Presentation is loading. Please wait.

Presentation is loading. Please wait.

I. Characteristics of Bacteria A) Bacteria are Prokaryotes - they have no true nucleus or membrane bound organelles. Instead, DNA is concentrated into.

Similar presentations


Presentation on theme: "I. Characteristics of Bacteria A) Bacteria are Prokaryotes - they have no true nucleus or membrane bound organelles. Instead, DNA is concentrated into."— Presentation transcript:

1 I. Characteristics of Bacteria A) Bacteria are Prokaryotes - they have no true nucleus or membrane bound organelles. Instead, DNA is concentrated into a nucleoid region.

2

3 B) They are unicellular. C) Most bacteria have a cell wall that helps maintain the cell shape. The cell wall also protects the bacterial cell and prevents it from bursting.

4 D) Some bacteria contain a capsule. This is a gelatinous secretion which provides the cell with additional protection and helps the bacteria adhere to their host.

5 E) Some bacteria contain a flagellum which is like a tail anchored to the cell wall. The flagellum works like a propeller and moves the bacteria through a fluid environment.

6 Quick review What do bacteria have that keeps the cell from bursting? What helps some bacteria stick to their host?

7 Quick review What do bacteria have that keeps the cell from bursting? Cell Wall What helps some bacteria stick to their host? Capsule

8 F) Reproduction: Binary Fission - asexual reproduction (no exchange of genetic material) in which the cell simply divides into two equal parts.

9 *bacterial growth is exponential 2 to 4 to 8 to 16 to _____ to _____ to _____

10 Conjugation – A way that genetic material is transferred from one bacteria to another through a tube.

11 II. Response to Oxygen A) Some bacteria need oxygen: Aerobes B) Some bacteria don’t: Anaerobes In fact, some anaerobes cannot survive in the presence of O 2

12 Quick Review How do bacteria exchange DNA? Do bacteria reproduce sexually or asexually?

13 Quick Review How do bacteria exchange DNA? Through conjugation Do bacteria reproduce sexually or asexually? Asexually (Binary fission!)

14 III. Bacteria Fall Into One of Two Kingdoms A) Archaebacteria - Members of this small kingdom live only in extreme places such as high salt environments and hot acidic water of sulfur springs

15 B) Eubacteria - This is the larger group of “normal bacteria”, there are thousands of bacteria types in this group.

16 Quick review In what kingdom are “normal” bacteria categorized?

17 Quick review In what kingdom are “normal” bacteria categorized? Eubacteria

18 Eubacteria may be: –A) photosynthetic ex. cyanobacteria –B) chemosynthetic- make their own –food using chemicals … or –C) heterotrophic – can’t make their own food Ex. Parasitic bacteria

19 A) Nitrogen Fixation - convert N 2 gas into Ammonia B) Recycling of Nutrients (decomposition) - breakdown dead organic matter and return nutrients to the soil

20 The nodules on soybean roots contain Rhizobium bacteria that convert nitrogen gas into ammonia. Symbiosis: plant gains useable source of nitrogen/ bacteria use sugars supplied by the plant

21 C) Food - vinegar, yogurt, cheese, pickles pepperoni sausage

22 D) Health Probiotics – help to break down food in your intestines

23 Disease Causing Agents A. It is estimated that half of all human disease is caused by bacteria B. Examples of bacterial disease: -tuberculosis -strep throat - syphilis -tetanus

24 Bacteria: A Review Let’s Review what we’ve learned Video While watching the video write down –Three ways in which bacteria are beneficial –Three ways in which bacteria can be harmful


Download ppt "I. Characteristics of Bacteria A) Bacteria are Prokaryotes - they have no true nucleus or membrane bound organelles. Instead, DNA is concentrated into."

Similar presentations


Ads by Google