Microbiology Test #2

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1

Who invented the microscope? What did he discover? What's some other background info over him?

Antoni van Leeuwenhoek. He discovered protozoans and bacteria at 500x magnification compared to Mr. Hook looking at only 100x mag. Leeuwenhoek was a businessman; not a microbiologist. He liked to grind glass lens and found that he could magnify things by doing this.

2

Who was the first to see cells and how did he do this?

Robert Hook took a section of cork (plant product)and saw that life is composed of cells.

3

Who 1st showed that there can be unicellular organisms?

Leeuwenhoek

4

Who was the 1st inventor of the smallpox vaccine?

Edward Jenner

5

T or F. There is no cure for viral infections but we can cure bacterial infections.

T

6

What is the incubation phase of smallpox and describe it's process of infecting an individual.

Incubation Phase- 12 days. The virus is inhaled (some spread via secretions or contamination of drinking & eating utencils). Virus multiplies in mucosa of upper respiratory tract. Moves to lymph nodes. Enters bloodstream; travels to internal organs. Extensive viral replication. And the virus returns to bloodstream.

7

What are 3 examples of virus's we can't cure?

measels; hepatitis; mumps

8

How long does the Somatic Disease last?

3-5 weeks. Early rashes, fever, and aches. The virus enters skin, multiplies in epidermal cells.

9

Back in the day, what chance did an individual have of surviving smallpox? What does it look like?

50% chance of surviving. It kind of looks like herpes or chicken pox.

10

What is definition of incubation period?

Time it gets in your body until you 1st show symptoms.

11

T or F. Smallpox has a short incubation period.

F. It has a long incubation period (10-12 days)or (1 1/2 weeks). Normally, if you breathe the flu virus, you would show symptoms in (12-24 hrs.)

12

Why can smallpox be used in biological warfare?

b/c of long incubation period. In 12 days, many people can be exposed.

13

How many people did we lose in the 20th century to smallpox?

300 million. The exposed lesions usually caused the death and if they did survive they would have scars from these lesions.

14

What is the ONLY virus to be eradicated?

Smallpox.

15

What are the four properties of smallpox that led to its eradication? Explain each one in detail.

1. Viral Characteristics- It's an exclusive human host (can't survive in animals). It is a SINGLE SEROTYPE (only 1 kind of virus! No strains). Epitopes (the animal and human pox virus are similiar. You make an antibody when given the vaccine and it can recognize both human & animal pox virus's. )

2. Disease Characteristics- A person w/ smallpox is easily recognized by skin pustules. Identification- of sources of contagion allowed quarantine & vaccination of contacts.

3. Vaccine- Stable; inexpensive, easy to administer vaccine. Presence of scar indicates successful vaccination.

4. Public Health Service- Successful worldwide (WHO) program combining vaccination and quarantine.

16

What year was the smallpox extinct?

1978

17

What are the virus's called that cause smallpox and cowpox? What was Jenner's idea for a vaccine?

Variola-smallpox. Vaccinia-cowpox. Both have similiar surface structures that it can trick human immune system into thinking its the same thing. Jenner's idea was to inject a person w/ vaccinia and there will be a localized cowpox lesion & the body develps antibodies to smallpox. He knew that if the person had had cowpox, they wouldnt' get smallpox.

18

What is the term called meant the cowpox and smallpox reacted together?

Cross-reactivity

19

What is the only way to see the smallpox and cowpox virus?

Under an electron microscope.

20

When was the big experiment done to 8 yr old James Phipps to test the smallpox vaccine?

May 14, 1796

21

How was the smallpox vaccine done?

They would stick the needle into the epidermis and deposit ground-up scabs. Putting it in the epidermis makes the immune response very reactive compared to in the dermis.

22

What needle contributed to the success of the smallpox eradication campaign?

The bifurcated needle.

23

T or F. The smallpox vaccine is NOT a cure; it's a PREVENTION.

T. It is given to someone before they contract the virus to build their immune system.

24

How do virus's reproduce? Give some background info. Do the same w/ bacteria.

Virus's depend on a host cell to reproduce. In order to stop a virus, you have to harm your own cells. Virus's are NONCELLULAR. Bacteria can reproduce on their own so we can kill them; not viruses. Bacteria are cellular unlike virus's.

