Your Body’s Abundant Bacteria
Use the box on p. 39 of the article “Are Antibiotics Killing Us?” to answer the questions below.
1. List 5 things in which bacteria play a role in maintaining the health of the human body?
They populate areas of the body, preventing harmful bacteria from taking hold
They help digest food
They help make vitamins
They may help regulate appetite
They may help regulate weight
They help blood vessels of the bowel to develop correctly
They metabolize bile acids
They help regulate pH
2. What is found in tears?
Natural antibiotics
3. What role does Streptococcus play in the eye and Staphylococcus, Neisseria, and Corynebacterium play in the nose?
They thrive in those areas, making it harder for harmful bacteria to cause damage.
4. How many species of bacteria are in the human mouth?
About 500
5. What is the scientific name of the bacteria that secretes plaque?
Actinomyces viscosus
6. What does S. mutans cause?
Bad breath and cavities.
7. What defenses does the skin provide the body against colonization by bacteria?
Low moisture, low pH and high salinity (salt concentration)
8. Why do armpits smell?
3-methyl-2-hexenoic acid, which is secreted by Corynebacterium sp.
9. What bacterium is known to survive the acid of the stomach?
Heliobacter pylori, which causes ulcers
10. What disease is now known to be caused by bacteria in the stomach that used to be attributed to stress?
Ulcers
11. What keeps the small intestines sparsely populated?
Bile and antimicrobial mucus
12. What role does B. theta play in development?
It sends chemical signals needed for blood vessels of the bowels to develop properly
13. Why are the bacteria in the colon anaerobic?
There is no oxygen in the colon
14. What important roles in homeostasis do bacteria play in the colon (3)?
They metabolize bile acids (pH homeostasis)
They break down indigestible parts of our food
They produce vitamins
15. How can obesity in some people be attributed to a bacterial infection?
Some have been shown to disrupt an appetite-suppressing hormone
16. What type of bacteria is known to cause UTIs (urinary tract infections) when introduced to the normally sterile urethra?
E. coli
17. Lactobacillus is a bacteria found in many organisms. It is one of the nonpathogenic bacteria that survive pasteurization and can cause milk to spoil. It appears second in the ecological succession of milk spoilage because as the bacteria present ferment the milk, acids are produced. Only the Lactobacillus can survive the pH of about 4 resulting from these conditions. In the human reproductive tract, this ability to produce acids and survive in acidic conditions becomes important in preventing what type of infection?
Yeast infections (caused by the Candida fungus)
18. What makes feet smelly?
Fermented acids produced by moisture-loving bacteria
19. Identify 6 areas of the body that should remain sterile.
The liver
The gall bladder
The brain
The thymus
The bloodstream
The lower lungs
The urethra
20. How do you feel about the prevalence of antibacterial agents in our everyday world? (soaps, hand-sanitizers, lotion, ointments, and mouth/eye washes, as well as prescriptions). Write a well-thought-out persuasive essay that includes what you have learned in this unit as well as from this article. Take a position either for or against the continued use of antibacterial agents in our everyday world.
Answers will vary
Bacteria WS KEY
Complete the chart below using p. 447:
Important Bacterial Diseases
Disease Description of Illness Bacterium Transmission/Cause
Anthrax / Fever, severe difficulty breathing /Bacillus anthracis
/ Inhalation of sporesBubonic plague / Fever, bleeding, buboes, often fatal / Yersinia pestis / Bite of infected flea
Cholera / Severe diarrhea, vomiting, fatal if not treated / Vibrio cholerae / Drinking contaminated water
Dental cavities / Destruction of minerals in teeth / Streptococcus mutans / Dense collections of bacteria in mouth
Lyme disease / Rash, pain, swelling in joints / Borrelia burgdorferi / Bite of infected tick
Tuberculosis / Fever, difficulty breathing / Mycobacterium / Inhalation
Typhus / Headache, high fever / Rickettsia / Bite of infected flea or tick
What is the name of the bacteria that causes acne? __Propionibacterium acnes_ How do pimples form? Increased oil amounts increase normal bacteria populations
Identify the type of food poisoning, how you get it and the symptoms caused by each of the following bacteria – p. 448
· Staphylococcus aureus – most common; toxins from bacteria in food; nausea, vomiting, diarrhea
· Clostridium botulinum – food not canned properly, not heated enough; deadly toxin affects nervous system, double vision, paralysis, can’t breathe
· Escherichia coli O157:H7 – normal E.coli acquires DNA that codes for a toxin, raw/uncooked ground beef; food poisoning
Explain several ways in which you can prevent getting bacterial infections (p. 448).
