Introducing 

Prezi AI.

Your new presentation assistant.

Refine, enhance, and tailor your content, source relevant images, and edit visuals quicker than ever before.

Loading…
Transcript

Evolution of the Respiratory System

Amy

Angela

Bhuvana

Blaire

About the Respiratory System

  • The respiratory system exchanges oxygen and carbon dioxide between the external environment and the internal environment.
  • Small animals have a high surface area to volume ratio allowing them to meet all their metabolic gas needs by diffusion through the skin.
  • Large animals must transport gases between the internal tissues and a diffusion surface exposed to the external medium (water or air).

A respiratory system needs three things:

  • A large respiratory surface area (gills or lungs)
  • A method for ventilating the respiratory surface
  • A pump and circulatory system (heart and blood vessels) to distribute the gases

Invertebrates

  • The simplest and most ancestral respiratory surface is the skin.
  • This is true for small pre-vertebrates that have no specialized gas exchange surface
  • Mollusks generally have gills that allow exchange of oxygen from an aqueous environment into the circulatory system
  • Respiratory system is similar to that of vertebrate fish
  • Insects use a series of external openings called spiracles
  • These external openings, which act as muscular valves in some insects, lead to the internal respiratory system, a densely networked array of tubes called trachea

Fish

  • In most fish respiration takes place through gills
  • Fish breathe by gulping water through the mouth and discharging it through the gill chamber
  • Lungfish, however, do possess one or two lungs.
  • The labyrinth fish have developed a special organ that allows them to take advantage of the oxygen of the air, but is not a true lung.

Amphibians

  • Amphibians derive up to 100% of their gas exchange through cutaneous respiration
  • Both the lungs and the skin serve as respiratory organs in amphibians
  • The skin is highly vascularized and moist, with moisture maintained via secretion of mucus from specialized cells
  • Lungs are of primary importance to breathing control but, the skin's unique properties aid in rapid gas exchange when amphibians are submerged in oxygen-rich water.

Birds

  • Birds breathe using a respiratory system that consists of a pair of lungs and a number of separate air sacs
  • Most birds have nine air sacs, which are connected to the lungs in such a way that when a bird breathes air it is first drawn into the posterior air sacs.  
  • It then flows though the lungs in a single direction into the anterior air sacs through a fine set of 'air capillaries' (the parabronchi) in the lung.  
  • The air capillaries are closely surrounded by blood capillaries and this is where the exchange of oxygen and carbon dioxide takes place.  
  • The air sacs and lungs are arranged in such a way that air flows in the same direction through the lungs whether the bird is inhaling or exhaling (uni-directional flow-through).  
  • Unlike mammals and other tetrapods, the avian lungs remain the same volume during breathing - the air is pumped by changes in the volume of the air sacs not the lungs.
  • The bird skeleton is highly pneumatized - that means that there are large air spaces in the bones and vertebrae of birds which connect with the air sacs.

Theropod dinosaurs have vertebrae pneumatized in a way that is very similar to modern birds.

Evolution Similarities

  • The cervical air sac connect to vertebrae and ribs in the neck region of the spine, and in the thoracic vertebrae nearest the head
  • The abdominal air sac connects with the tail and sacrum vertebrae and the thoracic vertebrae nearest the tail
  • The lung itself connects with the mid-thoracic vertebrae.
  • This situation is consistent for all known non-avian theropods, suggesting that it is a derived characteristic of the first theropods and spread throughout the entire clad of theropods including modern birds

Reptiles

  • In squamates the lungs are ventilated almost exclusively by the axial musculature. This is also the same musculature that is used druing locomotion and because of this most of these reptiles are forced to hold their breath during intense runs.
  • Varanids, and a few other lizard species, employ buccal pumping. This allows the animals to completely fill their lungs during intense locomotion, and thus remain aerobically active for a long time
  • Reptiles evolved from amphibians during the Carboniferous.
  • Unimodal water breathing-> Bimodal Air breathing -> unimodal air breathing
  • Changes occurred in the gas exchange organ and its mode of ventilation
  • The amount of gills decreased
  • lungs inflated by expansion of the rib cage

Mammals

What Respiration Does For Mammals

Respiration is necessary to extract oxygen from the air, which is used by cells. Respiration also carries waste carbon dioxide away from the cells. Although respiration depends on other systems (like the circulatory system) to take oxygen and carbon dioxide to and from cells, the respiratory system is primarily responsible for bringing oxygen in to a mammal's body and sending carbon dioxide into the atmosphere.

