(10) Anatomy- Respiratory System (Gas Exchange)

What is the normal pH of blood?

7.4, slightly basic

How are carbon dioxide and bicarbonate ions transported through the blood?

a little bit remains dissolved in blood plasma; most of the carbon dioxide enters the red blood cell (some of it combines with hemoglobin, the rest is converted into bicarbonate ions, which return to the plasma)

What is the diaphragm?

a sheet of muscle that separates the chest cavity and the abdominal cavity

What happens in the alveoli?

air comes from the bronchioles. The alveoli form the collective respiratory surface where gas exchange takes place. The alveoli lie adjacent to a dense network of capillaries. Gas exchange occurs across alveolar membranes, with oxygen diffusing from alveoli to capillaries, and carbon dioxide diffusing in the opposite direction. Carbon dioxide is exhaled out, while oxygen is carried to body tissues, where it diffuses out of the capillaries and into cells.

What happens in the nasal cavity and oral cavity?

air enters, where it is moistened, warmed, and filtered. Air is passed to the pharynx

What is negative pressure breathing?

air is pulled into the lungs from the inside because air flows from areas of higher pressure to areas of lower pressure

What happens in the larynx?

air passes there from the pharynx. The larynx also contains vocal chords, elastic bands of muscle. Air enters into the trachea

What happens in the trachea?

air passes through there from the larynx. The trachea is held open by rings made of cartilage. The trachea branches into the left and right bronchi

Where are the lungs located?

chest cavity

What is the breathing control center of the brain?

medulla oblongata, or also known as the brain stem

How does the medulla oblongata work?

monitors carbon dioxide levels and pH in the blood. When carbon dioxide levels increase, and when pH decreases, sends nerve impulses to the diaphragm to rib muscles, increasing breathing rate

How are oxygen and hemoglobin transported through the blood?

oxygen is carried in the red blood cells by hemoglobin

What happens in the pharynx?

the air is passed there from the nose and mouth. Air enters the larynx next.

What happens in the bronchi?

the bronchi are branches of the trachea. Each bronchus enters a lung and branches into smaller bronchioles. Each bronchiole terminates in alveoli.

What happens during inhalation?

the diaphragm contracts and moves down. Ribcage expands. Volume of the chest cavity increases, which lowers air pressure. Negative pressure breathing occurs

What happens during exhalation?

the diaphragm relaxes and moves up. The ribcage gets smaller. Air pressure in lungs increases, forcing air out

Why are respiratory passages lined with mucus and cilia?

the mucus is a cleaning system

What is the concept of a respiratory surface?

the surfaces must be kept constantly moist and are usually only one cell thick; allows for rapid diffusion of gases involved

What is gas exchange?

the uptake of oxygen from the environment and release of carbon dioxide to the environment

What is breathing?

the ventilation of the lungs