The Respiratory System

Gaining oxygen from the environment while riding the body

of water and carbon dioxide

Breathing vs. Respiration

• Breathing is the movement of air into and out of the lungs.

• Respiration is the releasing of energy through chemical reactions that act on oxygen and glucose inside cells.

Nose

• The nose is where air enters into the nostrils. The nose is lined with cilia and mucus.

Cilia• Cilia traps particles of dirt and dust from

the air. The cilia filters the air we breathe.

Mucus• Mucus warms and moistens the air that

enters the body. Mucus is present in the nasal cavity and other locations throughout the body.

Pharynx

• Another term for the throat, which is the passageway that air enters through the nose.

• Food also enters via the pharynx.

Trachea

• A tube made of cartilage that leads from the pharynx toward the lungs.

Cartilage Rings

• Rings around the trachea that strengthen the trachea and keep it open.

Bronchi• Branches that lead from the trachea into the

lungs. Bronchi passageways get smaller and smaller until they reach the alveoli. The right and left bronchi lead to each lung; part of them are inside and part are outside of the lungs.

Alveoli

• Alveoli are tiny sacs of lung tissue that allow oxygen to pass into the blood and carbon dioxide to pass out of the blood.

Lungs

• The main organs of the respiratory system. Inside the lungs are passageways called bronchi which direct air into the lungs.

Diaphragm

• The diaphragm is a large arched muscle that moves downward when inhaling to allow more air in, and moves upward when exhaling to push more air out.

Epiglottis• The epiglottis is a flap of tissue that seals

off the windpipe to prevent food from entering into the airways.

Larynx

• The larynx is the voce box of the body; it is located in the top of the trachea under the epiglottis.

Vocal Chords

• The vocal chords are folds of connective tissue that stretch across the larynx (voice box) to produce a person’s voice.