Respiration

What features are necessary for any respiratory surface to work efficiently

Whether outside the body, or inside the lungs, all respiratory surfaces share 3 characteristics: 1. Suface area must be large in order to meet an animal's demand for O2 but also eliminate CO2 waste enough to keep the waste from going toxic. 2. The surface must come into contact with either air or water; both of these substances can be a source of O2 and a dumping ground for CO2. Air offers advantages over water (higher concentration of O2 and lighter than water) 3. Respiratory surfaces consists of moist membranes across which O2 and CO2 diffuse. Requirement for moisture puts air breathing organisms at a disadvantage since the surface may dry out, rendering it useless.

Describe completely the exchange of O2 and CO2 between the air in the alveolus and the blood in the surrounding capillaries. Be sure to include the basic requirements for diffusion in this explanation.

As we breathe, O2 from the atmosphere enters the capillaries surrounding the alveoli; CO2 moves in the opposite direction, from the capillaries to the alveoli. More specifically, CO2 diffuses out of red blood cells and plasma and into the alveoli of the lungs. O2 moves in the opposite direction. In the rest of the body, O2 diffuses from blood and to tissues, while CO2 moves into the bloodstream. Respiratory surfaces consist of moist membranes across which O2 and CO2 diffuse. Diffusion requires moisture.

Describe four types of respiratory surfaces and the types of animals that use them

1. Body Surface - Amphibians like frogs -Gases diffuse through the body's surface 2. Tracehae - Insects -Gases enter tracheae and diffuse directly into the cells (not through capillaries) 3. Gills - Fish -Gases are exchanged at blood vessel covered by a thin layer of epithelium 4. Lungs - Humans -Two way air flow

Describe the respiratory system of a human by tracing air all the way from the mouth and nose to the alveoli, naming all the structures along the way

Air enters through the nose where it is filtered by stiff hairs to keep out dust and large particles; epithelial tissue in the nose secrets a sticky mucus that catches most airborne bacteria. Air from the nose and mouth then goes to the pharynx, or throat. Food and air pass through the pharynx. The larynx is just below and in front of the pharynx, directing food and drink away from the respiratory system. The epiglottis covers the glottis so that food goes down the right pipe. The trachea, or windpipe, is the tube just beneath the larynx. Cilia and mucus coat the trachea's inside surface, trapping debris and moistening the air. The trachea branches into two bronchi, one leading to each lunch. The bronchi branch repeatedly. Bronchioles are the finest branches. Each bronchiole narrows into several alveolar ducts, and each duct opens into a grape like closer alveoli, where gas exchange occurs. or 1. O2 enters the mouth or nasal cavity 2. goes to pharynx 3. goes to larynx 4. goes to trachea 5. goes to bronchi 6. goes to bronchioles 7. goes to alveoli

Explain the mechanism of breathing (rib and diaphragm movements) during both inhalation and exhalation. Be specific when explaining the causes and effects. Also, in your answer explain how pressure and volume are related.

Breathing in: rib muscles and diaphragm contract When these contract, they expand your rib cage pressure (# of molecules/volume) decreases air from high pressure (atmosphere) rushes into low pressure (lungs)' Breathing out: 1) Rib muscles and diaphragm relax 2) when these relax, rib cage contracts (in size) 3) pressure increases 4) air from high pressure (lungs) rushes into low pressure (atmosphere)

Explain the connections between breathing, gas exchange, and cellular respiration

Breathing is the physical process by which air is passed on a gaseous exchange surface i.e. ventilation of the gaseous exchange surface. It involves Inhalation and Exhalation. Gas/Gaseous exchange is the process whereby gasses diffuse across a gaseous exchange surface. In humans, oxygen diffuses from the inhaled air into the blood and carbon dioxide diffuses from the blood into the exhaled air. The gaseous exchange surface here being the Alveoli. Respiration is the metabolic process whereby organic molecules are broken down to release energy in the cells. In humans, this process takes place inside the mitochondria of cells. Aerobic respiration requires oxygen whereas qnqerobic respiration takes place in absence of oxygen.