Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Final - Microbiology > Final-Micro Study Cards > Flashcards

Final-Micro Study Cards Flashcards

1
Q

What do all viruses have in common?

A

1-Can only replicate inside living (host) cells
2-Enter (spikes), replicate inside the cell
3-Leave cell by either bursting out of the weakened host cell (Naked Viruses), or budding off from the host cell’s plasma membrane (Enveloped Viruses)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Naked viruses have what 3 structural features?

A

1-Core that holds either DNA or RNA (not both) with the genetic-coding instructions for producing more viruses (viral replication)
2-The nucleic acid core is surrounded by a protein called the “CAPSID”
3-External SPIKES - the “keys” that slip into receptors on the cell’s surface - stick out from the capsid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the #1 Sexually-Transmitted Disease (STD) in the USA

A

HPV cause Genital Warts and are the cause of Cervical Cancer in females

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the 4 structural features of Enveloped viruses?

A

1-They have either DNA or RNA, with viral-replication genetic-coding instructions, in the CORE
2-There is a CAPSID protein shell surrounding the core
3-There is an ENVELOPE, which is the lipid bi-layer plasma membrane stolen from the host cell that the virus budded from.
4-There are key-like SPIKES that stick out from the Envelope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What kind of virus causes Chickenpox?

A

Enveloped herpes virus called Varicella

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How is Chickenpox contracted and what happens?

A

Viral particles are inhaled, infecting the nose and throat and then “seeding” the bloodstream, before infecting the skin, where an itchy rash of virus-filled blisters erupts most on the face and the upper torso.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What can the opened blisters from Chickenpox do?

A

Create the risk of a serious Secondary Bacterial skin infection caused by Staphylococcus aureus or Streptococcus pyogenes.
There is an effective live, attenuated vaccine to prevent a chickenpox infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What virus re-emerges as shingles?

A

Chickenpox: Virus never leaves the body, migrates from the skin into sensory nerve fibers.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How do Shingles occur?

A

When the virus Re-Activates within a nerve cell, followed by migration of viral particles back down the sensory fibers to cause the eruption of a virus-filled rash of blisters on the skin.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Can Shingles be prevented?

A

Yes, if a child receives the Chickenpox vaccine and never gets chickenpox or if an adult over 50 gets a shingles vaccine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What causes Oral Herpes?

A

Herpes simplex virus-1which is the leading cause of infectious blindness in the USA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How is the HSV-1 infection similar to a Varicella infection?

A

HSV-1 viral particles will migrate up a sensory nerve fiber and then lie dormant in the cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How is HSV-1 different than the Varicella infection?

A

Re-activates much more often - maybe 1 or more times a year. Re-activation of HSV-1 appears to be triggered by stress (emotional, ultraviolet light, etc.)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is Herpetic Keratitis?

A

HSV-1 infection of the Cornea and is the leading cause of infectious blindness in the USA.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How are health-care workers at risk of Herpetic Keratitis?

A

Health-care workers working with a herpes-infected patient are at risk of transmitting the virus to themselves when examining patients-even with gloves on.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is Viral Encephalitis?

A

Encephalitis is inflammation of the brain itself. Usually the microorganism or its toxin must be able to cross the blood-brain barrier to reach the brain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is Rabies?

A

Rabies results in fatal viral encephalitis, transmitted to humans by other infected mammals.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What happens when infected by Rabies?

A

Virus accumulates in salivary glands and is transferred when bitten or scratched by a “rabid” animal.
Once bitten the virus enters peripheral nerves at the wound site and migrates through the NS to reach the brain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

A potentially Spleen-rupturing viral infection of B-Lymphocytes is?

A

Infectious Mononucleosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How do you contract Mononucleosis?

A

Develops after a Herpes virus. It is transmitted in saliva between kissing teens and young adults, and thus is referred to as the “Kissing Disease”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How does the Mononucleosis effect the body?

A

Virus infects B-lymphocytes that accumulate in the Spleen which enlarges and is at risk of rupture. A ruptured spleen will rapidly lose blood and can lead to potentially fatal Cardiovascular shock.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What cause the “Flu”?

A

Enveloped Influenza Virus. Hemagglutinin is the H-spike, used as the Key that binds to a receptor on the surface of a Ciliated Cell of the respiratory tract so the virus can gain entry into the cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is Neurominidase?

A

The N-spike: A surface enzyme that the virus needs to undock/cleave from the host cell when the virus is ready to bud-ff to find another cell to infect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What kind of cell does the flu virus infect?

