What are the functions of the respiratoy system?

Getting gases in and out…Environment to blood = externalBlood to tissues = internal

Olfaction and communication

What structures are necessary?

Respiratory membranes (highly vascular, thin, moist and large surface area)

Introduction to Respiratory System

http://www.listenforjoy.com/art/deepbreath.html

How does your nose contribute?

Olfactory epithelium

Speech… Sinuses Cavities or spaces in bones of skull, empty into the nasal cavity to provide resonance.

Sinusitisinflammation of membranes lining sinus cavities

Introduction to Respiratory System

Respiratory System: GillsWhat features are peculiar to Agnathans?

What all (?) have vertebrates have in common…Pharyngeal pouches meet ectodermal grooves… the branchial membrane then ruptures forming gill slits

In Hagfishes afferent and efferent branchial ducts carry water towards and away from the pharyngeal or gill pouches

What features are peculiar to Agnathans?

Respiratory System: Gills

External nare ends in a blind sac. Consequently, they pump water in and out via the external gill slits.

Respiratory tube facilitates breathing and feeding.

Lamprey are tightly attached to host/prey…

What features are peculiar to Chondrichthian fishes?

Chondrichthian fishes have a spiracle and often 5 pairs of gill pouches except for Hexanchus and Heptanchus

Spiracle of skates and rays primary incurrent, major in most sharks, but minor or lost in fast swimming species

Naked gills (no operculum)

Respiratory System: Gills

Respiratory System: GillsWhat features are peculiar to Chondrichthian fishes?

Demibranchs are the vascular layers found in gill chambers

Pre- and posttrematic demibranchs are supported by an interbranchial septum

Respiratory System: GillsWhat features are peculiar to Chondrichthian fishes?

Holobranchs support and provide structure for primary vasculature

Gill rakers guard the slit

Respiratory System: GillsWhat features are peculiar to Chondrichthian fishes?

Countercurrent flow of water and blood from ventral aorta facilitates diffusion.

Lamella increase surface area (primary and secondary)

http://www.upei.ca/histology/html/fish_gills.html

Respiratory System: GillsWhat features are peculiar to Chondrichthian fishes?

Water flows in via spiracle and mouth (inspiration 1) when branchimeric muscles expand the pharyngeal chamber.

Mouth closes and hypobranchial muscles make the gill chamber expand (inspiration 2)

Constrictors decrease volume of gill chamber forcing water out gill slits (expiration)

What features are peculiar to Bony fishes?

Pharyngeal arches support holobranchs.

Presence of operculum a major difference.

Gills occur in an opercular chamber.

Mouth opens, pharyngeal floor lowers (opercula closed) (inspiration) Opercular chamber volume increases as opercula open

Constrictors decrease volume of opercular chamber forcing water out opercular cleft (expiration)

Respiratory System: Gills

Respiratory System: GillsWhat other functions do gills serve?

Excretion… salts in marine fish, nitrogenous wastes in all fish and CO2 even in lungfish

What features are peculiar to larvae?

3 types:External gills found on larval amphibians and a few types of fish

Filamentous extensions (internal) found on chondrichthian fishes

Internal gills unique to later staged tadpoles

Respiratory System: Gills

http://edoras.duhs.duke.edu/gallery/albums/9/p8120048.jpg

What features are peculiar to larvae?External gills

Internal gills

Respiratory System: Gills

http://fixedreference.org/2006-Wikipedia-CD-Selection/wp/f/Frog.htm

Respiratory System: Nasal structuresWhat is the role of the nares in most fish?

External nares have anterior and posterior regions (incurrent and excurrent aperatures respectively). The passageway leads to blind sacs used for olfaction

Lobe-finned fishes the nasal cavities communicate with the pharynx via internal nares

How are foregut evaginations related to lungs in humans?

These sacs store gases taken directly from the atmosphere (physostomous) or from the blood with no connection to the pharynx (physoclistous)

The gas can be N2, O2, usually some CO2 and/or Argon

Serve as buoyancy devices, also help detect sound.

Respiratory System: Swim bladders

Respiratory System: Swim bladders

Upper Respiratory SystemHow are foregut evaginations related to lungs in humans?

The lung bud is a single evagination that communicates with the pharynx via the glottis

It bifurcates and pushes caudad until they are beside the heart

Lung bud tissue between lungs and glottis become larynx, trachea and bronchi

Upper Respiratory System: Larynx

Functions to control entrance to trachea and to allow speech

Comprised of several cartilages…

Tracheotomy or Cricothyrotomy

What are the functions of the larynx?

Upper Respiratory System: Larynx

What are the functions of the larynx?

BI 203 Human Anatomy & Physiology II

http://www.ghorayeb.com/LARYNXPICTURES.html

Upper Respiratory System: LarynxWhat are the functions of the larynx?

Resonating chambers and snorkels

Since birds don’t have a larynx… how do they make noise?

They pass air through a structure (syrinx) just cephalic to bronchi.

Upper Respiratory System: Larynx

Lower Respiratory System: Lungs

What special adaptations do birds have?

Lower Respiratory System: Lungs

Lower Respiratory System: LungsWhat special adaptations do birds have?

Lower Respiratory System: LungsWhat special adaptations do birds have?

Lower Respiratory System: Lungs

How do the components of alveoli differ?

http://medinfo.ufl.edu/year1/histo/quiz/mh09.html

* Macrophages

* Type I pneumocytes

* Type II pneumocytes

Lower Respiratory System: Lungs