Muscle Structures

Mammalian respiratory systems rely on a single large muscle at the base of the lungs called a diaphragm

The diaphragm pulls the lungs downward to increase their volume, causing air to rush into the lungs

As it presses upward, the lungs become smaller, and air is exhaled

Muscles in the rib cage work in consort with the diaphragm to expand and contract the lungs.

Airways

Different mammals breathe differently

Some breathe through the nose, others breathe through the mouth (some mammals are able to breathe through either the nose or the mouth)

As the air passes through the nose or down the trachea, or airway, small hairs and microscopic hair-like structures filter the air by attracting dust and microbes that could cause damage or infection in the lungs

Lung Structures

As the air passes through the airways, it enters the lungs

Mammals have two lungs

The air is split between the lungs by an airway called bronchi and moves to smaller airways called bronchioles. The bronchioles take the air to alveoli, which are small sacs where the gas transfer occurs.

Problems With Mammilan Respiration

Mammalian respiration can be interrupted by the presence of liquid in the lungs

Whether from an infection or artificially introduced, such as in the case of drowning, liquid in the lungs interferes with the gas transfer in the alveoli. As the alveoli fill with water, less oxygen can reach the blood cells. In extreme cases, such as drowning, enough oxygen is blocked that the brain of the mammal dies.

Humans

The respiratory system is made up of the organs involved in breathing and consists of the:

  • nose
  • pharynx
  • larynx
  • trachea
  • bronchi
  • lungs

The upper respiratory tract includes the:

  • nose
  • nasal cavity
  • ethmoidal air cells
  • frontal sinuses
  • maxillary sinus
  • larynx
  • trachea

The lower respiratory tract includes the:

  • lungs
  • bronchi
  • alveoli

The Pathway

  • Air enters the nostrils
  • Passes through the nasopharynx,
  • The oral pharynx
  • Through the glottis
  • Into the trachea
  • Into the right and left bronchi, which branches and re-branches into bronchioles, each of which terminates in a cluster of alveoli

Respiratory Diseases

Inflammatory lung disease - Characterised by a high neutrophil count

Ex. Asthma, cystic fibrosis, emphysema, or acute respiratory distress syndrome

Obstructive lung diseases - Obstructive lung diseases are diseases of the lung where the bronchial tubes become narrowed making it hard to move air in and especially out of the lung.

Ex. Chronic Obstructive Pulmonary Disease (COPD), an example of an obstructive lung disease, is where the airways become damaged, causing them to narrow.

Restrictive lung diseases (also known as interstitial lung diseases) - are a category of respiratory disease characterized by a loss of lung compliance, causing incomplete lung expansion and increased lung stiffness.

Ex. Infant Respiratory Distress Syndrome (IRDS)

Respiratory tract infections - Infections can affect any part of the respiratory system. They are traditionally divided into upper respiratory tract infections and lower respiratory tract infections.

Upper respiratory tract infection - The most common upper respiratory tract infection is the common cold. However, infections of specific organs of the upper respiratory tract such as sinusitis, tonsillitis, otitis media, pharyngitis and laryngitis are also considered upper respiratory tract infections.

Lower respiratory tract infection - The most common lower respiratory tract infection in is pneumonia, a lung infection. Pneumonia is usually caused by bacteria, particularly Streptococcus pneumoniae in Western countries. Worldwide, tuberculosis is an important cause of pneumonia. Other pathogens such as viruses and fungi can cause pneumonia for example severe acute respiratory syndrome and pneumocystis pneumonia. A pneumonia may develop complications such as a lung abscess, a round cavity in the lung caused by the infection, or may spread to the pleural cavity.

Other Taxonomic Groups

Process of Respiration in Plants

Breathing

Many of us know that people breathe in oxygen and breathe out carbon dioxide, and plants breathe in carbon dioxide and breath out oxygen. But that's not the whole picture. Plants also take in oxygen and release carbon dioxide. Timing is the main issue in determining what is happening within the plant. It really depends on the time of day and sun exposure.