25

What is one of the few vaccines given to someone that is different from what we are trying to protect someone from?

Cowpox! It does give you a lesion and infects you but it usually doesn't spread beyond that.

26

Who are the 2 people to have the smallpox virus that we know of?

The CDC in the US has this virus in the deep freeze and Russia. These two countries decided to keep the virus. There is thought that some other countries have this virus. They know the DNA sequence so it could actually be made. It is NATURALLY EXTINCT.

27

Describe the Rinderpest, or cattle plague virus.

It is a highly infectious viral disease.
High mortality rate of 80-90% of livestock.
Humans CAN'T get this disease.
The vaccine was developed in 156-62.
U.N. declares this virus extinct on 8/8/2011.

28

Why is smallpox an excellent terrorism choice?

b/c of long incubation period. The attackers can leave the country before the 1st case is diagnosed. The 1st symptoms are malaise, fever, headache, and vomiting.

29

Describe the size of the smallpox virus and other characteristics.

The smallpox virus is large; very robust. It can survive outside the human host for days. Its CONTAGIOUSNESS and HIGH FATILITY RATE are what make it so destructive.

30

There was an anthrax attact though the US mail so the government thought that we could be attacked w/ smallpox. Who were the 2 gov. officials who believed that Iraq's potential to produce a smallpox weapon needed UNIVERSAL VACCINATION of the general population?

Cheney and Libby

31

Who was the heroic epidemiologist who led the WHO smallpox eradication program and became Bush's science advisor? What did he think of the smallpox vaccine?

Donald Henderson. He thought universal vaccination would be a terrible idea b/c it could hurt people or kill people. Babies immune system couldn't fight off small pox. Even though it is a vaccination, in some people it gave progressive effects which could hurt or kill.

32

What was the compromise made about the question of universal vaccination b/w gov. officials?

mandatory 500,000 military personal and voluntary vaccination for health care workers. Or "first responders".

33

T or F. Currently, the US has enough stockpile of smallpox vaccine to vaccinate everyone in the US in case of an emergency.

T.

34

What is another pox virus that infects deer and can even affect humans? What is another pox virus that infects monkeys and can affect humans.

Parapoxvirus. Moneypox (CDC traced it back to home in TX who was importing monkeys in & out).

35

Who was the firt person to associate childbed fever w/ the hospital and make people wash their hands? What is childbed fever (puerperal sepsis)?

Semmelweis. It is gram (+) Streptococcus pyogenes that causes strep throat.

36

Describe how Semmelweis figured out what the hospital was doing wrong.

Back in the day, they didn't know there were microbes on a persons hands. A hospital had 2 wings and 1 wing was preferred b/c the other wing had a higher mortality rate. He realized one wing was where med students delivered babies and the midwifes in the other (this was the good wing). Med students would leave autospy and go straight to delivering babies w/out washing hands. He was the 1st to realize that something must be carried on the med students hands. So, everyone was made to wash their hands w/ a CHLORINATED SOLUTION.

37

How would the Streptococcus pyogenes cause the childbed fever?

The infection would begin in the uterus and spread rapidly through body. It was a blood infection.

38

IN 1846, what did the mortality rate decrease to?

15-20%

39

What is a way to match bacteria?

DNA fingerprint

40

Who is the lady known by who came from Ireland to US and cooked for wealthy families in Boston & NY and caused typhoid fever?

Typhoid Mary. Families would get sick but she wouldn't. The infection spread though food when a carrier doesn't wash their hands after using the bathroom. The bacteria lived in Mary's throat and she was a carrier for this disease.

41

T or F. Mary is the 1st documented case of asymptomatic typhoid carrier in the US.

T. Mary had to spend half her life in confinement and was responsible for 53 cases of typhoid fever and 3 deaths.

42

What causes typhoid fever?

Salmonella typhi

43

What did the past Tri Beta President, Miss Stuart, test in her research paper?

She tested Staphlococcus aureus which is commonly found on human hands. She went to all the bathrooms at ASU and swabbed the metal plate from each one. She concluded that the bacteria doesn't have the ability to survive very long on the metal plates.

44

Who is the man associated w/ the pasteurization process and was trying to help the French wine industry when they were having problems w/ their product going bad?

Louis Pasteur. He suggested they warm it up to a temperature to kill microbes.

