Human Respiration and Oxygen

Breathing Process

• When taking a deep breath, air enters through the mouth or nose and follows an identical path, meeting in the back of the throat.
• The air then travels down towards the Adam's apple (voice box), which helps control the voice and allows for changes in pitch.

Adam's Apple (Voice Box)

• The Adam's apple is a structure in the middle of the throat that everyone has, not just men.
• It's located in a notch in the throat and helps control the voice, allowing for changes in pitch.

Trachea and Lungs

• Air passes through the trachea and enters the lung area, which is divided into the right and left lungs.
• The right lung has three lobes (upper, middle, and lower), while the left lung has two lobes.
• The left lung has a cardiac notch due to the heart's presence during development.

Heart and Diaphragm

• The heart is located in the middle, surrounded by the lungs, and takes up space in the left lung.
• The diaphragm muscle makes up the floor of the thorax (chest cavity), while the ribs make up the walls.

Bronchial Tree

• The lungs have a tree-like structure, with air passing through the trachea and branching into smaller tubes.
• The bronchial tree has a main trunk (trachea) that splits into smaller branches, serving different lobes of the lungs.

Alveoli and Gas Exchange

• Air reaches the alveoli, microscopic sacs where gas exchange occurs.
• Oxygen from the air enters the blood, and carbon dioxide waste is released from the blood into the alveoli.
• The oxygen-rich blood then transports oxygen to the body's cells, while the carbon dioxide is exhaled out of the body.