Answer:
1. Nucleus
2. Nuclear DNA
3. Chromosomes. They contain the DNA.
4. This is DNA. DNA contains the instructions needed for an organism to develop, survive and reproduce.
The muscles that are grouped in between the ribs are called Intercostal
Simple....
as you've learned... cells create tissue..tissue creates organs...organs create organ systems..and organ systems create organisms. They all work together to create something...
An example:
muscle cell-->>muscle tissue-->>heart-->>circulatory system-->>the circulatory system makes up a part of the body.
Thus, your answer.
The events of inspiration begins with the;
Impulses are conducted on the phrenic nerve to muscle fibers in the diaphragm contracting them.
As the dome shaped diaphragm moves downward the thoracic cavity expands.
At the same time the external intercostal muscles may contract raising the ribs and expanding the thoracic cavity further.
The intra-alveolar pressure decreases
Atmospheric pressure greater than intra-alveolar pressure forces the air into the respiratory tract through the air passages.
The lungs fill with air.