45

Definition of pasteurization.

To kill microbes w/out damaging the quality of the product.

46

What are the differences b/w pasteurization and sterilization.

Pasteurization- Doesn't imply you have completely gotten rid of every microbe. (water bath-temp. below boiling). It usually doesn't kill spores.

Sterilization- get rid of all life (autoclave) Even kills spores.

47

Why don't we put milk in autoclave?

Too expensive and it will curdle the milk and change the taste.

48

Who is credited for answering this question, "Where did life come from in the 1st place? Does life generate spontaneously or doesn't?"

Louis Pasteur.

49

Explain Pasteur's experiment.

vigorous heat is applied to a solution of microbes so both flasks are free of live cells (sterile). The neck on the 2nd flash was broken and the 1st neck on flask is intact. It showed that you won't get life w/out life already in existence.

50

What is Louis MOST credited discovery? What are 4 more discoveries? What is Louis MAINLY known for though?

1. Discovering anaerobic life and anaerobic bacteria. He was the 1st to discover that some bacteria don't need O2 to survive.

2. 1st to describe microorganisms as aerobes or anaerobes

3. 1st to say exclusively aerobic, at once aerobic & anaerobic, or exclusively anaerobic.

4. He noted the discovery of the presence of refrigent spores.

5. He discovered bacteria to be the cause of anthrax.

6. the rabies vaccine.

51

What is the Pasteur effect?

the inhibiting effect of O2 upon a fermenting process (as one carried by facultative anaerobic organisms)

52

What is rabies?

It is caused by a virus and mainly is a disease of animals. Humans get it when bit by an infected animal. It is almost always fatal. At first, there may not be symptoms. But weeks, or even months after bite, rabies can cause pain, fatigue, headaches, fever, & irritability. Followed by seizures, hallucination, & paralysis.

53

T or F. It takes a short time for the rabies virus to travel to your brain.

F. It takes a while for it to reach the brain. It's one of the few diseases that you can take the vaccine and it can/may prevent you from getting rabies.

54

What are the two forms of the rabies virus?

Furious form (aggressive animals) and dumbform (animals that are sick but not aggressive).

55

Is rabies disease rare in the US? How many cases per year? How many people are vaccinated each year after animal bites? How many deaths worldwide?

It is rare in the US. 1-2 cases in the US per year. 16,000-39,000 people vaccinated. And, 40,000-70,000 rabies-related deaths worldwide (bites from unvaccinated dogs mainly)

56

What does the rabies virus look like under the electron microscope? Decribes how it infects.

Like a bullet. The virus may replicated locally, but then enters the peripheral nervous system, where it passively travels to CNS. Virus next infects the brainstem, cerebellum, and other brain structures. From the brain, the rabies virus can travel along autonomic nerves- causes secretion of saliva, mucous, and tears.

57

What is the oval inclusion body in a brain cell called that are the manufacturing sites of the rabies virus?

Negri body. When they find these, they know the person is positive for the rabies virus.

58

T or F. Rabies attacks nervous system and normally results in death w/in a week of symptoms developing.

T.

59

What are four main animals to carry rabies? Explain each one.

1. Bats: Austin to Houston has the most (+) rabie carrying bats. As bats hibernate so does the rabies in the winter months. Vampire bats in the bottom part of Mexico & South America have a lot of rabies.

2. Skunks: prevalent in the East

3. Raccoons: Most common form of rabie carrier. The government tried out an experiment of dropping food w/ vaccine and it will protect animal when they eat the food. It is prevalent in East Coast.

4. Dogs/Cats: prevalent in northeast.

60

In what country have 10s of 1000s of dogs been killed b/c of rabies?

China

61

What are two other ways to get rabies besides an infected animal bite?

1. lung, kidney, and liver transplants from infected rabie individuals. 2. Drinking the raw milk of rabid cow.

62

Who should get rabies vaccine and when?

1. Preventative vaccination when there is NO exposure. These are people like vets, animal handlers, or cave explorers. The pre-exposure is 3 doses. Dose 1: As appropiate. Dose 2: 7 days after Dose 1. Dose 3: 21 to 28 days after dose 1.

2. Vacciantion AFTER exposure. There are 4 doses. One right away, the 3rd, 7th, and 14th days. A person would also get the Rabies Immune Globulin shot at the same time as 1st dose. They will give you shots in different parts of the body.

