Respiratory Anatomy Flashcards
what is the thoracic inlet bound by
The first thoracic vertebra (T1) posteriorly
The first pair of ribs laterally.
The costal cartilage of the first rib and the superior border of the manubrium anteriorly
what is the thoracic outlet bound by
12th thoracic vertebra posteriorly.
11th and 12th pairs of ribs laterally.
Costal cartilages of ribs 7 through 10 and xiphisternal joint anteriorly.
what is the sternal angle and where
between manubrium and body of sternum
T4/5 vertebrae
4th intervertebral disc
what is in between ribs
intercostal muscles
what parts are in the sternum
manubrium - jugular notch
- body
- xiphoid, T10 vertebrae, rib 7
at what vertebral level is the xiphoid
T10 vertebrae, rib 7
what joint is between the clavicle and clavicle notch on sternum
saddle joint
what ribs are true ribs
1-7 rib - true ribs, connected to sternum
what type of ribs are ribs 8-10
false ribs, indirectly connected
what type of ribs are ribs 11 and 12
floating ribs, not connected to sternum
what joint is between the costal cartilage of ribs and sternum
synovial joint
what joint is between the ribs and vertebrae
plain synovial joint
describe the 1st rib and how many facets does it have
broad and flat
has 1 articular facet to attach w vertebral bodies
grooves for subclavian artery and vein
what does the head of the rib bind to
Head binds to body of vertebrae - synovial plane joint
what does the tubercle of the rib bind to
Tubercle binds w transverse process of vertebrae
how many articular facets do the ribs have (apart from 1st)
2 articular facets
what happens to the thoracic cavity on inspiration
transverse diameter increases ‘pump handle’ ‘bucket handle’ upwards and outwards
- diaphragm contracts + inc size of lung
- on forceful - need external intercostals and accessory muscles
what muscles are used on forceful expiration
internal intercostal muscles + abdominal muscles used
what are the intercostal muscles innervated by
innervated by ventral rami of thoracic spinal nerve
what are the layers of intercostal muscle and their orientation
1) superficial layer, external intercostal muscle. Inferior anterior
2) internal intercostal - inferior posterior orientated
3) innermost intercostal, orientated ^^
whats in the costal groove
neuromuscular bundles, intercostal vein + artery + nerve (VAN) between internal and innermost muscles
collateral branches
where is costal groove
between internal and innermost intercostal muscles
what is the intercostal muscles drained by
Drained by azygous vein into SVC
what supplies the thoracic wall
posterior and anterior intercostal arteries (branch from internal thoracic artery - subclavian artery) and branches from axillary arteries
what drains the thoracic wall
azygous vein
hemiazygous accessory
internal thoracic veins
what is the lymphatic drainage of the right side of the thoracic wall
Right lymphatic duct -> internal jugular vein and right subclavian vein
what is the lymphatic drainage of the left side of the thoracic wall
thoracic duct -> internal jugular vein and left subclavian vein
what is the lymphatic drainage of the left side of the breast
Breast -> axillary lymph node -> parasternal LN -> abdominal LN
how is the mediastinum divided
superior
inferior: anterior, middle, posterior
divides at sternal angle
what are the peripheral attachments of the diaphragm
to lumber vertebrae
Costal cartilage on ribs 7-12
xiphoid process of sternum
what is the central attachment of the diaphragm
to central tendon
what innervates the diaphragm
Phrenic nerve supply C3-5,
motor (from inferior surface)
sensory (supplies central part
peripheral part of diaphragm innervated by sensory fibres of intercostal nerves, T7-T12
what are crus and where does right crus come from
tendons at bottom of diaphragm
right L1-3
where does left crus come from
L1-2 + intervertebral discs
where are the diaphragm hiatuses (openings)
T8 - caval, vena cava through central tendon, phrenic nerve
T10 - oesophageal hiatus in muscle, vagus nerve
T12 - aortic hiatus, btwn right and left crust
where does the trachea bifurcate
at sternal angle level
2 primary bronchi at T4/5
what borders does the lung have
anterior, posterior, inferior
what surfaces does the lung have
costal, mediastinal, diaphragmatic
what is the peripheral part of the diaphragm innervated by
by sensory fibres of intercostal nerves, T7-T12).
