Respiration Anatomy PDF

External Respiration The exchange of oxygen and carbon dioxide between the air and blood in the lungs. During external respiration, oxygen is inhaled into the air spaces, or sacs of the lungs and immediately passes into the tiny blood vessels surrounding the sacs. Internal (Cellular) Respiration...

External Respiration The exchange of oxygen and carbon dioxide between the air and blood in the lungs. During external respiration, oxygen is inhaled into the air spaces, or sacs of the lungs and immediately passes into the tiny blood vessels surrounding the sacs. Internal (Cellular) Respiration The exchange of gases between the bloodstream and the tissue cells. Internal respiration, on the other hand, is an exchange of gases at the cellular level within all organs. Oxygen passes out of the capillaries and into the tissue cells. Functions Cells use glucose (sugar) and oxygen in a reaction that releases energy for the cell to use in other activities. - The by-products of this reaction are water and carbon dioxide. The structures of the respiratory system are divided into two parts: the upper respiratory tract and the lower respiratory tract. Upper Respiratory Tract - Nose - Pharynx - Larynx Lower Respiratory Tract - Trachea - Bronchi - Lungs - Nose (rhino/o, nas/o) - The nose is the entrance to the respiratory tract. The nostrils (nares) are the external openings of the nasal cavity. - The **nasal cavity**, which is the area behind the nose, is lined by mucous membrane and cilia. This area helps filter out foreign bodies and warms and moistens the air. - The cilia, which are fine hairs found in the back of the nose, push the mucus up and out of the nose. - The smell, or olfactory, receptors connect to the first cranial nerve and are in the nasal cavity. The **paranasal sinuses** are air-filled cavities within the skill that are lined with mucous membrane. These sinuses have three functions: - Make bones lighter - Give resonance to voice - Produce mucus for lubrication in the nasal cavity The pharynx is the throat. It has three divisions: - Nasopharynx - Behind the nasal cavity - Contains the adenoids (nasopharyngeal tonsils) - Oropharynx - Behind the oral cavity - Contains the palatine tonsils - Laryngopharynx - Passageway for food and air - Divides into larynx and esophagus The **lower respiratory tract** consists of the trachea, bronchi, and lungs. **Trachea (trache/o)** The trachea, which is also called the windpipe, is held open by C-shaped rings of cartilage. **Bronchi (bronch/o)** The trachea divides into two primary bronchi, the left bronchus and the right bronchus. **Bronchioles** The bronchioles are smaller branches of the bronchial tree. The smallest are called the terminal bronchioles. **Alveoli** Alveoli are tiny air sacs at the end of the terminal bronchioles. Each is surrounded by a capillary network. The thin walls of the alveoli and capillaries allow oxygen and carbon dioxide to pass easily between the blood and the air in the lungs. **Pleura (pleur/o)** The Pleura is a doubled-folded membrane that covers the outside of each lung. - The **Parietal** pleura lines the thoracic cavity. - The **Visceral** pleura covers the surface of the lung. Pleural space is the airtight space between the pleural membranes. It contains a thin layer of pleural fluid to reduce friction and lubricate the pleura. **Lungs (pulm/o, plumon/o, pneumon/o)** Lungs are organs that contain the alveoli. They are divided into lobes. - Right lung has three lobes - Left lung has two lobes The diaphragm is a muscular wall that divides the thoracic cavity from the abdominal cavity. The diaphragm aids in the process of breathing. - It contracts and moves downward to decrease internal air pressure causing **inhalation (inspiration)**. - It also relaxes and elevates to increase internal air pressure causing **exhalation (expiration)**. The process of breathing is known as respiration. When you breathe in air through your nares. Your diaphragm aids in the breathing process. In inspiration, your lungs expand and push against the ribs. In expiration, the lungs contract and go back to their regular size. Important Definitions **Alveoli**: Air sacs of the lung **Bronchi**: Branches of the windpipe that lead into the lung **Diaphragm**: Muscle separating the chest and abdomen **Epiglottis**: The lid-like piece of cartilage that covers the voice box **Inspiration**: Breathing in air **Expiration**: Breathing out (exhalation) **Larynx**: Location of the vocal cords **Paranasal Sinuses**: Air-containing cavities in the bones around the nose **Pharynx**: Throat **Combining Form** **Meaning** ----------------------------- ----------------- Rhin/o; Nas/o Nose Pharyng/o Pharynx Or/o Mouth Laryng/o Larynx Trache/o Trachea Bronch/o Bronchus Alveol/o Alveolus Pleur/o Pleura Pariet/o Wall Viscer/o Internal organs Pulm/o; Pulmon/o; Pneumon/o Lungs Phren/o Diaphragm Spir/o To breathe Ot/o Ear **Prefix** **Meaning** Para- Near; beside Epi- Above; upon In- In; into; not Ex- Out; away from A-; an- Not; without **Suffix** **Meaning** --------------- ----------------------------- -al; -ic; -ar Pertaining to -ole Small; little -logist Specialist; one who studies -pnea Breathing -osmia Smell