Gas Absorption

By gases being absorbed through pores in the plant: With the absorption of gases through the pores, oxygen is taken in and reacts with glucose. The plant then releases carbon dioxide. The pores of the plant are located everywhere, even the roots. For this reason it is best not to give a plant too much water. It blocks the absorption process, and the plant literally drowns.

Photosynthesis

With photosynthesis, plants absorb light and carbon dioxide. They breathe out oxygen. The sunlight helps break down water and carbon dioxide within the plant and reforms it into oxygen and glucose. Oxygen is then released into the air.

Timing of Each Process

Timing affects what a plant produces. At night there is no way for photosynthesis to occur for most plants, so the plant only gives off carbon dioxide. During cloudy days or low light, the two processes are about even, and they cancel each other out. But during sunny days, plants give off more oxygen than carbon dioxide.

Bacteria

Bacterial respiration is the extraction of energy from glucose to convert that energy into forms the bacteria can use

Free Oxygen

Using free oxygen, bacteria can fully exploit all three chemical pathways for energy extraction--glycolysis, the Krebs Cycle and the electron transport chain

Oxygen Compounds

In the absence of oxygen, some bacteria can still use oxygen by getting it from inorganic oxygen-containing molecules, such as nitrate, nitrite and sulfate

No Oxygen

Alternatively, fermentation enables some bacteria to derive energy from glucose without using oxygen of any kind

Comparisons

Respiration using oxygen (aerobic respiration) provides bacteria with as much as 19 times more energy per glucose molecule than does fermentation, notes the book "Biology." Generally, the more of the electron transport chain respiration uses, the more energy it provides

Respiration in Fungi and Protists

Accomplished by direct diffusion. In direct diffusion, oxygen passes from the environment through cells on the animal's surface and then into individual cells inside. Sponges, jellyfish, and terrestrial flatworms use this primitive method of respiration. These animals do not have special respiratory organs. Microbes, fungi, and plants all obtain the oxygen they use for cellular respiration by direct diffusion through their surfaces.

Many fungi are capable of burning sugars just like animals, using oxygen and producing carbon dioxide and water as waste products. Obviously they don't have lungs and complex circulatory systems, but the chemistry is the same.

Also like animals, some fungi are capable of anaerobic "respiration" without atmospheric oxygen. Carbon dioxide is still produced, but also other more complex waste products. While these waste products are toxic in animals and limit the use of anaerobic metabolism, in fungi they can be beneficial.

Bibliography

"Anatomy of the Respiratory System." University of Maryland Medical Center | Home. Web. 20 Mar. 2011. <http://www.umm.edu/respiratory/anatomy.htm>.

"Bird Lung." Alec's Evolution Pages with Scientific Evidence for Evolution and Refutations of Creationist Arguments. Web. 20 Mar. 2011. <http://www.evolutionpages.com/bird_lung.htm>.

Jie, Ma Wen. "Respiration in Mammals | EHow.com." EHow | How To Do Just About Everything! | How To Videos & Articles | EHow.com. Web. 21 Mar. 2011. <http://www.ehow.com/about_7220116_respiration-mammals.html>.

"List Of Respiratory Diseases." Cape Town Doctors. Web. 20 Mar. 2011. <http://doctors-hospitals-medical-cape-town-south-africa.blaauwberg.net/details.php?id=831>.

"Respiratory System: Chapter 24." Wikipedia. Web. 21 Mar. 2011. <http://en.wikipedia.org/wiki/Respiratory_system>.

"Transition from Reptiles to Birds: Creationism Point of View." Science Forums. Web. 20 Mar. 2011. <http://www.scienceforums.net/topic/13277-transition-from-reptiles-to-birds-creationism-point-of-view/>.

Winsenden, Brian. "Respiratory System: Chapter 24." Web. 19 Mar. 2011. <http://cwx.prenhall.com/bookbind/pubbooks/martini10/chapter24/custom2/deluxe-content.html>.

Ladybug

Mollusk

Clownfish

Lungfish

Blue Poison

Dart Frog

Red-eyed

Tree Frog

African

Bullfrog

Learn more about creating dynamic, engaging presentations with Prezi