A

Ciliated Cells lining the respiratory passages leading to the lungs’ air sacs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What happens after the flu virus infects the ciliated cells?
The loss of the mucociliary escalator creates an "opportunity" for inhaled bacteria to NOT be caught, leading to infiltration of the lung alveoli/air sacs by bacteria, which causes BACTERIAL PNEUMONIA
26
What does pneumonia do to the body?
Causes inflammation in the air sacs ("alveoli") and the accumulation of fluid and debris prevent the exchange of oxygen and carbon dioxide between the air and the bloodstream. This can lead to suffocation, and results in about tens of thousands of flu-deaths in the USA annually.
27
The flu virus MUTATES in 2 ways: First
Antigenic Drift: "natural" annual mutations amoung the 8 genes in the virus, changing the "H" spike so it is still able to dock onto a host cell but is not recognized by any memory cells produced during previous influenza infections or vaccines.
28
2nd Mutation of flu virus:
Antigenic Shift or Genetic Re-Assortment: Starts with the entry of flu viruses that normally infect different animals gaining entry to the same "new" host cell at the same time. EX: bird-flu GENES and human-flu GENES can be swapped. The original human virus has sphere-shaped H-spikes and the original bird virus has triangle-shaped H-spikes. After swapping genes for the H-spikes inside pig cells, the new human virus has human and bird spikes, which is difficult for the human immune system to easily recognize and attack.
29
A Poop-Transmitted Respiratory Virus?
Hantavirus-found in mouse poop and if inhaled-the greatest risk is cleaning out a shed or garage where mice were staying-can quickly lead to a deadly lung infection and pneumonia in any adult. Has almost a 50% fatality rate in young adults.
30
What kind of virus is Hepatitis A and how is it transmitted?
A Naked virus transmitted via the fecal-oral route. This is the most common cause of hepatitis in the USA. Acute Infection with no chronic problems You can get a Gamma globulin injection - passive artificial immunity after exposure to HAV There is a vaccine available to protect from infection.
31
What kind of virus in Hepatitis B and how is it transmitted?
An Enveloped virus: causes a chronic HBV infection. 50% are transmitted parenterally and 50% are contracted sexually, making HBV a sexually transmitted disease STD
32
What are some symptoms of Hepatitis B?
Chronic liver problems, liver cirrhosis (scarring) or liver cancer. Can be continuously shed into the circulatory system, making HBV a Contagious "blood-borne disease" There is an effective vaccine, Recombivax, to prevent infection and liver cancer
33
What kind of virus is Hepatitis C?
An Enveloped virus which can cause chronic liver infection that can lead to cirrhosis and/or liver cancer and most cases are transmitted parenterally.
34
How long can Hep C survive in the environment?
HCV can survive in the environment at least 16 hours- and maybe up to 4 days on fomites. There is no vaccine for HCV and treatment protocols including Interferon, Ribavirin, and more recently Protease Inhibitors have been very effective.
35
What is Viral Enteritis?
A viral infection of the small intestines
36
What happens in the small intestines?
Where almost all absorption of ingested nutrients occurs and intestinal infections usually result from "fecal-oral" transmission, requiring a critical number of microorganisms surviving passage through the stomach acid.
37
What are the symptoms of a viral infection of the small intestines?
The victim suffers abdominal cramping, nausea, vomiting, fever and diarrhea due to inflammation and damage to the wall of the intestines-called enteritis.
38
This causes most viral intestinal infections of children?
The Naked Rotavirus
39
This causes most viral intestinal infections of adults?
The Naked Noro Virus
40
What does HIV stand for and what does it infect?
Human Immunodeficiency Virus and it primarily infects Helper T-Lymphocytes. Once in the bloodstream, its primary target are Helper T-cells also known as "CD4 cells" because they have the CD4 receptor that HIV's spikes bind to in order to gain entry into the cell.
41
What happens whens HIV effects the Helper T-cell?
As the Helper T-cells disappear, the victim's immune system is unable to fight off infections.
42
What do most HIV victims die of?
Respiratory infections, like Tuberculosis
43
What do Gram-Positive Bacteria and some Gram-Negative release?
EXOTOXINS that cause illness
44
What do Gram-Negative Bacteria have?
ENDOTOXIN in the LPS coating around the cell wall, and as the Gr- bacteria die, the ENDOTOXIN is released, causing the illness.
45
Single-celled EUKARYOTIC microorganisms?
Protists
46
What is the greatest single infectious cause of blindness in the Developing World?
Trachoma
47
What is Trachoma?
An infection of the Conjunctiva caused by Chlamydia trachomatis.
48
What causes Trachoma?
