Post on 06-May-2015
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RESPIRATORY SYSTEMRamyr Delos Reyes
Allyson Nicole ManaloClaudine P. Naz
Janyka Angela B. RomanKristel G. Zamora
Respiratory system -is a system consisting of specific organs and structures used for the process of respiration in an organism.
General FunctionRespiration-the act or process of inhaling or
exhalingRespiration includes:- Ventilation is the pumping of water in gills and
of air in lungs -External Respiration- exchange of gases with
the environment-Internal Respiration- essential gases are then
exchange with the tissues in the respective capillary beds
Respiratory Organs
GILLS Vertebrate gills are designed for
water breathing Mechanism of ventilation depends
on whether the gills are located internally or externally
1. INTERNAL GILLS2. EXTERNAL GILLS
LUNGS Designed for air breathing Elastic bags that lie within the body Volume expands when air is inhaled
and decreases when air is exhaled
GAS BLADDERS Are air filled with the air Swim bladders are used to control
the buoyancy of a fish
Gas bladders differ in lungs in two ways1. Gas bladders are usually situated dorsal
to the digestive tracts2. Gas bladders are not paired
Oxygen is released into the bladder Gas in the swim bladder is mainly oxygen
CUTANEOUS RESPIRATION Respiration through the skin Amphibians rely heavily in cutaneous
respiration
BREATHING EMBRYOS Chorioallantois in birds acts as respiratory
organs in birds It sustains the respiratory needs of the
chicken embryo for most of its time in the egg
VENTILATORY MECHANISM CILIA lines the routes along which water
current flows
MUSCULAR MECHANISM Ventilation on vertebrates usually
depends much on muscle action Ram ventilation is a technique by which
the fish’s own forward locomotion contributes to gill ventilation
1. Water Ventilation: Dual pump2. Air ventilation: Pulse pump3. Air ventilation: Aspiration pump
Air Ventilation: Pulse pump
FISHESRespiration: Gills or swim
bladder Gills External Gills-develop from surface
ectoderm and extend beyond the head Internal Gills- lie within the head Comprised of gill arches with gill
filamentslined with rows of lamellae (increase surface area)
Utilize countercurrent exchange(except for cartilaginous fishes)
blood flows oppposite to the direction of water movementg against gills
INTERNAL GILLS- develop from the pharynx as evaginations
called pharyngeal pouches Visceral grooves (opposite to the pouches) Closing plates (separates pouches and
grooves)
- The general structure of a mature gill is composed of several parts: Gill bars (support the gills) Gill rakers (prevents food particles from
entering) Gill rays Gill filaments and Gill lamellae
3 TYPES OF GILL BARS Holobranch Hemibranch Pseudobranch
AGNATHAN Pouched gills 6-15 pairs of gill pouches No gill Slits Hagfishes and lampreys
Cartilaginous fishes Septal Gills 5 “naked” gill slits Shark and rays
Bony Fihes Opercular gills (operculum) 5 gill slits Eels, salmon and milk fish
SWIM BLADDERS
Gas or swim bladders of fishes may be located high in the cavity to remain upright
1. Physostomous Function for respiration
2. Physoclitous Do not function for respiration
Serves as an hydrostatic organ Oxygen and carbon dioxide are
exchanged between the bladder and the blood
Also important in hearing and sound production
Amphibians
AMPHIBIANS They are cold blooded, meaning they
don’t need much oxygen 2 simple sacs
Lungs - don’t have diaphragms and they force
air into their lungs by moving their mouth (like swallowing) Buccal pumping
Four stages of lung ventilation1.) Buccal cavity expands to draw fresh air
in through the open nares2.) Glottis opens rapidly, releasing spent air
from the elastic lungs3.( Nares close, floor the buccal cavity rises
forcing the fresh air held in this cavity into the lung through the open glottis
4.) Glottis closes, retaining the air that has just filled the lungs and nares open again
Skin- Highly vascularized and moist- Very thin nd allows water to go through it- Aquatic Amphibians and anurans
Cutaneous respiration- The short trachea divides into 2 short
bronchi leading to the apex of each lung- The opening from the trachea to pharynx is
called the glottis supported by the larynx
Gills ( aquatic salamanders and tadpoles)- Made up of very thin blood vessels
surrounded by water channe;s- When amphibians undergo
metamorphosis into adult, gills are lost
Reptiles
REPTILES
-Lungs are large and varied
-Rely largely on LUNGS for gas exchange
-Have large lung volumes (10xmore volume
compared to mammals)
-Trachea and bronchi are larger than for amphibians and are supported by cartilaginous rings
-Supplemental cutaneous respiration is significant, but for the most part, paired lungs meet their respiratory needs
-Filling of the lungs in all the reptiles is based on an aspiration pump
- Exhalation of passive
CROCODALIANS- Use diaphragm muscle for lung
ventilation
-Contraction of the diaphragmatic muscles draws the liver back, increasing the volume of the lung cavity and dropping pressure within the lungs
- In caimans and other crocodiles, ribs rotate forward and outward, expanding the cavity around the lungs during inhalation
SQUAMATES (Snakes and Lizards )-Don’t have diaphragm muscles for lung
ventilation
-The muscle s used for locomotion are the same used for their respiratory systems