63

What were the 1st animals Pasteur used to get the rabie vaccine?

Rabbits. He got their spinal cords b/c he realized it was a neurological disease. The longer you let the spinal cords hang in the drying box, the weaker the virus got. Maybe the virus is still there but is weaker. So he injected a dog w/ the older piece and it would make anitbodies to the virus. Then if you inject that same dog w/ a fresh new rabie infested spinal cord, the dog wouldn't contract rabies b/c they developed their own antibodies.

64

Who was the 1st person to receive the rabies vaccine?

Joseph Meisier. He later worked at the Pasteur Insitute when he got older.

65

Was the smallpox or rabies virus more dangerous?

The rabies virus was b/c they were taking the virus out of the nervous system. Two problems with it were the side effects and the number of shots you had to take.

66

Where is the Pasteur Institute?

In Paris, France. It is the leader in AIDS research now. Pasteur was eventually looked at the savior of the children and his body is in this institute.

67

What is Ozzy Osbourne known for?

1 of 1000 people to have his genes sequenced. He was a member of the Black Sabbath band and bit the head off a bat during a concert. Later, kids found frozen bats and mimicked ozzy. All had to be tested for rabies.

68

Who are the two biggest contributors to give us info over microbiology?

Pasteur and Robert Koch (Germany)

69

What two things did Robert Koch discover and give background info?

He came up with the pure culture and he developed the solid medium concept. He did this by using slices of potatoes and did streak plates on potatoes- some bacteria grew on them. A wife of one of his researchers told him to use the agar in her perservatives (gelling agent).

70

What was the next agent Koch used after the potato? Describe it?

Gelatin. It is a protein and was unsasistifactory b/c of two reasons. 1. It melted @ 37C. 2. Many bacteria can digest gelatin.

71

What was the next agent Koch used after the gelatin?

Agar- It is an extract of algae (a certain seaweed). It is a complex polysacciharide containing sulfated sugars. It can't be digested by most microbial species. IT can't be melted until you boil it.

72

What are the two main properties of agar?

It melts @ 100C. Once it's a liquid, it doesnt gel until temperature drops down to 45C. The low solidifying temp. permits the addition of bacteria to melted agar (45C).

73

What is the definition of Koch's Postulates?

way to prove something is a cause of disease

74

What are the 4 Koch's Postulates?

1. The suspected pathogenic organism should be present in ALL cases of the disease and absent from healthy animals. Observe blood/tissue of diseased /healthy animal. We shouldn't see bacteria in our own blood.

2. The suspected organism be grown in pure culture. Streak agar plate to get colonies of microbes. If you did streak plate on blood, you SHOULD NOT get any microbes.

3. Cells from a pure culture of the suspected organism should cause disease in healthy animals. Innoculate healthy animal w/ cells of suspected pathogen.

4. The organism should be reisolated and shown to be the same as original. Remove blood and do another pure culture.

75

Have we proved HIV causes AIDS?

No, b/c we can't put the virus into a healthy human and we can't test it in animals b/c it doesn't work in them.

76

T. or F. Anthrax is mainly a disease of humans.

F. mainly a disease of animals but can get into humans and kill.

77

Who was important in figuring out anthrax?

Robert Koch

78

What is the bacteria called that cause anthrax and describe it.

Bacillus anthracis. (gram +). Animals typically contract it by ingesting or inhaling spores that can survive in soil for decades. Spores are a survival tool-they don't reproduce.

79

What does anthrax cause?

It causes sudden death (symptom). Another symptom is the animal will bleed out from every oriface. The small blood vessels break and leak out.

80

What are the 3 ways to get anthrax?

inhale, digest, and through cuts. W/out treatment it can be fatal. But early treatment w/ antibiotics is very effective.

81

What year was the big outbreak of anthrax?

2001

82

What are the three forms of human anthrax?

Most get cutaneous anthrax (get it from cuts) or gastrointestinal or pulmonary.

83

What are the symptoms in humans from anthrax and what medicine do they give to those infected?

swelling, black lesions, no fever. They give intravenous penicillin. It is a drug that only works on the growing from of this disease, NOT THE SPORES. Does not work in viruses either.