Boiling water, chemicals, hot soapy water, antibacterial products
Define biowarfare –deliberate exposure of people to biological toxins or pathogens such as bacteria or viruses
Antibiotics – Read and answer the following questions using p. 449:
1. Who is credited with discovering the first antibiotic? Fleming
2. What kingdom does the organism that produced the antibiotic belong to? Fungi
3. Identify the following organisms in the context of this discovery:
Penicillium – fungus used for penicillin (antibiotic medicine)
S. aureus – bacteria that weren’t growing near the Penicillium
4. Why aren’t antibiotics effective against viruses? B/c they don’t have cellular processes that antibiotics interfere with
5. How do bacteria become resistant to antibiotics? Be specific. Mutations passed on through surviving bacteria
6. Why is it important to take an antibiotic exactly as it is prescribed by your doctor for as long as it is prescribed? To kill all bacteria so there is no chance for a resistant strain to develop
7. What is the term used to describe bacteria that are not affected by several antibiotics? Multiple-antibiotic resistance
8. What do scientists and medical professionals fear will result as a result of the common use of antibacterial soaps and other antibacterial products? May favor resistant bacteria
Importance of Bacteria – Read and answer the following questions using p. 450:
1. Name several foods that are produced using bacteria. Pickles, cheese, buttermilk, olives, vinegar, sourdough bred, some sausage
2. What is used to produce acetone and butanol on an industrial scale? Clostridium
3. What are genetic engineers using bacteria for? Drugs for medicine and complex chemicals for research
4. How do mining companies use bacteria to harvest copper and uranium and what type of bacteria do they use? Chemoautotrophic bacteria that leave behind minerals
5. How do bacteria help in environmental disasters? They metabolize chemicals like petroleum and chemical spills
Instructions: Define the following terms in the boxes with the drawings for each: cocci, bacilli, spirilla, staphylo, strepto, diplo (use p. 443 to help) / Define & draw a cocciRound bacterium
Define & draw a bacilli
Rod shaped bacterium / Define & draw a spirilla
Spiral shaped bacterium
Define & draw a staphylococciCluster of round shaped bacteria
/ Define & draw a staphylobacilliCluster of rod shaped bacteria
Define & draw a streptococciChain (3 or more) of round bacteria
/ Define & draw a streptobacilliChain (3 or more) of rod bacteria
Define & draw a diplococcitwo round bacteria / Define & draw a diplobacilli
Two rod bacteria
KEY
Bacterial Structure & Function
In the space below, draw and label & color the E. coli bacterium shown on p. 446.
1. Is this cell prokaryotic or eukaryotic? ______How do you know? ______
Describe the function or significance of each structure listed below.
2. flagella – single stranded structure used for locomotion; corkscrew movement
3. ribosomes – different than eukaryotic ribosomes, but still the site of translation
4. nucleoid region – area most likely to have the genome
5. genome – all of the genetic material of an organism
6. cell wall – provides shape and support for cell; contains peptidoglycan in the Eubacteria
7. cell (plasma) membrane – surrounds the cytoplasm; functions in homeostasis
8. capsule – found outside the cell wall in some bacteria; can help cell “hide” from host immune system OR can be toxic to host
9. pili – short, thick, rigid structures used for attachment and conjugation
10. cytoplasm – the contents of the cell interior to the plasma membrane except the nucleic acid
11. List the structures that are common to both prokaryotic and eukaryotic cells below.
Ribosomes, nucleic acid, plasma membrane, cytoplasm/cytoskeleton; flagella are not homologous, cell walls are not present in all cells and have different compositions
12. A common word for bacteria that used to be the name of the only prokaryotic kingdom in the 5-kingdom system of classification is monera.
