A & P Chapter 2: Respiration

Respiration

- The exchange of gas between and organism and its environment.

Inspiration

- Bringing oxygen to the body cells by breathing in.

Expiration

- Eliminating carbon dioxide by breathing out.

Quiet Expiration

- Passive, quick, and no real muscle involved in it.
- Mix of gravity and de-torquing.
- Mostly involves diaphragm relaxing and lungs decreasing size and increasing pressure.

Forced Expiration

- Other muscles contribute in expiration.
- Requires us to contract our abdominal muscles.
o Contract and compress viscera.
- All muscles of expiration make the thoracic cavity smaller

Air Pressure

- The force exerted on the walls of a chamber by molecules of air.

Pressure Equation

- Pressure is a force exerted on an area.
o P=F/A
You can decrease pressure by adding area

Boyles Law

- As the volume of a container increases, air pressure decreases.
- As the volume of a container decreases, air pressure increases.

Boyle's Law and Respiration

- As the volume of the lungs increases, air pressure decreases.
o Forcing air into the lungs (inspiration).
- As the volume of the lungs decrease, air pressure increases.
o Forcing air out of the lungs (expiration).

Positive Pressure

- Molecules are close together and pressure has increased.

Negative Pressure

- Molecules are father apart and pressure has decreased.

Air Pressure Needs to Equal:

- The inside and the outside of the lungs.

Bony Thorax

- Comprised of the ribcage, sternum, & clavicle.
- Suspended from the vertebral column.

Aspects of the Bony Thorax

- Superior Aspect = 1st rib and clavicle.
- Inferior Aspect = 12th rib.
- Lateral Aspect = ribs.

Visceral Thorax

- Respiratory passageway (trachea, bronchi).
- Lungs
- Heart

Vertebral Column

- Part of the bony thorax.
- Composed of 33 segments of bone.
o Vertebra

How Many of Each Vertebrae?

- Cervical = 7
- Thoracic = 12
- Lumbar = 5
- Sacral = 5
- Coccygeal = 1

Cervical Vertebrae

- Vertebrae in the neck.
- Top 7
- 8 Nerves

Thoracic Vertebrae

- Vertebrae from the shoulder down the bottom of the ribcage.
- The basis for respiratory framework.
- 12 thoracic.

Lumbar Vertebrae

- Vertebrae in the back.
o Attachment for back and abdominal muscles.
- 5 lumbar.

Sacral Vertebrae

- 5 sacral.
o Fused together to form the sacrum.

Coccygeal Vertebrae

- Form the tail bone (coccyx).
- 1 coccygeal (3 fused together).

Interior Vertebral Disks

- Separate the vertebrae.
- Protect the spinal column.
- Allow the vertebrae to move.

Cervical Vertebrae - Landmarks

- Spinous Process
- Transverse Process
- Vertebral Foramen
- Superior and inferior articular facets

Spinous Process

- Bumps along the spine.
- Posterior most processes of the vertebra.

Transverse Process

- Lateral processes of the vertebra
- Goes sideways.

Vertebral Foramen

- Hole in the vertebrae that the spinal cord goes through.

Superior and Inferior Articular Facet

- The surfaces where two adjacent vertebrae meet.

Atlas - C1

- Cervical Vertebrae 1
- Skull sits on it.
- Supports skull rotation.

Axis - C2

- Cervical Vertebrae 2
- Supports skull pivot.

Pelvic Girdle

- Ilium, sacrum, pubic bone, ischium
- Strong support structure for attaching to the legs.

Pectoral Girdle

- Scapula and Clavicle bones.
- Supports the upper extremities.
- Provides A-frame to support the thoracic and back muscles.

Rib Cage

- Part of the bony thorax.
- Composed of 12 rib pairs.
- Curved barrel shape.
- Sternum serves as focal point.

Ribs

- Attach to the vertebral column.
- Slope downward during rest.
- Elevate during inspiration.

Rib Components

1. Head
2. Neck
3. Shaft
4. Angle

Rib Types

- True Ribs
- False Ribs
- Floating Ribs

True Ribs

- 7 pairs
- Ribs that connect directly to cartilage.

False Ribs

- 3 pairs
- Only one connection to one costal cartilage for all 3 ribs.

Floating Ribs

- 2 pairs
- Don't connect to the costal cartilage.

Sternum

- Cartilaginous chondral.
- Directly below the jugular notch.
- Point of attachment for the ribs.

Sternum Components

- Manubrium Sterni
- Corpus Sterni (body)
- Xiphoid Process (Ensiform Process)

Manubrium Sterni

- Top portion of the sternum.

Corpus Sterni

- Main section of the sternum.
- Body

Xiphoid Process

- Pointy part at the bottom of the sternum.
- Also called ensiform process

Respiratory Passageway

- Connects the lungs to the outside.

Respiratory Passage Protection

- Safeguards lungs against pollutants.
- Warms and humidifies air as it enters the lungs.
o The nasal passages warm and humidify air better and are better at filtering air than the oral passage.

Bronchial Tree

- The branching of large tubes into smaller tubes
- Trachea -> Bronchial Tubes -> Bronchioles -> Alveoli

Trachea

- Bifurcates into the bronchial tubes.

Bronchial Tubes

- One goes left and one goes right.
- Connects the trachea to the lungs.
- Divides into bronchioles.

Bronchioles

- Smallest branches.
- End in alveoli.

Alveoli

- Grape-like structures.
- Where oxygen goes for gas exchange.
- Each alveoli have capillaries that cover them and provide blood supply.

Alveoli Capillaries

- Alveoli are covered in capillaries that provide them with blood supply.
- This is where the exchange of oxygen to the blood and carbon dioxide from the blood occurs.

Location of the Lungs

- Located in the visceral thorax.
o In the rib cage.

The Lungs are Made of:

- Vascular, elastic tissue.
- They are not a muscle.

Pleural Linings

- The lungs contain pleural linings.
- They allow the lungs to expand.

Lobes of the Lungs

- The right lung contains 3 lobes.
- The left lung contains 2 lobes.

Lung Components:

- Blood
- Arterial & venous networks
- Connective tissue
- The respiratory pathway
- Alveoli
- Pleural Linings

Alveoli in the Lungs: #

- The lungs contain over 300 million alveoli.
o 6 billion capillaries surround the alveoli.