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.
After pollination and fertilization following changes occur in a flower: (i) The petals, stamens, style and stigma of the flower fall off. (ii) Sepals dry up and hold the ovary. (iii) The ovules confined in the ovary develop into seeds.
Mitochondrial DNA mutation occurs at a constant rate throughout history. Thus, each different base in Mitochondrial DNA is able to show just how long ago the 2 species diverged from each other. Hope this helps! :)
The process of diffuse transports the substances in the direction of their concentration gradients. Diffusion of substance from the region of their higher to that of the lower concentration does not require any energy. Being a passive process, diffusion can be carried out by a cell irrespective of the status of its ATP supply. Therefore, an animal cell containing a small amount of cyanide can transport substances by diffusion.
