Basic & gross structures of the Respiratory system

Question 1

Thorax

Answer 1

An osseo-cartilaginous framework (12 thoracic vertebrae, sternum and the 12 ribs) to form the convex shape of the thoracic cage. Protects the main components of the respiratory and circulatory system. The ribs all have a ROM, allowing the thoracic cage to expand, allowing the lungs to inflate.

Question 2

Alveolus (Alveoli)

Answer 2

The air sacs found at the end of the respiratory tract in the respiratory zone of the lung (where diffusion takes place between the air and the pulmonary capillaries). Walls = 1 cell thick (simple) and the cells are flat (squamous). This allows diffusion of CO2 & O2. There is over 300 mil. alveoli in the lungs arranged for the largest SA:V.

Question 3

Respiratory zone of lung

Answer 3

The areas of the lungs where O2 and CO2 diffuse via the simple squamous epithelium of the alveoli either from the air spaces in the alveoli to the haemoglobin in the blood of the capillaries (O2) or vice versa (CO2).

Question 4

Lobes of lungs

Answer 4

The lungs are made up of 3 lobes (R) or 2 lobes (L). These subdivisions (2x superior, 2x Inferior and 1xmiddle) are due to the trachea splitting into that many bronchi, making it possible for lobes to be removed surgically

Question 5

Segments of Lungs

Answer 5

The largest functional divisions of the anatomical lobes; each receiving their own air and blood supply.

Question 6

Pulmonary Capillaries

Answer 6

The junction points between the pulmonary arteries and the pulmonary veins. They surround the alveoli and are the blood vessels are were CO2 and O2 are exchanged. They are only 1 cell thick to allow for quick passive diffusion and contain haemoglobin for the O2 to bind to.

Question 7

Mediastinum

Answer 7

The mediastinum is a division of the thoracic cavity; it contains the heart, thymus gland, portions of the Oesophagus and trachea, and other structures. It forms a complete septum across the chest and divides superiorly & inferiorly. If deflected in a certain direction this may indicate to a pressure variation between the pleural cavities.

Question 8

Hilar Shadows

Answer 8

A composite radiographic shadow of the lymph nodes, central pulmonary arteries and veins. Infection caused by fungal, atypical mycobacteria, viral, tularemia, and anthrax may cause unilateral hilar enlargement.

Question 9

Costophrenic angle

Answer 9

The angle made from the diaphragm and the ribs meet (located at the most inferior lateral points of the Thorax). The angle tends be be sharp and acute, if blunted this is usually considered to represent pleural disease such as small pleural effusion or mild pleural thickening.

Question 10

Anatomical dead space (respiratory system)

Answer 10

The total volume of the conducting airways from the nose or mouth down to the level of the terminal bronchioles, and is about 150 ml on the average in humans. The anatomic dead space fills with inspired air at the end of each inspiration, but this air is exhaled unchanged.