where does the conducting zone and respiratory zone start
end - terminal bronchioles
start - respiratory bronchioles
where is the cardiac notch
cardiac notch at rib 4-6, lingula
what is the hilum
on mediastinal surface of lung
what is the root of the lung
group of structures that enter/leave lung through hilum - bronchus, artery, vein, lymph
what impressions are on the left lung
Aortic arch and heart + oesophagus impression on left lung
descending aorta
what impressions are on the right lung
Heart impression
inferior and superior vena cava
how many bronchopulmonary segments are there
10
what is the parasympathetic innervation of the lungs, pulmoary plexus
Parasympathetic - vagus nerve
what is the sympathetic innervation of the lungs
T2-5, bronchodilator
what arteries supply lung
2 thoracic aorta on left
1 posterior intercostal artery on right
what veins drain the lungs
azygous + accessory hemiazygous
what is the lymphatic drainage of the lungs
superficial and deep LNs - bronchomediastinal lymph trunk
what is the pleura what are the components
Outer lungs and internal thorax covered
Visceral and parietal pleura
what is in the pleural cavity, whats its purpose
Cavity filled w intrapleural fluid allows movement of lung and sticks them together
what innervates visceral pleura
autonomic NS
what innervates parietal pleura
somatic neurones, pain sensitive
Intercostal nerves, phrenic nerves
what is a recess
increased space between layers of pleura at reflection
what is reflection
where parietal pleura becomes visceral
what are some reflections in the lung
Costodiaphragmatic reflection + recess on bottom
Costomediastinal
what are the margins of the lungs
mid clavicular rib 6
mid axillary line rib 8
paravertebral line 10
what are the margins of the parietal pleura
mid clavicular rib 8
mid axillary line rib 10
paravertebral line 12
what rib does the horizontal fissure follow (right lung)
4th rib
what rib does the oblique fissure follow
begins at spine T2/3, follows 6th rib
what are the layers in the histology of the respiratory systen
mucosa (epithelium and lamina propia)
Submucosa
Cartilage
Adventitia
what are the histological features of the trachea
20 C shaped hyaline cartilage, gaps filled by trachealis muscle and fibroelastic tissue
what is the purpose of the mucosa and submucosa
warm + moisten air, trap foreign particles in mucous
describe the tracheas epithelium
pseudostratified ciliated columnar epithelium w goblet cells
Basement membrane in between
Lamina propia - contains elastin n bv
describe the sub mucosa
Mixed sero-mucous glands
where is the perichondrium
between submucosa and cartilage
what is the adventitia
connects n supports trachea to surrounding tissue
what is the extra pulmonary bronchi and its histology
2 primary bronchi
same as trachea
what is the histology of intra pulmonary bronchi
less cartilage, does not completely encircle the lumen.
layers of smooth muscle between the mucosa and submucosa
what is the diameter of bronchioles
<1mm
what is the histology of bronchioles
Ciliated columnar epithelium (non-ciliated in smaller bronchioles - terminal)
Smooth muscles inc
Clara cells - secrete surfactant
No goblet cells, no cartilage, no submucosal glands
what is the histology of respiratory bronchioles
ciliated cuboidal epithelium
what are alveolar ducts surrounded by
surrounded by smooth muscle, elastin and collagen
what are type 1 pneumocytes
alveoli cells
large flattened, v thin, diffusion take place
what are type 2 pneumocytes
secrete surfactant, decrease surface tension and stop alveoli collapsing
what cells are there in alveoli
type 1 pneumocytes, type 2 and macrophages (dust cells) - brownish
what do goblet cells do
secrete mucous
spermatogenesis
oogenesis
ff
what cell is formed when the nucelus of sperm fuses nucleus of ovum
diploid cell called the ZYGOTE
what is formed after the zygote divides a couple times
Morula
solid ball of cells
are the children affected if the mother has a mitochondrial disease
yes, all affected
what does the morula divide into and why
blastocyst
getting nutrition to central core becomes difficult
describe blastocyst
has blastocystic cavity
Cells accumulate at one end to form an inner cell mass.