84

What is the number of metric tons of anthrax the US and Soviet Union have?

US=0.9, Soviet Union=4,500

85

What was pumped into offices of the Senate building when there was thought of an anthrax attack?

Cholorin dioxide. This gas kills even the spore form.

86

Where did they trace the stains of anthrax found in mailed letters?

They traced it to Bruce E. Ivins. We don't know why he did it and sent the anthrax out.

87

What is the term for animal and humans contracted a virus?

zoonosis

88

Why isn't anthrax common in humans?

1. We have a vaccination. 2. We can vaccinate livestock. 3. Better working conditions to people exposed to livestock products.

89

What are 3 characteristics of anthrax that make it an ideal biohazard?

1. the spores- capable of growing into new pathogenic reagents.

2. Virulent- high disease producing capability.

3. High mortality- The good thing is we can give a person an antibiotic for it, not like smallpox which is a virus.

90

Who is the father of natural immunity and what did he promote?

Elie Metchnikoff. He promoted the cellular side of immunity.

91

Who are the two pioneers of cellular and humoral immunology and who goes with which one?

Elie Metchnikoff: cellular (cells are responsible for our protection). Paul Ehrlich: humoral immunity (French term menaing liquid/fluid based). They both got the Nobel prize in 2008 for their achievements in immunity.

92

What are the 2 forms of immunity and describe each one.

Innate Immunity (Natural) Goes after anything in the body; not specific. 1. Phagocyte mediated (Neutrophils, macrophages).

Adaptive Immunity (specific) 1. Antibody mediated (Ehrlich) 2. Cell mediated (lymphocytes) (Metchnikoff).

93

Describe Metchinikoff's experiment how he discovered innate immunity.

He took rose thorns off a thorn bush and put them under the skin of a starfish larvae. This experiment formed the basis of his phagocyte research. he noticed injury attracted a bunch of cells attracted just where the damage was. He also put stuff like anthrax in white blood cells in many animals to show this same concept.

94

Describe tissue macrophages as scavengers.

They are present in liver, spleen, and kidney. They seize upon living cells by means of protoplasmic prolongations to draw them in and digest.

95

Describe macrophages in tubercolosis.

Serve as critical defenders of the host against tubercolosis. W/out a doubt the phagocytes are capable of engulfing these bacteria.

96

Phagocytes (WBC's) have the ability to move. What is the term called where phagocytes sense damage in skin and go to damage and stick by crawling through blood vessels?

Diapedesis

97

Paul Ehrlich thought that microbes have features that attach to them (antibodies). What is the book called that was wrote about him?

Magic Bullet. The term comes from trying to come up w/ a drug that acts like a magic bullet- it finds the microbe, kills it, and it all happens w/out hurting you.

98

How did Paul 1st come up with this magic bullet concept?

By studying Syphillus (STD). It is a bacterium called Treponema pallidium. They used darkfield microscopy to view it. It is a spirochete (flexible).

99

Describe the Treponema pallidium (Syphillus).

1st stage- Get it on genatils, goes into blood, and gets in organs. It is unique b/c we can not streak plate this bacteria. It won't grow on the plate. The original way to cure this bacteria was to use mercury on the skin. This was the 1st treatment.

100

What was the 2nd treatment for Syphillus that is termed the magic bullet?

Paul Ehrlich came up w/ Compound 606 which is composed of small amounts of arsenic and is a chemical drug.

101

Who was the surgeon came up w/ the idea to prevent wounds from getting infected by spraying air/skin w/ a fine mist of carbolic acid producing an antiseptic enviroment?

Joseph Lister

102

What is the product called named after him?

Listerine

103

Do disinfectants used in surgery like alcohol or iodine get rid of every bacteria?

No!

104

What is the difference b/w antiseptics and disinfectants?

Antiseptics= something you use on or in body (not as toxic but designed to get rid of microbes on body). Disinfectants= used on surfaces and kill more bacteria (can't use on humans b/c it's too concentrated).

105

Who discovered Penicillin? And describe it.

Alexander Fleming. Penicillin is an ANTIBIOTIC discovered in early 20th century. The genus Penicillium produces a drug called penicillin. He found that his streak plate bacteria was staying away from a moldlike bacteria. In molds, if you see oil like droplets, that's where the penicillin is at.

