3.2.1 test hbs

any infectious agent that can cause disease. can be living or non living and can be either visible to the naked eye or only with a microscope

pathogen

causes normal proteins in the brain to fold abnormally

prions

non-living, submicroscopic proteins

prions

consumption of meat tainted with this, medical equipment, and corneas/ organs from infected agents are ways this pathogen can be contracted

prion

how can you prevent the spread of prions

properly clean and sterilize medical equipment and inform prion-infected individuals to not donate their. organs or tissues.

give an example of a prion

creutzfeldt-jakob disease (CJD) causes dementia, walking difficulties, hallucinations, etc.

what pathogen invades into cells, causes tissue damage, and produces harmful toxins

bacteria

how is a bacterial infection diagnosed

physical examination and clinical lab testing

ex of bacterial infection

myobacterium causes tuberculosis

how can bacteria be contracted

depends on type; may occur through an orifice, through a wound, ingestion of contaminated food/ water, inhalation, sexual contact, or imbalance in normal flora

how can bacteria be prevented

vaccines, maintenance of sanitary conditions, and proper personal hygiene

living, microscopic, unicellular, prokaryotic organisms

bacteria

Living, multicellular, eukaryotic worms. Both microscopic and macroscopic varieties exist.

helminths

what damage do helminths cause

deprive the host of essential nutrients found in food and can cause tissue and organ damage

how is an infection from a helminth diagnosed

microscopic examination of fecal material or blood to look for the presence of the worms.

example of helminth

Taenia, a tapeworm infection, results in nausea, loss of weight, abdominal pain, loss of appetite, diarrhea, weight loss, and malnutrition.

how is a helminth contracted

The method of infection depends on the type of worm. Infection may occur through consumption of contaminated foods or water or by being bit by an infected insect.

how can an infection from a helminth be prevented

Varies depending on the type of worm, but includes avoiding:

• Exposure to food or water contaminated with feces from a person or animal infected with a worm

• Ingestion of meat from an animal infected with a worm

• Insect bites

what type of damage does a virus cause

host cells and tissues are destroyed

Non-living microscopic agents made up of an outer protein shell, called a capsid, and either DNA or RNA.

viruses

how is a virus diagnosed

Physical examination and clinical laboratory testing.

example of a virus

The influenza virus, the flu, affects the respiratory system.

how can a virus be contracted

The method of infection depends on the type of virus. Infection may occur through touch, saliva, blood, or sexual contact. Viruses cannot replicate on their own. To reproduce, they infect cells and take over the host cells’ protein synthesis processes.

how to prevent contracting a virus

Vaccines and proper personal hygiene.

treatment for prions

There is no cure for prion diseases, but medications can slow the progression of the disease.

bacteria treatment

Antibiotics can be used to treat bacterial infections.

virus treatment

Antivirals may be used under certain circumstances. Over-the-counter treatments do not treat the infection but can sometimes relieve symptoms. These include pain relievers, decongestants, and cough syrups.

helminth treatment

Deworming medications.

Living, microscopic, single-celled, eukaryotic, animal-like organisms.

protists

protist damage

cause tissue and organ damage

name the six main pathogens discussed

bacteria, protists, helminths, prions, viruses, fungi

how is a protist infection diagnosed

Microscopic examination of fecal material to look for the presence of the protists.

how is a protist contracted

Infection typically results through the ingestion of food or water that has been contaminated with feces from an infected organism. Protists infect the digestive tract, blood, or organs of the body depriving a host of essential nutrients found in food.

how to prevent a protist infection

Maintenance of sanitary conditions and proper personal hygiene.

treatment for a protist infection

Some infections can be treated with antiprotozoal medication.

