BIO 217 Quiz 4

upper respiratory tract

• nose

• mouth

• pharynx

• larynx

nose & mouth

air enters body, oral & nasal cavity

pharynx

passgeway

largynx

voice box, passageway

lower respiratory tract

• trachea

• bronchi

• bronchioles

• alveoli

trachea

windpipe, connects larynx to bronchi, passageway

bronchi

2 main branches entering each lung, major air passage to lungs

bronchiole

minor branches from bronchi

alveoli

air sacs of lung for gas exchange

acute otitis media (ear infection)

auditory tube drains fluid from middle ear into pharynx to maintain ear pressure, pathogens trapped in middle ear if tube blocked, young children more prone (narrow/horizontal tube)

infection in upper respiratory tract

causes inflammation in nose/throat, excess mucus production

• tonsilitis

• laryngitis

• sinusitis

tonsilitis

inflamed tonsils, pathogens infect tonsil, swollen/red/sore tonsils, symptom of strep throat, ex: Streptococcus pyogenes bacteria

Streptococcus pyogenes

bacteria causing tonsilitis

laryngitis

pathogens infect larynx, inflammation of vocal cords, temporary voice loss, ex: rhinovirus & influenza virus

viruses causing laryngitis & sinusitis

rhinovirus & influenza virus

sinusitis

inflamed sinuses, pathogens infect sinus lining (inflammation/swelling), mucus drainage blocked, cause pressure & sinus headaches, ex: rhinovirus & influenza virus

upper respiratory tract protection mechanisms

• mucosal protection

• saliva

• lysozyme

• immunoglobulin A (IgA)

mucosal protection

mucosal lining of mouth & pharynx remains moist (via saliva), remove pathogens before attaching to tissues, push pathogens towards digestive tract & destroyed in stomach, upper respiratory tract

saliva

contains lysozyme & IgA, upper respiratory tract

lysozyme

antimicrobial enzyme, breaks down peptidoglycan bacterial cell walls, destroys bacteria/prevents infections, innate immunity, upper respiratory tract

immunoglobulin A (IgA)

antibody binding to pathogens, prevents pathogens from attaching to/entering mucosal cells, adaptive immunity, upper respiratory tract

diseases in lower respiratory tract

• bronchitis

• pneumonia

bronchitis

inflamed/mucus filled bronchi, pathogens infect bronchi linings triggering inflammation & increased mucus production, swollen airways/excess mucus prevents air movement in/out lungs, coughing/chest discomfort, ex: influenza virus

virus causing bronchitis

influenza virus

pneumonia

fluid filled alveoli, pathogens infect alveoli, inflammation causes fluid/immune cells accumulating inside alveoli & prevent gas exchange, coughing/fever/shortness of breath/crackling sounds/decreased O2 levels, ex: Streptococcus pneumoniae bacteria & influenza virus

pathogens causing pneumonia

• Streptococcus pneumoniae bacteria

• influenza virus

lower respiratory tract protection mechanisms

• mucous production

• mucociliary escalator

• cough reflex

• macrophages

mucous production

trap pathogens in airways, lower respiratory tract

mucociliary escalator

cilia lining in trachea/bronchial tubes push pathogens in mucus up toward pharynx via breathing, innate immunity, lower respiratory tract

cough reflex

mucus traps pathogens (influenza virus)/dust/particles to be coughed & expelled out, lower respiratory tract

macrophages

fixed in alveoli for phagocytosis, lower respiratory tract

respiratory disease transmission route

droplet transmission, short distances, coughing/sneezing/talking/singing

respiratory disease prevention

wear masks (asymptomatic carriers), bigger particles fall quicker/smaller particles airborne longer, influenza/common cold viral diseases

influenza virus

negative strand RNA, enveloped virus, droplet transmission via respiratory particles, <2 days incubation, wash hands/wear masks/vaccinate to prevent, consistently high rates of hospitalization & deaths yearly (mutates)

influenza virus entry

hemagglutinin

hemagglutinin

influenza virus surface glycoprotein for entry, recognizes/binds to sialic acid residue covering host cell receptors, begins endocytosis

influenza virus exit

neuraminidase

neuraminidase

influenza virus surface enzyme for exit, cleaves sialic acid residue from host cell glycoproteins, release newly formed influenza virus to infect other cells

influenza virus diagnosis

rapid tests

• control: confirms correctness of test

  • formation of line = positive

• test: your sample

influenza virus treatment

tamiflu

tamiflu

binds to active sites of viral neuraminidase, influenza virus remains attached to sialic acid & destroyed by phagocytic cells, prevents viral capsid release from host cells

vaccine effectiveness

refers to how vaccine performs in general population after release of vaccine, reduces cases among vaccinated people, depends on environment/ages, doesnt protect all strains of influenza (mutates every year)

type A influenza

2 strains, more common strain, replicates faster, causes more severe symptoms

antigenic drift

minor changes in hemagglutinin/neuraminidase occur, makes influenza hard to control each year

vaccine efficacy

determine how well vaccine is at reducing risk of developing infection under controlled clinical trial conditions before releasing vaccine, healthy individuals at certain age