Anatomy Exam One; Thorax

thoracic cavity

coelomic cavity; body cavity filled/lined with a serous membrane/serosa—membrane that lines a cavity that does not open to external environment

mediastinum

esophagus, trachea, great vessels, vagus nerve, and phrenic nerve

pericardial cavity

coelomic cavity containing the heart

pleural cavity

coelomic cavity containing the lungs

diaphragm

hypaxial muscle; defines inferior boundary of thoracic cavity

true ribs #

1-7, costal cartilages attach to sternum

false ribs #

8-10, costal cartilages attach to cartilage of rib #7

floating ribs #

11-12 do not attach to sternum

the internal muscles are innervated by the ______ nerves which are ____ of the thoracic and spinal cord

intercostal, ventral rami. lie between internal and innermost

external intercostals fiber orientation

oriented anteriorly, and inferiorly in the direction of sternum, hands in pockets, start at vertebral body and end at the start of costal cartilage

internal and innermost intercostals orientation

fibers oriented anteriorly and superiorly, hands in prayer, extend from sternum to costal angle

intercostals all have ____ origins and ____ insertions

superior,inferiror

external intercostals do what

expand and elevate the ribcage outward to increase the size of thoracic cavity

internal and innermost intercostals what do they do

depress and compress ribcage to decrease size of thoracic cavity.

left lung is smaller than the right because

the heart is angled inside leaving only two lobes and an oblique fissue

cardiac impression

depress in medial side of left lung where heart sits

cardiac notch

anterior margin of the cardiac impression

parietal pleura

serous membrane lining the thoracic cavity

visceral pleura

serous membrane attached to the surface of the lung

pleural cavity

thin fluid filled space between the pleurae

pleural sac

two layered bag holding the lungs includes the parietal and visceral pleurae

transverse thoracis origin insertion

inferior origin on sternum, superior insertion on inner surface of ribs

transverse thoracis action and innervation

a, depress ribs and compress ribcage, i, intercostal nerve

ventilation

mechanical intake and expulsion of air from lungs

changing lung volume: external intercostals

can increase size of the thoracic cavity to increase lung volume

changing lung volume: internal,innermost,transverse

can decrease size of thoracic cavity to decrease lung volume

diaphragm contraction

diaphragm flattens, increasing thoracic cavity and lung volume

diaphragm relaxation

diaphragm decreases thoracic cavity and lung volume by rebounding upwards

inspiration

external intercostals contract, diaphragm contracts, vol inc psi dec

expiration

other rib muscles contract, diaphragm relaxes, vol dec, psi inc

serous fluid allows for

lubrication, and adhesion through water molecules

which touches the heart or lung, visceral or parietal

visceral

the heart lies in the ______ and like the lungs is encases in a ____

pericardial cavity, double layer serous membrane sac

the fibrous pericardium lies over the

epicardium, including visceral and parietal layers

myocardium

middle, muscular portion

endocardium

inner heart

what is the purpose of the heart valves and interaction between chordae tendineae and papillary muscles

prevents backflow of blood in the heart

atrial contraction

ventricle fills with blood

ventricular contraction

valves close under reverse pressure

palpillary muscles relaxed allows for

bicuspid/tricuspid valves to open

papillary muscles contract with ventricles and

tension on chordae tendineae holds valves closed

coronary circulation

blood flow to and from the tissues of the heart itself

interventricular sulcus

groove on surface of the heart between ventricles

coronary artery and sinus run

along the right and left of the atrioventricular sulcus

describe blood flow from coronary artery to right atrium

blood flows from aorta into the coronary artery, flows into smaller coronary artery that enter the heart wall and into capillaries for gas exchange, flows into coronary sinus and into the right atrium

mediastinum

the superior central compartment of the thoracic cavity containing the heart, esophagus, trachea, great vessels, vagus and phrenic nerves

great vessels

major blood vessels that enter and exit the heart

left common carotid artery

supplies left side of head and neck

right common carotid artery

supplies right side of head and neck

left subclavian artery

supplies left upper limb

right subclavian artery

supplies right side of head and neck

right internal jugular vein

drains the right side of the head and neck

left internal jugular vein

drains the left side of the head and neck

left subclavian vein

drains left upper limb

right subclavian vein

drains the right upper limb

veins are symmetrical or asymmetrical

symmetrical

arteries are symmetrical or asymmetrical

asymmetrical

trachea

windpipe, rigid tube connecting the larynx to the bronchi

why is the trachea rigid

cartilage rings in the tracheal wall and bronchi prevent airway collapse

esophagus

muscular tube that moves food from pharynx to stomach.

what makes trachea and esophagus different in structure

esophagus collapses unless moving food

vagus nerve location

emerges between common carotid and internal jugular

the vagus nerves contain ___ % of the _____ neurons of the ANS

75, preganglionic parasympathetic motor

vagus nerve innervation

descends through the thoracic cavity and innervates the heart, trachea, bronchi, and esophagus

Phrenic Nerve location

forms from branches of ventral rami of C3-C5

what kind of neurons are the phrenic nerves

somatomotor

phrenic nerve innervation

the diaphragm, hypaxial, c345 stay alive

main structural difference of the phrenic nerve compared to vagus nerve

thinner, more lateral than the vagus nerve

thoracic organs receive _____ innervation from the ____

sympathetic innervation, spinal cord

preganglionic neurons emerge from the ____ horn from ____ and synapse with ______ neurons in the _____

lateral, T1-T5, post ganglionic neurons, sympathetic ganglia

bulk flow lymph

movement of water and dissolved solutes into and out of capillaries 85% of fluid is returned to capillaries

lymph

excess extracellular fluid once it has entered a lymphatic capillary

right lymphatic duct extracellular fluid

drains right upper limb, right half of thorax, neck and head into right subclavian vein

thoracic duct extracellular fluid

drains everything else into left subclavian vein