106

What is an antibiotic?

microbe producing a drug compound that is toxix to other microbes.

107

What bacteria is very sensitive to penicillin?

Streptococcus which causes strep throat.

108

Who said "fortune favors the prepared mind."

Louis Pasteur

109

What was 1 of the original applicatons for Penicillin?

Gonorrhea. They said it could cure it in 2 hours.

110

T or F. Penicillin is a magic bullet except for people who are allergic to it.

T. about 5% are allergic to it.

111

What was Fleming's 2nd discovery?

The lysozyme. It is an enzyme that a human can make in saliva/mucous/tears. Fleming stuck some of his nasal discharge in the middle of a plate of bacteria. He noticed that there must be something in mucous which dissolved or killed the microbes in its immediate neighborhood.

112

What are two other things Fleming tested his theory on?

He tested his theory on large gram (+) coccus. He saw how the opaque color of the cells turned clear. He also tried it on tears and had the same results.

113

Describe lysozymes more.

It appears lysozymes are made to get rid of microbes in the nose/eyes. It is a natural compound made in our body. Lysozymes are also found in egg whites.

114

T or F. The cell wall is not a unique structure to bacteria.

F. It is a unique structure to bacteria.

115

What is the cell wall pertaining to bacteria? What is an interesting aspect when comparing it to humans that don't have a cell wall.

It is the outside layer of a bacterial cell. Most bacteria have one- humans do not. An interesting aspect is that there are drugs (magic bullet) that hurts bacteria but not humans since there is no cell wall.

116

Describe the differences of the gram (+) and gram (-) cell walls in bacteria.

Gram (+) bacteria have peptidoglycan that sits on top of the cell membrane. They have multiple layers of it. We would expect a drug that affects peptidoglycan could find its target much more readily on gram (+) than (-) since it has so much more.

Gram (-) bacteria have peptidoglycan as well but not as much as gram (+). One huge difference is gram (-) have an outer membrane layer sitting on top of the peptidoglycan. Some drugs aren't good at getting through the membrane to the peptidoglycan layer. The outer layer membrane is similar to the inner layer membrane. There is only a single layer of peptidoglycan.

117

What 2 things does peptidoglycan need to form and describe the chain formation.

It needs N-acetylmuramic acid (NAM) and N-acetylglucosamine (NAG). They hook together in alternating forms (ex. NAM-NAG-NAM-NAG). There are two layers of the NAM-NAG-NAM. Hinging off the NAM's (NOT the NAG) is 4 amino acids called a tetra-peptide chain. Coming off of the 3rd and 4th tetra-peptide's is peptide interbridge composed of gram (+) cells that link the two layers together.

118

Describe the plant cell wall.

Plant cells do have cell walls but they don't contain peptidoglycan. Instead they are composed of cellulose which is a bunch of parallel chains of glucose. **It is not as strong as bacterial cell walls.

119

What is another important polysaccaride found in the exoskelton of things like insects or spiders? Describe it.

Chitin. It's formation is strictly (NAG-NAG-NAG). There is NO (NAM's). It is not cross-hatched and is strong and rigid. But it is still NOT AS STRONG as bacteria cell walls.

120

T or F. Cell walls serve as barriers. Walls are rigid so we can't get big things readily through them. But, the ridigity is important for the integrity of bacteria.

T.

121

What does the cell wall do to break down big substances?

The cell wall secretes enzymes that are transported outside the wall to break down substances. The enzymes hydrolyze the bonds on nutrients.

122

T or F. MIcrobial traits such as thin cell walls are key to survival on land.

F. THICK CELL WALLS. Gram (+) bacteria have extra thick walls that help them survive in places where they would dry out w/out thick wall.

123

Pertaining to the human RBC, describe isotonic, hypertonic, and hypotonic.

First, note that the human RBC doesn't have a cell wall.

Isotonic- water won't go into or out of the cell b/c it is equal. 98% H2O to 2%

Hypertonic- water leaves the cell and it will shrink w/out a cell wall.

Hypotonic- cell gain water and swells.

124

Do bacterial cells react the same way as human RBC's to isotonic, hypertonic, and hypotonic environments?

No! Bacterial cell wall stays the same. As long as the wall stays the same, the bacteria will survive and won't have the same shrinking or swelling characteristics.