oceans)

Extreme Thermophiles – like warm environments (hot springs)

Psychrophiles – cold-loving organisms (Arctic soil)

Bacterial Reproduction

Binary Fission Conjugation Spore Formation

Cellular organism copies its genetic information then splits into two identical daughter cells.

1) 2) 3)

Conjugation

Sexy time! 1 bacterial cell

passes a copy of a plasmid through a hollow pilus

For example, that contains the information such as a resistance to penicillin

1)

3)

2)

Spore Formation: Endospore

A type of dormant cell (sometimes for years)

Exhibit no signs of life

Highly resistant structure that forms around the chromosome when cell is under some sort of environmental stress such as:

-High temperatures-Irradiation-Strong acids-Disinfectants

Archaebacteria or Archaea

Lack important carbohydrate found in cell walls (Gram -) Different lipids in their cell membrane Different types of ribosomes Very different gene sequences Do not cause disease Can live in extremely harsh environments Do not require oxygen (anaerobic)

Eubacteria

Make up the larger of the two prokaryote kingdoms

Generally are surrounded by a cell wall composed of complex carbohydrates

Gram + and – Can cause disease Live nearly everywhere

MICROVIEWER ACTIVITY

HELPFUL BACTERIA

Why Helpful? HARMFUL BACTERIA

Why Harmful?

• make a chart similar to this one • use the microviewers provided to list examples of

helpful bacteria and for each, why they are helpful• do the same for harmful bacteria• practice naming the type of shape and groupings

This powerpoint was modified by Mrs. S. Kerr, Mrs. S.Y. Chen-Allen and Mrs. N. Brannan from www.worldofteaching.com

Exit CardDraw what you think the following look like (refer to your notes):

Streptobacilli

Staphylococci