Bone in the upper arm. called humerus
Proteins are organic compounds that consist of carbon, hydrogen, oxygen, nitrogen, and, in some cases, sulfur. They are made up of repeating units called amino acids. They provide cells with energy, form tissues, speed up chemical reactions throughout the body, and perform many other cellular functions.
During inhalation, you breathe in and this contracts the diaphragm and moves downwards. This increments the chest cavity space which means the lungs are expanding. The intercostal muscles or the muscles in between the ribs also aids in the enlargement of the chest cavity. Both muscles contract to pull your rib cage upward and outward when you inhale. As your lungs expand, air is sucked through your nose and mouth. It then travels down to the windpipe and into the lungs to the bronchus, bronchioles and eventually in the alveoli where air exchange between carbon dioxide and oxygen happens.
The additional accessory muscles of respiration are typically used only under conditions that are of high metabolic demand or respiratory dysfunction. However, in instances where these muscles become stiff and hard, expansion of the rib cage can be quite restricted. The accessory muscles of respiration include sternocleidomastoid and the scalene muscles namely anterior, middle and posterior scalene. Both aid in elevating the rib cage. However, their involvement seems to depend on the degree of respiratory effort. During quiet breathing, the scalenes are consistently active at certain phases while the sternocleidomastoid is quite.
As the gills does not develop into gills, they are likely to
contribute to the development of the lower jaw of the human embryo though after
the embryonic stage, the gill slits won’t be retained or won’t be a part of a
human as they only appear during embryonic stage for the development of the
lower jaw.
Acute stress comes with a lot of adrenalin and for most people living ordinary lives lacks that. -hope this helps have an amazing day!!