Living, multicellular, eukaryotic organisms. Both microscopic and macroscopic varieties exist.

fungi

examples of fungi

Fungi include yeasts, mildews, molds, and mushrooms.

fungi damage

Infection can result in tissue damage.

how is fungi diagnosed

Microscopic examination of tissue taken from the infected area, or blood taken from the host, to look for the presence of the fungi.

how is fungi contracted

Some forms infect when the spores of the fungi, the reproductive cells, are inhaled or land on a host.

prevention from fungi

Avoiding contact with an infected host.

fungi treatment

Antifungals

where might you encounter each of the agents on an adventure trip - prions, bacteria, helminths, virus, protists, and fungi

prions: contaminated food, med equipment, animals

bacteria/ virus: bug bites, open wounds

helminths: contaminated food/ water, bug bites

protists: dirt, contaminated food/ water,

fungi: forest floor

what protects the eyes

eyelids, lashes, eyebrows

what protects internal organs and pathogens from getting in the body

skin

epidermis

top layer of the skin that provides a barrier, makes new skin, and gives skin color

dermis

the middle layer of the skin that contains collagen and elastin, grows hair, makes oil and sweat, and contains blood vessels and nerve endings

subcutaneous layer; hypodermis

the bottom layer of the skin consisting of fat that cushions muscles and bones and helps to regulate body temperature

avascular means

no blood vessels

vascular means

has blood cells

is the epidermis avascular or vascular

avascular

are the dermis and hypo-dermis avascular or vascular

vascular

thickest layer in skin

dermis

does the dermis or hypo-dermis have larger blood vessels

hypo-dermis

keratinized cells are

water proof

which part of the epidermis has keratinized cells

the upper epithelial cells

messiner’s corpuscle senses

light touch

pacinion’s corpuscle senses

pressure

sweat glands help with

thermoregulation

oil glands empty into the

hair follicle

another name for an oil gland

sebaceous gland

what contracts in the cold allowing for heat to produce and therefore leads to goosebumps

arrector pilli muscle

an oil gland overproduces during ______ and underproduces during ________

puberty; old age

flora:

fauna:

plant; animal

why is the skin important and what roles does it play

body’s primary barrier against physical insults and microbial pathogens. maintains homeostasis and induces immune responses. protects from pathogens, regulates temperature, and repels water

how does the way skin cells reproduce help skin protect your body from invaders

the epithelial cells in the epidermis divide, and the dead cells move to the surface which play a major role in the skin’s barrier and defense

nerve endings detect

touch, pressure, and pain

a 3rd degree burn would require a

skin graft

a second degree affects what layer(s) of skin

epidermis and dermis

when the body’s immune system overreacts to an infection causing inflammation- swelling, red (due to blood moving to the infection area)

sepsis

organs in body begin to malfunction; blood pressure lowers; inflammation continues

severe sepsis

what is blood pressure

pressure in arteries due to the beating of the heart

extremely low blood pressure that does not respond to IV fluids

septic shock

what does the T in the TIME acronym stand for

temperature: higher or lower than normal

what does the I in the TIME acronym stand for

infection: signs and symptoms of an infection (swollen lymph nodes) it is warm, red, swollen,

what does the M in the TIME acronym stand for

mental decline: confused, sleepy, difficult to rouse

what does the E in the TIME acronym stand for

extremely ill: severe pain or discomfort

bottom layer of the epidermis consists of

basal keratinocytes

the top layer of the epidermis consists of

corneocytes

which cell divides frequently in the epidermis

basal keratinocytes

dead cells in epidermis

corneocytes

corneocytes help with the ______ of the skin

barrier

what secretes elastin and collagen fibers from a dense extracellular matrix

fibroblasts

lymph fluid is drained through __________ to _____________

lymphatic vessels; lymph nodes

immune cells are activated in what after pathogen encounter

lymph vessels and lymph nodes

cyte means

cell

function of the immune system

protect body from sickness

function of the lymphatic system

maintaining fluid levels in the body, absorbing fat from the digestive tract, protecting the body from pathogens, transport/ remove waste from lymph fluid

glands in the immune system that usually enlarge in response to a bacterial or viral infection, trapping bacteria.

lymph nodes

what is lymph

a usually clear fluid that passes from intercellular spaces of body tissue into the lymphatic vessels

arterioles deliver oxygenated blood to the

capillaries

all lymph vessels lead to a

lymph node

a network of thin, tube-like structures that carry lymph fluid throughout the body

lymph vessels

filters blood of foreign cells and old red blood cells in need of replacement. a person missing this part gets sick more often than someone who has it

spleen

what eats up the pathogens in lymph

lymphocytes

bone marrow makes

b cells

the thymus makes

t cells

stores lymphocytes

lymph nodes

produces lymphocytes

spleen

what traps pathogens

tonsils