-Contracting and flexing body muscles move their ribs and lungs
In most snakes , there are usually two regions of the lung:
1. Anterior respiratory portion or faveoli2. Posterior saccular portion or avascular -Submergence in water- have large lungs
for large amount of oxygen for long dives (Hydrophinae and Arochordidae)
TESTUDINES (Turtles)-Having shells makes lung expansion more
difficult-Must use their limbs for lung ventilation
expels air from the lungs and pushing their limbs out of their shells expands the lungs
-Have complex lungs w/ large surface areas and volumes
Mammals
4.) Mammals- The chief organ in mammalian respiration is the lungs (located in the pleural cavities in the thorax)- More finely, homogenously divided and
more efficient- Aspiration pumps ventilates the lungs of
mammals- Breathing is dependent to the rib muscles
and diaphragm
SUCTION-PUMP MECAHNISM OF INHALATION AND EXHALATION
inhalationwhen the rib cage opens up and the diaphragm flattens and moves downward; air rush inside
lungs expandsdecrease in air pressure exhalation the diaphragm and rib
muscles relax to their neutral state that causes the lungs to contract; air flow out
squashing of lungs increase in air pressure
AIR FLOW IS BIODIRECTIONAL: Trachea primary bronchi
secondary bronchi tertiary bronchi alveoli
Trachea is a long structure of soft tissue; supported by rings of hyaline or fibrous cartilages; elastic connective tissue joins the ring and completes the tube where cartilage is absent Splits into two bronchi branches, each enters its
lung anterior and dorsal to the center Divides into numerous membranous bronchioles Alveolus- tiny air sacs; increase surface area;
where actual gas exchange occurs
The trachea, bronchi and bronchioles that transport gas to and from the alveoli is called the respiratory tree
No gas exchange occurs along the conducting passageway of the respiratory tree until air reaches the alveoli Epiglottis Glottis
Birds
5.) Birds- Have one way flow of air in their lungs-Lungs are small but compact, rigid and have a fixed volume-Have two lungs connected to trachea and ventilated by an aspiration pump-Birds have air sacs that collect air and then force the air through their lungs-Large air sacs joined the lungs and serve to ventilate them in crosscurrent circulation-Gas exchange in the blood actually occurs in the air capillaries-Bones contain air, not marrow
-Lungs receive fresh air during inhalation and exhalation-Air is pulled by a suction type pull and gas exchange are in the capillaries-Trachea is divided into two primary bronchi, termed mesobronchi, that do not enter the lung but extend posteriorly to reach the posterior air sacs-Gases diffuse between the lumen of the parabronchus and the connecting, blind-ended air capillaries
-Oxygen diffuses in turn from the air capillaries into the adjacent blood capillaries that give up carbon dioxide to the air capillaries-Walls of air and blood capillaries constitute the site of gas exchange-Air sacs function to lighten the birds like helium balloon, but air sacs provide no lift, and it is not the prerequisite for flight
When bird inhales, air is brought into the posterior air sacs, which expand. Upon exhalation, air is forced from the posterior sacs into the lungs; second inhalation will move the air from the lungs to the anterior air sac and second exhalation will push the air out
Advantages of one-way flow:1.)No residual volume; all old air leaves w/ each breath2.)Cross-current blood flow through the lungs
Pattern of Gas Transfer- Respiratory organ couples blood flow with ventilation
Rates of Gas transfer- Respiratory organs must also be designed to match the ventilation rate with perfusion rate- Breathing that is too fast or too slow is inefficient- Ratio of perfusion to ventilation depends on the species
Breathing in Water- Water is considerably denser than air
FISHES
Cartilaginous Fishes
Bony Fishes(Teleost)
Agnathans
Septal Gills Opercular Gills Pouched Gills
5 “naked” gill slits Usually have 5 gill slits
6 to 15 pairs of gill pouches
Sharks and Rays Eels, milkfish, salmon Hagfishes and Lampreys
Reptiles Amphibians Birds Mammals
No vocal cords Simple saclike lungs Most of the birds has nine sacs and these
are: anterior and posterior sacs
Human breathe through lungs
No True Diahragms Some amphibians have no lungs like
Salamander
The typical bird trachea is 2.7 times
longer and 1.29 wider than that of
similarly-sized animals.
Alveoli- spongy and has a little sac
Reptile lungs composed of three
and these are: Unicameral,
Multicameral and Paucicameral
Skin- Cutaneous Respiration
Avian lungs Trachea
Reptiles are capable of surviving for long
periods without breathing.
Many amphibians used gills at least
when they are young.
Bronchi- structure similar to trachea, flexible tubes with stiffening walls of hyaline cartilage
Bronchioles
BIRD FISH MAMMAL REPTILE AMPHIBIAN
•Unidirectional•Lungs•Aspiration pump•Longer and wider trachea compared to mammals•Air sacs
•Unidirectional•Gills•Dual pump•5 to 7 pairs of gills
•Bidirectional•Lungs•Aspiration pump•Muscles are used•Air are filtered
•Bidirectional•Lungs•Aspiration pump•Much larger lungs than mammals•Can survive for long periods without breathing•Muscles are used
•Bidirectional•Lungs and skin•Pulse pump•Simple saclike lungs