Respiration Unit Flashcards
Four stages of respiration
- Breathing
- External respiration
- Internal respiration
- Cellular respiration
Breathing
Inspiration and expiration
External respiration
Exchange of gases between lungs and blood
Internal respiration
Exchange of gases between blood and cells
Cellular respiration
Energy releasing reactions in cells
Types of respiration surfaces
- Outer skin
- Gills
- Tracheal system
- Lungs
How many lobes does each lung have?
Right has 3. Left has 2.
Lung anatomy
The lungs lie within a sealed off thoracic cavity.
The rib cage encloses the thoracic cavity.
Intercostal muscles lie in between each rib.
One later of pleural membranes encloses the lungs, while a second lager adheres closely to the chest wall and diaphragm.
These two layers are separated by a thin film of fluid called intra pleural fluid.
Pleural membranes prevent friction between the rib cage and the lungs.
Tidal volume
Volume of air moved in and out with each normal breath
Inspiration reserve volume
Air taken in through forced inspiration
Expiratory reserve volume
Air expelled through forced expiration
Vital capacity
Tidal volume + expiratory reserve + inspiration reserve
Residual volume
Air remaining in lungs so they don’t collapse
Dead space
Areas where air is not used up for gas exchange
Negative feedback cycle
- Nerve impulses cause respiratory muscles to contract
- Lungs inflate
- Inflation of lungs stops the respiratory center from sending nerve impulses
- Muscles relax and deflate
- Nerve impulses are no longer stopped causing muscles to contract again
Change in inspiration
CO2 and H+ rise in blood
Receptor of inspiration
Chemoreceptors in carotid bodies in carotid artery and aortic bodies in sorts detect increased CO2 and H+ concentration and signal to medulla oblongata
Effector of inspiration
Medulla oblongata will stimulate diaphragm and intercostal muscles to contract by nerve impulse
Inspiration is
Active
Expiration is
Usually passive but can be active
Receptor of expiration
Inhaling expands the alveoli and stretch receptors in the lungs send inhibitory messages to the medulla oblongata
Control center of expiration
Medulla oblongata stops signalling diaphragm and intercostals
Effector of expiration
Diaphragm and intercostals relax
Our atmosphere is made up of molecules
O2 (21%) N2 (78%) CO2 (0.04%)