Microbiology in Human Affairs: Exam 3- Wainwright Spring 2023

What is immunology?

The study of the body's defenses against specific pathogens

What are innate agents of resistance?

Methods and agents of defense against pathogens that we naturally have.

Why is having healthy skin important to our immune system?

Most pathogens cannot penetrate through the skin, which gives us a defense against disease.

What is the outer layer of skin (stratum corneum) made up of?

Keratin fibers (dead skin)

Why is a burn patient so difficult to take care of in a healthcare setting?

The constant dehydration and lack of resistance to outside microbes weakens the immune system exponentially.

What are mucous membranes?

Moveable and sticky membranes that trap "bugs", preventing them from attaching to living cells. If it can't attach, it can't infect.

Why are colds so much more common in the winter time?

Due to the cold and dry nature of the air in the winter time, mucous membranes dry out. When they are dry, they lose their sticky and moveable characteristics which prohibit them from trapping microbes. This makes it easier for microbes to attach and infect healthy, living cells.

What is hydrochloric acid?

stomach acid

What is the cause of stomach ulcers?

Stomach acid coming in contact with stomach lining, presence of helicobacter pylori, and being urease positive.

What is one of the largest causes of intestinal worms?

Eating undercooked pork.

What percent of the population has intestinal worms?

1/7

What two viruses are notorious for passing through the stomach and infecting the intestines?

Rhodovirus and norovirus

Why is lacrimation (tears) so beneficial to the immune system?

they contain lysozyme, which is a major protein that offers many antimicrobial benefits

Where do most respiratory infections begin?

The eyes. The eyes are directly exposed to the world at all times, and are connected to the nasal passages.

Are most of the microbes that trouble us Gram positive or Gram negative?

Gram positive

What are leukocytes?

White blood cells. They fight against infections in the body.

Where are White blood cells created?

The bone marrow

What are the four signs of inflammation?

Rubor- redness

Tumor- swelling

Calor- warming

Dolor- pain

Why are anti-inflammatory drugs actually more harmful than helpful?

Inflammation is what's actually fighting the infection. If we suppress it, the healing process will take longer. It's best to let the infection and inflammation run its course.

Why does inflammation cause redness?

In the event of an infection, we need more blood (RBCs) to go to that area. More blood pooling= redness to the skin

Why does inflammation cause swelling?

In order to get more blood to the site of infection, our blood vessels dilate, causing the area to swell.

Why does inflammation cause the area to get warmer?

Blood is warmer that the rest of the body. More blood to the area means that area will feel warmer.

Why is inflammation painful?

When blood vessels dilate, they can press on nerve endings causing pain to the area.

What part of the brain controls the body's thermostat?

The hypothalamus

What is found in the blood that causes the hypothalamus to up the body's temperature?

Interleukin 1

What temperature in adults can cause convulsions?

105 degrees Farenheit

What temperature in adults is typically fatal?

107 degrees Farenheit

Why do we need our body's normal flora?

Our body's normal flora is responsible for resistance to outside pathogens.

What is Clostridium difficile?

A bacteria that causes infectious diarrhea / colitis. It can occur when antibiotics "wipe-out" a person's normal gut flora.

What is the common treatment for C. diff?

Fecal transplant

What is complement?

a group of proteins, that leads to the lysis of invading cells

What are T-cytoxic lymphocytes?

type of white blood cell that can remember what pathogens they've already been in contact with. They often destroy the infected cell.

What is clonal selection?

lymphocytes remember what pathogens they've already been in contact with. When they come in contact with a pathogen, they will clone themselves so the new cell will also know that pathogen. These are memory cells.

What is a B-lymphocyte?

A cell that encounters something foreign and transforms itself into a plasma cell (modified B-lymphocyte.) The plasma cell can make 150,000 antibodies per second.

How long do antibodies stay in your body?

Forever

Why can we not gain immunity to the common cold?

There are too many of them that change constantly. If they are changing constantly, our lymphocytes technically having "seen" them before.

What is a T-helper cell?

These cells will circulate the blood "checking out" foreign things. These cells alone can't actually do anything about a pathogen, but they relay this info through interleukins to the B-lymphocytes.

What activates complement?

Antigen-antibody complex

What are the four outcomes of complement activation?

1. Stimulate phagocytosis: digest and destroy pathogen

2. Stimulate inflammation: gets more agents of immunity at site of infection

3. AAC will stick to the surface of RBCs: RBCs pass through the spleen, where the pathogen will be destroyed

4. Membrane attack complex: Lysis destroys the infection

How do we get antibodies?

By being exposed to the pathogen or disease

What is naturally acquired active immunity?

getting the antibodies by having the disease

What is artificially acquired active immunity?

getting the antibodies by way of vaccine

What is naturally acquired passive immunity?

baby getting antibodies from mother in womb. only lasts about 6 months of life

What is artificially acquired passive immunity?

intentionally exposing baby to pathogens.

15 x 15 vaccine program

Why are some diseases such as mumps and measles still present even though we have vaccines for them?

Vaccines are not 100% effective unless every person in the world gets the vaccine.

What vaccine are some people suspicious of causing autism?

Mumps vaccine

what is lysozyme?

fluid on eyes that keeps them from being infected

autoimmunity

cells destroying themselves

inhibit protein synthesis

aminoglycocides, macrolides, tetracyclines, chloremphenical

Inhibit DNA replication

fluoroguinolone, ciprofloxacin, levofloxacin, ofloxacin

inhibit folic acid synthesis

sulfamethoxazole + trimetoprin

inhibit mycolic acid synthesis

isoniazid, ethambutol, pyrazinamide, streptomycin, rifamycin

antiprotozoan

hydrochloroguine, mefloguine, atovaguine, diiodohyrdroxy chlorroguine

anti-virals

acyclovir, gancyclovir, pencyclovir, remdisivir, oseltamivir, vancyclovir

where do most respiratory infections begin?

nose

where do most GI infections begin?

mouth

pathogen

An organism that causes disease

pathogenicity

ability of an organism to cause disease

invasion

ability to attach to a cell

invasiveness

ability of a bacterial pathogen to rapidly spread through tissue

virulence

severity of disease

routes of transmission

direct (blood,saliva,touch) indirect (aerosol)

portals of entry

mouth, nose, eyes, skin, genital opening, ears

signs and symptoms

sign (can be observed, fever, BP, rash) symptom (feelings, couch,pain,nausea)

reservoir

where disease forms/originates

Transmisability

the ability of a disease to move from one person to another

disease levels in a population

indemic(stays in pop.) epidemic (spreads nearby) pandemic (worldwide)

biological safety levels