With regard to the respiratory system and the process of respiration in man, answer the following questions:

(a) Name the two muscles that help in breathing.

(b) Briefly describe how the above mentioned muscles help in the inspiration of air.

(c) Give the overall chemical equation to represent the process of respiration in humans.

(d) What is meant by:

1. Residual air
2. Dead air space

Starting from the nostrils, trace the path in sequence which the transpired air takes until it reaches the air sacs.

What are the functions of the following in breathing?
Diaphragm

What are the functions of the following in breathing?
Abdominal muscles