13. How is a bacteria’s DNA different from your DNA? It is in a circle instead of linear; there is less bacterial DNA; there are not histones (proteins) associated with the DNA in bacteria
Matching
B 14. binary fission
E 15. conjugation
D 16. endospore
C 17. transformation
oops 18. transformation
F 19. pili
A 20. plasmid
A. small pieces of circular DNA outside of the main genome that typically carry genes for specialized functions such as antibiotic resistance
B. chromosome replication, followed by cell division; asexual reproduction
C. picking up and incorporation DNA from other bacterial cells
D. special, dehydrated cell formed when conditions are unfavorable
E. exchange of genetic material through cell-to-cell contact; sexual reproduction
F. hairlike structures on the surface of bacteria for adherence and conjugation
21. Many bacteria are helpful to their hosts or to the ecosystem. Describe some roles that bacteria play that are helpful. Bacteria are helpful to the ecosystem in that they produce oxygen, are principle decomposers, and are key to the nitrogen cycle. Bacteria are helpful to hosts in that they help fend off other microorganisims that may be pathogenic, and they help with metabolism (digestion of cellulose, production of vitamin K).
Other bacteria cause disease (pathogenic). Below are some descriptions of various bacterial diseases, followed by fictitious patients and their case histories. Match the patient to the correct diagnosis by writing the name of the disease in the blank that best matches the symptoms given.
· Botulism – very dangerous form of food poisoning; Clostridium botulinum; symptoms include headache, weakness, constipation, and nerve paralysis; may cause death if respiratory organs are paralyzed
· Cholera – common in areas where sanitation is very poor; acute and infectious; Vibrio cholerae; symptoms include severe diarrhea and vomiting, extreme dehydration, muscle cramps, and prostration
· Diphtheria – a highly contagious childhood disease; Corynebacterium diphtheriae; symptoms include sore throat, fever, headache, and nausea; a yellowish membrane forms in the throat that restricts breathing
· Gonorrhea – a sexually transmitted disease (STD); Neisseria gonorrhoeae ; attacks the reproductive system; symptoms do not appear immediately and include painful urination, pus discharged from the penis or vagina; if untreated, may result in sterility
· Lobar pneumonia – inflammation of the lung; leading cause of death in infants and elderly; Streptococcus pneumoniae; solidified lung tissue prevents air from entering alveoli
· Scarlet fever – contagious childhood disease; Group A beta-hemolytic streptococci; symptoms include sore throat, swelling of lymph nodes in neck, bright red rash, nausea, hot dry skin, and fever
· Tetanus – fatal unless treated; Clostridium tetani; symptoms include lockjaw, muscle spasms, convulsions, stiffness, restlessness, headache, and chills; bacterial organisms enter body through a puncture wound
· Typhoid fever – transmitted by contaminated water and food; Salmonella typhosa; symptoms include sore throat, high fever, loss of appetite, diarrhea and constipation, and periods of sweating and chills
· Whooping cough – infectious disease common in children under 10; Bordetella pertussis; symptoms include chills, vomiting, and bluish skin because extreme coughing prevents air from entering the alveoli
22. Lobar pneumonia _ Patient A: 82 years old; has generally poor health; has sharp chest pains, blood-streaked saliva, high fever, and rapid pulse rate; X-rays confirm solid material in lung tissue
23. Scarlet fever Patient B: 6 years old; mother thought child had a slight cold until a red rash broke out; child is listless and has a slight fever
24. cholera Patient C: recently traveled to an undeveloped country and unknowingly consumed contaminated food and water; proper toilet facilities were nonexistent; exhibits severe muscle cramps and dehydration
25. Typhoid fever_ Patient D: food handler in rural areas where proper toilet facilities are not always available; exhibits a very high fever and chills; blood is in his stool
26. gonorrhea_ Patient E: 30 years old; recently discovered a whitish fluid being discharged by penis; has had severe pain in urination for the last several weeks; additional tests have shown that inflamed testes have resulted in sterility
27. tetanus Patient F: teenager walking barefoot in a construction area has been punctured with a rusty nail; several days later he exhibited mild convulsions that rapidly became more severe
28. botulism Patient G: has recently eaten food from a damaged can; has difficulty seeing, swallowing, and breathing
29. What type of drug is most likely going to be used to treat all of these patients? antibiotic