an obligate-intracellular Gram-negative bacterium
49
Why are drops of tetracycline applied to the eyes of a newborn to prevent infection?
Because a pregnant female may not realize she has a chlamydia infection.
50
A direct infection of the cornea by an Amoeba is called?
Amoebic Kerititis
51
What is Amoebic Kerititis?
A direct infection of the cornea by an Amoeba-A water living single celled that is introduced under a contact lens by the victim. Can be very difficult to treat and can lead to blindness in the eye, requiring a corneal transplant.
52
Inflammation of the connective tissue coverings over the brain and spinal cord?
Bacterial Meningitis
53
What are symptoms of Bacterial meningitis?
Nausea, vomiting, diarrhea and severe headache, and a stiff neck: can be serious and fatal (unlike Viral meningitis).
54
The most-worrisome infection caused by the Gram-negative diplococcus?
Neisseria meningitidis
55
What does Neisseria meningitidis cause?
Meningococcal meningitis and Meningococcal sepis which is when the bacteria spread throughout the body, and their ENDOtoxin is shed.
56
Meningococcal sepis results in what?
Spread of the organism through the circulatory system and the release of large amounts of endotoxin as the bacteria die and shed their LPS.
57
Meningococcal sepis can also cause?
Septic Shock: severely damaging blood vessels throughout the circulatory system leak blood, some of which collects as pools in the skin that give the characteristic large purplish skin spots (called petechiae) covering the body.
58
Highest Risk Groups of Meningitis? Where do the bacteria come from?
Young children and young adults in group setting like college. 15% of the human population consists of individuals who are carriers of the bacteria in their throats.
59
This is the result from EXOtoxins that disrupt breathing?
Tetanus and Botulism
60
Tetanus Toxin is produced by?
Clostridium tetani
61
Botulism Toxin is produced by?
Clostridium botulinum
62
What type of bacteria are both Clostridium tetani and Clostridium botulinum?
Gram-positive, anaerobic, endospores-forming environmental bacteria
63
What does Tetanus do to the body?
Causes spastic paralysis - including locking up the diaphragm.
64
What happens when Tetanus toxin enters the body?
Enters the blood supply and crosses the blood-brain-barrier. In the brain, the toxin disrupts the brainstem center that regulates skeletal muscle tone-and its Respiratory Center that regulates breathing.
65
Who is at greatest risk of Tetanus?
The unvaccinated: the vaccine against the inactivated tetanus toxin is effective for on 10 years.
66
Causes Flaccid Paralysis, including a limp diaphragm?
Botulism: the most powerful poison known - does not cross the BBB
67
What happens when Botulism enters the body?
This toxin enters the terminals of the peripheral motor nerve fibers and prevents the release of their neurotransmitter (ACH) from the terminals supplying skeletal muscles.
68
What does Botulism lead to?
The muscles are unable to contract without the chemical signals and become flaccid, or limp. If the condition progresses, the Diaphragm is unable to contract and the person suffocates.
69
Who is at greatest risk of Botulism?
Children up to 1 year of age by ingesting Clostridium botulinum endospores in soil and jars of honey and developing "Infant Botulism" which accounts for almost 75% of botulism cases in the USA.
70
A bacterial infection of one or more of the heart valves?
Infective endocarditis
71
Form of Infective endocarditis?
Rheumatic Heart: can follow a childhood case of "strep throat".
72
What happens if the Infective endocarditis infection spreads into the bloodstream?
Can trigger the production of antibodies that not only remove the infection but also might attack a heart valve, leaving a damaged valve that puts the individual at risk of "Subacute Endocarditis" at a later point in life.
73
What is Subacute Endocarditis?
A slow-developing but serious and sometimes fatal, colonization of previously damaged heart valve(s) by otherwise harmless oral bacteria in individuals who have Rheumatic heart.
74
Who is at risk of Subacute Endocarditis?
Those with earlier valve-damage and can be prevented by the administration of Prophylactic use of antibiotics before dental surgery and/or professional teeth-cleaning.
75
Chaga's Disease is?
Heart wall destruction by a protist
76
How is Chaga's Disease caused?
by a single celled parasite called a trypanosome, which usually inhabits mud huts in rural tropical landscapes of Central and South America.
77
How is Chaga's Disease Transmitted?
The microbe is passed in poop from the "kissing bug" to the skin's surface and then the victim scratches the parasite into the small puncture left by the bug.
78
What happens once the parasite trypansome enters the body?
The protozoa enter the bloodstream and infiltrate the heart wall (the myocardium), weakening to the point where it can "explode" and cause rapid cardiovascular shock, killing the victim.
