Take 5 1/26/12 Biologists use ___________ to create a cladogram. Prokaryotes that live in moist habitats that can live almost everywhere are ____________. How does penicillin kill bacteria? Derived traits Eubacteria It causes holes to develop in the bacteria cell walls, water enters and bursts the bacteria cells.

Take 5: 1/24/12 What is the difference between the lytic cycle and the lysogenic cycle? Which of the 2 cycles will stay with the host for the duration of the host’s life? Is a virus prokryotic or eukaryotic? Lytic = Host cell uses viral DNA to produce new viruses from 1 cell Lysogenic = Viral DNA is inserted into host cell’s DNA making a provirus Lysogenic Neither!!! A virus is not considered a living thing

Take 5: 1/30/12 Endospore The two-name naming system Prokayotes A tiny structure that contains a bacterium’s DNA, and encased by a tougher outer covering that resists extreme temperatures and harsh environments is called a(n) _____________. Carols Linneas is known for ______________. Organisms in Kingdom Archaebacteria and Kingdom Eubacteria are similar in that they all are _______________________ Endospore The two-name naming system Prokayotes

Archaebacteria & Eubacteria

Prokaryotes Unicellular Do not have a nucleus or membrane-bound organelles

Prokaryotes 2 kingdoms Biochemical differences between 2 kingdoms Ex: cell walls and lipids in cell membrane differ Structure of archaebacteria is more similar to eukaryotes than eubacteria

1. Archaebacteria: “extremists” Mainly live in oxygen-free environments Some live in marshes, lake sediment, digestive tract of cows, & sewage disposal plants Another type lives in UT’s Great Salt Lake Another one lives in hot, acidic water of sulfur springs and near hydrothermal vents

oxygen-free environments

2a) Eubacteria: heterotrophs Live almost everywhere Use organic molecules for food Some are parasites Some are saprophytes (feed on dead organisms or organic waste)

2b) Eubacteria: Photosynthetic autotrophs Live with a lot of sunlight, make their food Ex: cyanobacteria Live in ponds, streams, & moist areas of land

2c) Eubacteria: Chemosynthetic autotrophs Make their food Don’t use sunlight Breakdown & release energy form inorganic compounds containing nitrogen and sulfur in a process called “chemosynthesis”

Very small cell It’s Prokaryotic! (write this down) What is a bacterium? Very small cell It’s Prokaryotic! (write this down)

The structure of bacteria Write this down: Cell wall-support Pilus-conjugation (reproduction) Capsule- protection Plasmid-genes Flagellum- movement Sir Alexander Fleming, 1928, discovered penicillin (by mistake!), antibiotic (kills bacteria) interferes with ability to make cell walls. They rupture and die. (This bacteria is often lives in hypotonic environments)-

Identifying bacteria + - Anthrax Gram Staining Technique Depends on composition of cell wall Purple or pink Gram + affected by different antibiotics from Gram – Pink = (-) Know!!!!! Purple = (+) Know!!!!! + - Anthrax

Identifying bacteria 3 common shapes Spheres or round (cocci) Rods (bacilli) Spirals (spirilla) pronounced “Cox – sigh”

Reproduction by binary fission (Asexual Reproduction) Bacteria cannot reproduce via mitosis or meiosis They reproduce asexually via binary fission Bacterium copies its chromosome Chromosomes separate and attach to cell membrane Cell elongates Partition forms and new cell wall/cell membrane form

Genetically identical! Can occur every 20 min Genetically identical!

Sexual reproduction Bacterial sex aka conjugation One bacterium transfers all or part of its chromosome to another cell through a bridge-like structure pilus (plural pili) that connects 2 cells This results in genetic variation! Then they can undergo binary fission to duplicate itself.

Diversity of metabolism in Bacteria (skip) Recall: Breaking down food to release its energy = cellular respiration Obligate aerobes = bacteria that require oxygen for respiration Obligate anaerobes = bacteria that are killed by oxygen Facultative anaerobes = can survive (switch) if conditions change

A bacteria’s second chance Some bacteria produce endospores (when faced with unfavorable environmental conditions) Endospore: tiny structure that contains a bacterium’s DNA and a small amount of its cytoplasm, encased by a tougher outer covering that resists drying out, temperature extremes, and harsh chemicals (resting state) (know!!) When conditions improve, the endospore germinates and begins to grow and reproduce

Endospore

Endospores Can survive 100°C  Use a pressure cooker and sterilize it Canned food must be sterilized and acified If endospores get into improperly sterilized canned food, they grow and produce a toxin, can cause botulism, often fatal disease (Clostridium botulinum) Symptoms: skeletal muscle paralysis that may cause sudden respiratory arrest and death if untreated

Anthrax Bacillus anthracis, lives in soil, causes anthrax, mostly infects cattle and sheep, and can affect humans Bacterial spores = airborne, can germinate in lungs and cause infection Produces toxins in lungs that damages lung tissue and circulatory system

Importance of Bacteria Help fertilize fields Recycle nutrients Produce food and medicines Bacteria break down organic wastes, returning nutrients

Nitrogen fixation Bacteria turns nitrogen gas into ammonia (aka nitrogen fixation) Other bacteria convert ammonia to nitrite and nitrate for plants to use Some live symbiotically within roots of trees and legumes (peas, peanuts, soybean) Help to replenish nitrogen in the soil

Food and medicine Swiss cheese, crispy pickles, tangy yoghurt  thank bacteria! Provide distinct flavors and aromas Make vinegar, cheeses, sauerkraut Bacteria inhabit your intestines and produce vitamins and enzymes to help digest food Some produce antibiotics to destroy other types of bacteria

Bacteria cause disease Causes disease in plants and animals Crop loss and loss of livestock Causes disease in humans Carried in air, food, water, through skin wounds Ex: tuberculosis, pneumonia

Threat of Tuberculosis

The end