External environment CO2 O Food 2 Mouth Animal
Respiratory system
Digestive system
Interstitial fluid
Heart
Nutrients
Circulatory system Body cells Urinary system
Intestine
Anus Unabsorbed matter (feces)
Metabolic waste products (urine)
Respiratory System
LO’s:
Explain gas exchange across respiratory surfaces Understand and describe the pathway of respiratory system
Single-celled organisms/unisel : exchange gases directly across their cell membrane. Problem: the slow diffusion rate of oxygen relative to carbon dioxide limits the size of single-celled organisms.
Simple animals that lack specialized exchange surfaces have flattened, tubular, or thin shaped body plans, which are the most efficient for gas exchange. However, these simple animals are rather small in size. Large animals cannot maintain gas exchange by diffusion across their outer surface. They developed a variety of respiratory surfaces that all increase the surface area for exchange, thus allowing for larger bodies A respiratory surface is covered with thin, moist epithelial cells that allow oxygen and carbon dioxide to exchange. Those gases can only cross cell membranes when they are dissolved in water or an aqueous solution, thus respiratory surfaces must be moist.
The right lung is slightly larger than the left. The highest recorded "sneeze speed" is 165 km per hour. The surface area of the lungs is roughly the same size as a tennis court.
The breathing rate is faster in children and women than in men.
The capillaries in the lungs would extend 1,600 kilometers if placed end to end.
Respiratory System- The group of organs in your body that are responsible for taking in Oxygen and breathing out the Carbon Dioxide which is the waste product of cellular respiration. The main function of Respiratory System: - Supplies the blood with O2 – deliver to all parts of the body - Removes CO2 waste that cells produces
‘supply the blood with oxygen in order for the blood to deliver oxygen to all parts of the body’
Functions • Gas Exchange: oyxgen into the lungs and carbon dioxide out • Work with Circulatory System: transport gases through the body and back to the lungs
Flatworms and annelids use their outer surfaces as gas exchange surfaces
Amphibians use their skin as a respiratory surface -lamellae
Gills greatly increase the surface area for gas exchange.
Tracheal Systems Many terrestrial animals have their respiratory surfaces inside the body and connected to the outside by a series of tubes. Tracheae are these tubes that carry air directly to cells for gas exchange. Spiracles are openings at the body surface that lead to tracheae that branch into smaller tubes known as tracheoles.
Humans cannot survive for more than a few minutes witout O2. WHY? Cells requires O2 celular respiration --- enough ATP
Human Respiratory System
Lower Respiratory Tract
Functions: Larynx: maintains an open airway, routes food and air appropriately, assists in sound production Trachea: transports air to and from lungs Bronchi: branch into lungs Lungs: transport air to alveoli for gas exchange
Respiratory Cycle
Figure 10.9
The diaphragm 1. The function: to help pump the carbon dioxide out of the lungs and pull the oxygen into the lungs. 2. contracts and relaxes, breathing takes place 3. contracts, oxygen is pulled into the lungs 4. When the diaphragm relaxes, carbon dioxide is pumped out of the lungs.
Gas Exchange Between the Blood and Alveoli
Figure 10.8A
Air enters the body through the nose, is warmed, filtered, and passed through the nasal cavity. Air passes the pharynx (which has the epiglottis that prevents food from entering the trachea).The upper part of the trachea contains the larynx. The vocal cords are two bands of tissue that extend across the opening of the larynx. After passing the larynx, the air moves into the bronchi that carry air in and out of the lungs.
Ventilation is the mechanics of breathing in and out. When you inhale, muscles in the chest wall contract, lifting the ribs and pulling them, outward.
Ventilation: The mechanics of breathing in and out through the use of the diaphragm and muscles in the wall of the thoracic cavity.
As altitude increases, atmospheric pressure decreases. Above 10,000 feet decreased oxygen pressures causes loading of oxygen into hemoglobin to drop off, leading to lowered oxygen levels in the blood. The result can be mountain sickness (nausea and loss of appetite). Mountain sickness does not result from oxygen starvation but rather from the loss of carbon dioxide due to increased breathing in order to obtain more oxygen.