79
What is pertussis?
Better known as "Whooping Cough" in children, and is caused by Bordetella pertussis.
80
What is Bordetella pertussis?
an EXOtoxin-producing Gram-negative rod that adheres to and destroying the ciliated cells of the respiratory tract, leading to severe coughs, followed by "whoops" of sucking air in children - and sometimes broken ribs
81
Adults who do not receive a "booster shot for Pertussis are at risk of what?
100-day cough: their ciliated cells are trashed by Bordetella pertussis, and although the bacteria are eleminated within a couple of weeks, it can take over 3 months for the respiratory lining to recover.
82
What is Tuberculosis?
A lung infection, caused by the waxy-coated Mycobacterium tuberculosis. It is a disease that has 3 stages.
83
What are the 3 stages of TB?
Active, Latent and Re-Activation
84
What happens in the Active stage of TB?
10%or less of infected individuals, TB starts as an Active lung infection but as bacteria are engulfed by lung Macrophages their waxy coat prevents destruction. The Macrophages die, but the bacteria live for many years inside the lungs.
85
What happens in the Latent stage of TB?
T-lymphocytes and calcium surround the bacteria and dead Macrophages to wall off the infection, which forms Granulomas inside the lungs, visible with an X-ray. Most infected individuals live out their lives at this stage.
86
What happens in Re-Activation stage of TB?
The granulomas break down and the bacteria spread through the lungs and body (called "Consumption") During the re-activation phase in the lungs, the bacteria can be coughed out, making the victim contagious (particularly to health-care providers)
87
What 2 groups are at highest risk of TB re-activation and spreading the disease through coughing?
Elderly: TB can be re-activate when the defensive wall breaks down HIV infected AIDS victims: the loss of Helper T-cells leads to the ability of the bacteria to "break out". TB contributes to up to 50% of the deaths of AIDS victims.
88
How is a primary TB infection treated?
6 months of daily antibiotics
89
What causes most bacterial infections of the small intestines -ENTERITIS- of people in the USA?
Caused by "enteric" Gram-negative rods of humans or other animals.
90
Most common cause of bacterial infections of the small intestines in the USA is?
Campylobacter jejuni-commonly found on commercial poultry.
91
How is Salmonella transmitted?
Contaminated poultry and un-pasteurized milk. It is also a resident of Reptiles, so children should be advised to wash their hands after handling turtles or other reptiles.
92
E.Coli 0157:H7 is found and transmitted how?
virulent species found in the digestive tract of Feces of Cattle.
93
How are commercial foods contaminated by E.Coli?
During the slaughtering of Cattle: fecal matter can contaminate the meat(hamburgers in particular are a risk) "Runoff" from "cow pies" with E.Coli can reach irrigation systems and be sprayed over commercial vegetables (like spinach).
94
What does E. Coli do?
It is extremely virulent because it releases a "shiga toxin" (the plasmid with the toxin was passed to E.coli from shigella bacteria) that can enter the bloodstream and cause Hemolytic Uremic Syndrome.
95
What is Hemolytic Uremic Syndrome?
A widespread rupturing of red blood cells and irreversible damage to the kidneys that may be fatal or result in the need for a kidney transplant.
96
What is Giardiasis?
the most common water-borne parasitic infection of the Intestines.
97
How is Giardia contracted?
swallowing the protozoa or cysts of Giardia lamblia, usually in contaminated mountain water.
98
In females, the site of infection for most STDs starts where?
Cervix: the tissue at the base of the uterus and just beyond the vagina
99
Chlamydia is caused by?
obligate intracellular, Gram-negative Chlamydia trachomatis.
100
What is the #1 bacterial STD in the USA?
Chlamydia
101
What is Gonorrhea and how is it caused?
Common bacterial STD caused by the Gram-negative dipococcus, Neisseria gonorrhoeae
102
Signs and symptoms of Chlamydia and Gonorrhea?
Men have painful urinations and penile exudates and women may suffer from PID
103
What is PID?
Pelvic Inflammatory Disease: causes inflammation of the female reproductive tract, particularly the oviducts, also called uterine tubes or Fallopian tubes. The tubes become inflamed and can scar and the woman can become infertile as a result because her eggs can't reach the uterus.
104
How is West Nile Virus spread?
The virus passes from mosquito's saliva into victims bloodstream during "meal".
105
Once the West Nile Virus enters the victims bloodstream what happens?
The virus crosses the blood-brain-barrier, it then inflames the brain. This could leave a victim permanently paralyzed or be fatal, which occurs mostly in the elderly. There is no treatment or cure.

Final - Microbiology (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions