L05: Thoracic Cavity and Lungs

which cavities contain the CNS and meninges

cranial and vertebral

which body cavity contains the pleura and pericardium

thoracic

which body cavity contains the peritoneum

abdominal

what is located in the middle mediastinum

pericardium/heart

superior mediastinum boundaries

superior thoracic aperture to sternal angle, T4-T5 junction

inferior mediastinum boundaries

sternal angle, T4-T5 junction to respiratory diaphragm

which structure in the thorax lines body cavities and coats organs as they develop and expand into the cavity but does not open to the outside

serous membrane

seruous membrane that is coating an organ is called

visceral pleura

serous membrane that is coating the body wall is called

parietal pleura

function of serous membrane

lubricate and reduce friction as organs move/expand/contract against each other or the body wall

give three examples of serous membranes in the body

pleura, pericardium, peritoneum

serous membrane of middle mediastinum

pericardium

serous membrane of abdominal cavity

peritoneum

which two main structures come off of the brachiocephalic trunk

right common carotid and right subclavian arteries

what three main branches off of the aorta

brachiocephalic trunk, left common carotid artery, left subclavian artery

the descending/thoracic aorta gives rise to

posterior intercostal arteries

where do the anterior intercostal arteries originate from

internal thoracic arteries

where do the internal thoracic arteries originate from

subclavian arteries

where do the pericardiacophrenic arteries originate from

internal thoracic arteries

where do the brachiocephalic veins feed into

superior vena cava

where do the posterior intercostal veins feed into

azygous system

what are the three functions of the lymphatic system

collects ECF, solutes, and proteins and returns them to bloodstream, absorbs fat from the small intestine, and detects pathogens and activates immune response

what are the five components of the lymphatic system

lymph, lymphocytes, system of lymph vessels for transport, lymph nodes, lymphoid tissue

plasma-like watery fluid

lymph

T cells, B cells, and NK cells are all

lymphocytes

lymph node function

filter lymph

where is lymphoid tissue located

respiratory tract, GI tract, tonsils, thymus, spleen, and bone marrow

lymph from the left half and lower right half of the body drain into where

thoracic duct

where does the thoracic duct begin and then empty into bloodstream

cisterna chyli to junction of left subclavian and internal jugular veins

lymph from the upper right half of the body drain into where

right lymphatic duct

where does the right lymphatic duct empty into the bloodstream

junction of right subclavian and internal jugular veins

which nerve innervates the diaphragm and what spinal cord levels does it originate from

phrenic, C3-5

true/false: the phrenic nerve passes in behind the hilum of the lung

false (in front with pericardiacophrenic arteries/veins)

where does the recurrent laryngeal nerve originate from?

vagus nerve

true/false: the vagus nerve passes behind the hilum

true

which cranial nerve is responsible for the parasympathetic innervation for most post-cranial viscera

vagus (CN X)

which cranial nerve contributes to the cardiopulmonary plexuses, innervates the heart and lungs, and branches into the esophageal plexus

vagus (CNX)

which structure of the nervous system carries sympathetic signal up and down the body and contributes to the cardiopulmonary plexues

sympathetic trunk/chain

where is the sympathetic trunk/chain located

lateral to the vertebral column

where does the splanchnic nerve originate from

sympathetic trunk

what is the muscular tube lined with mucosa that is posterior to the trachea and heart but anterior to the vertebral bodies and carries ingested items from the throat to the stomach

esophagus

which organ is the primary site of T-cell generation and maturation

thymus

True/false: the thymus slowy degenerates beginning in adolescence and is replaced by fat

true

where is the thymus located

anterior to great vessels in superior mediastinum

which nerves are located in the parietal pleura and carry information back to the CNS

intercostal and phrenic nerves

true/false: the parietal pleura is primarily somatically innnervated

true

within pleural sac/between layers of pleura, filled with serous fluid to increase surface tension between thoracic cage and lungs, “potential space”

pleural cavity

what happens during a pneumothorax

air is introduced into the pleural cavity, tension is dispersed and the lungs can no longer expand

what is the cartilage in the trachea called

cricoid cartilage

the last cartilage ring in the trachea before the split into primary bronchi is

carina

what smooth muscle closes off the cricoid cartilage rings posteriorly in the trachae

trachealis

trachealis muscle function

changes the diameter of the trachea to accomodate swallowing and increase the force of exhalation for coughing/sneezing

what type of tissue lines the trachea

pseudostratified epithelium

what cells in the trachea help sweep dust and mucus out of the trachea

cilliated tall/columnar cells

what cells secrete muscus in the trachea

goblet cells

which cells in the trachea metabolize xenobiotics and

can replenish lining by differentiating and

dividing, secrete important proteins

clara cells

which primary bronchi tends to have more aspirated objects and why

right because it is shorter, wider, and more vertical

list the divisions of the bronchi starting with primary bronchii and ending with alveoli

primary, secondary, and tertiary bronchi, broncioles, alveoli

how many lobes does the right lung have

3

how many lobes does the left lung have

2

how many fissures does the right lung have

2

how many fissures does the left lung have

1

what are unique structures of the left lung

lingula and cardiac notch

what are the four components of each hilum

main bronchus, pulmonary artery, pulmonary veins, and hilar lymph nodes

how many segments does each lung have (regularly and clinically)

10 regular, 8 clinical

where vessels come in and out of the lung is called

hilum

true/false: each segment of the lung is encased in visceral pleura making them independent, resectable respiratory units

true

which ribs does the diaphragm span from

6-10

which structure separates thorax and abdomen, transmits structures

between spaces, and controls what comes in and out of the thorax and abdomen

respiratory diaphragm

where and how is the respiratory diaphragm anchored

surfaces of L1-L3 vertebral bodies via the right and left crus

where does the heart and pericardium attatch to the respiratory diaphragm

central tendon

what percent of relaxed breathing is the respiratory diaphragm responsible for?

60

where does the inferior vena cava and branches of the right phrenic nerve enter the diaphragm

caval hiatus

where does the esophagus and vagal trunks enter the diaphragm

esophageal hiatus

where does the aorta, thoracic duct, azygous vein and splanchnic nerve enter the diaphragm

aortic hiatus

what structures pass through the aortic hiatus

aorta, thoracic duct, azygous vein and splanchnic nerve

what structures are found in the posterior arcuate gaps of the respiratory diaphragm

origins of psoas and quadratus lumborum, sympathetic trunk, subcostal VAN

boyle’s law

pressure and volume have an inverse relationship for gasses

how does inhalation work?

the thoracic cage expands and creates a vacuum (negative pressure) to force air into lungs which are connected via the surface tension between the pleura

how does exhalation work?

thoracic cage contracts creating positive pressure that forces air out of lungs

which muscles are responsible for rib elevation

intercostal muscles, scalenes, sternocleidomastoid, serratus, pectoralis minor

what happens when the diaphragm contracts

it flattens