Factors that cause a decrease or increase in energy demand directly affect rate of breathing.
- Exercise, any muscular activity like digging.
- Sickness
- Emotions like anger, flight
Effects of Exercise on Rate of Breathing
- Students to work in pairs.
- One student stands still while the other counts (his/her) the number of breaths per minute.
- The student whose breath has been taken runs on the sport vigorously for 10 minutes.
- At the end of 10 minutes the number of breaths per minute is immediately counted and recorded.
- It is noticed that the rate of breathing is much higher after exercise than at rest.
Dissection of a Small Mammal (Rabbit) to Show Respiratory Organs
- The rabbit is placed in a bucket containing cotton wool which has been soaked in chloroform.
- The bucket is covered tightly with a lid.
- The dead rabbit is placed on the dissecting board ventral side upwards.
- Pin the rabbit to the dissecting board by the legs.
- Dissect the rabbit to expose the respiratory organs.
- Ensure that you note the following features.
- Ribs, intercostal muscles, diaphragm, lungs, bronchi, trachea, pleural membranes, thoracic cavity.