Ch. 22 Repiration Flashcards
What are the 2 factors for the type of respiratory structure?
1) Environment
2) Complexity
How do unicellular and simple multicellular respirate?
Diffusion b/c in contact with O2
- no specialized structure needed
What are 3 phases of gas exchange?
1) Breathing/General Respiration
2) Transport
3) Servicing of cells
Breathing / General Respiration
Inhalation and exhalation
Inhalation
Oxygen from external environment to inside
- muscles contract –> active
- increase volume, pressure decreases –> air flow in
Exhalation
CO2 from inside to out
- muscles relax –> passive
- volume decreases, pressure increases –> air expelled
Transport
Oxygen diffuses from respiratory to blood vessel, attach to hemoglobin and delivered to every cell
- CO2 opposite
Servicing of cells
Oxygen diffuse blood to cells and CO2 diffuse cell to blood
- oxygen is used in cellular respiration for release of ATP as it pulls electrons form organic compound to make H2O
Respiratory Surface
Site of gas exchange
What are the 3 characteristics for efficiency of respiratory surface?
1) Thin b/c diffusion needs small distance
2) Moist b/c gases must be dissolved in water for diffusion
3) Extensive surface area b/c meet the needs of every cell and dispose of CO2
4 types of respiratory organs
1) Skin
2) Gills
3) Tracheae
4) Lungs
Skin
Gas exchanged via skin as oxygen diffuses from the outside to the capillaries right underneath
- small, simple, long, thin, flat
- no specialized respiratory organ, use body
- invertebrate, water or moist soil, earthworm
Gill
Common for aquatic animals
- small amount of body but high surface area to volume
- surrounded by capillaries
- countercurrent exchange
What are 3 reasons why aquatic organisms struggle compared to terrestrial organisms?
- Less oxygen in water. (1% vs 21%)
- Diffusion of oxygen in water is 300x slower than air.
- Air is lighter than water so its easier to move across respiratory surfaces
Tracheae
System of small tubers that branch thru out body and subdivide for higher surface area to volume
- tracheoles carry oxygen directly to cells
- doesn’t use blood (less energy, smaller size)
- terrestrial arthropods
- no localized respiratory organs
Lungs
Respiratory organ in complex vertebrates (snail)
- site of oxygen in air in contact with blood, CO2 blood to air
- located in thoracic cavity
- bronchi, bronchioles, alveoli, capillaries
- blood
An internal sac, lined with moist epithelium, where gases are exchanged b/w air and the blood
Gas Exchange (respiration)
Gas exchange or breathing; the exchange of O2 and CO2 b/w an organism and its environment. An aerobic organism takes up O2 and gives off CO2.
- cellular respiration; the aerobic harvest of energy from food molecules by cells
Ventilation
A mechanism that provides contact b/w an animal’s respiratory surface and the air/water to which it is exposed. Contact b/w a respiratory surface and air/water enables gas exchange to occur
Countercurrent Exchange
The transfer of a substance from a fluid or volume of air moving in one direction to another fluid or volume of air moving in the opposite direction
- opposite flows maintain a diffusion gradient that enhances transfer of the substance
Tracheoles
The narrowest tube in an insect’s tracheal system
Diaphragm
The sheet of muscle separating the chest cavity from the abdominal cavity in mammals; its contractions expands the chest cavity, and its relaxation reduces it
What is the pathway that air travels?
- Nasal cavity
- Pharynx
- Larynx
- Trachea
- Bronchi
- Alveoli
- Lungs
Bronchioles
A thin breathing tube that branches from a bronchi within a tube
Pharynx
Digestive and respiratory tract (pathway for food/liquid and air)
- food enters pharynx ventral and exits dorsal
- air enters dorsally and exits ventral
- epiglottis