outer lining of cells is trophoblast.
where does fertilisation happen
in fallopian tube
zygote to blastocyst
happens while moving from fallopian tube to uterus
ff
where does implantation occur
in the uterine endometrial layer and placenta begins to develop
how is chorion formed
cells that are outer mass of blastocyst - trophoblast
divide to form 2 layers
develop finger like processes (chorionic villi)
what does chorion do
Implantation process (chorionic villi) Forms part of the placenta in due course Secretes human Chorionic gonadotropin (HCG) (used to detect pregnancy)
at what day does implantation occur
day 7
what are fimbrae
are next to ovary
capture ovum then release into tube
what is the Decidua basalis
part of the endometrium deep to the implanted conceptus.
what does HCG do
secreted by the chorion is going to help maintain the decidua (endometrium)
what happens to the inner cell mass of the blastocyst
cells of the inner cell mass form a 2–layered flat disc called the BILAMINAR DISC
epiblast
hypoblast
2 cavities - amniotic and yolk sac
what are the 2 layers of the bilaminar disc
epiblast
hypoblast
what 2 cavities are formed with the bilaminar disc
Amniotic cavity (A) Yolk sac (Y)
when is placenta formed and matured
after 12 weeks
matured 18-20weeks
what is the function of the placenta
Foetal nutrition
Transport of waste and gases
Immune etc
describe placenta
Foetal part and surface: smooth with foetal blood vessels and end of umbilical cord
Maternal part: Decidua basalis of endometrium
Rough and has maternal blood vessels
what cavities are there in the embryo at week 2
Amniotic cavity
Chorionic cavity
Allantoic cavity
Yolk sac
what is the midline of the embryo
top of amniotic cavity
what is the Primitive streak
formed in the midline of the epiblast by the dipping in of cells (invagination)
forms axis for embryo
what is gastrulation, describe the process
Epiblast cells migrate to lie inbetween epiblast and hypoblast layers
form 3 germ layers
ectoderm
mesoderm
endoderm - trilaminar disc
cells are now specialised
what are the specialities of each layer in trilaminar disc
ectoderm - skin, NS
mesoderm - muscle, reproductive
endoderm - gut tube, resp tube
how is the notochord formed and what does it do
primitive streak keeps dividing
form cluster of cells in mesoderm, disconnect
secretes protein to induce neural tube
how is neural tube formed whats this process called
ectoderm thickens, makes crest until comes together and makes tube
neuralation
what induces the mesoderm to thicken
neural tube
what does the mesoderm seperate into
3 parts
paraxial
intermediate plate
lateral plate mesoderm
what happens to the lateral plate mesoderm, what are the sections called
it splits
somatic and splanchnic mesoderm
what does the paraxial mesoderm divide into
into 3
- dermatome
- myotome
- sclerotome (bones)
what does intermediate plate mesoderm become
urogenital system (kidneys + repro)
what does lateral plate mesoderm become
body cavity and coverings
what is teratology
congenital abnormalities and abnormal formations.
whats and (R) enantiomer
isomer
effective drug for morning sickness, positive
whats and (S) enantiomer
can cause birth defects
what are teratogens
environmental factors that cause abnormal development.
what are causes of abnormal foetus development
environmental
genetic
multifactorial
unknown
what is the risk of teratogenesis in weeks 1-2
High risk of death, low risk from teratogens
what is the risk of teratogenesis in weeks 3-8
Period of greatest sensitivity to teratogens
what is the risk of teratogenesis in weeks 9-38
Decreasing sensitivity to teratogens
what does the risk posed by teratogens depend on
Exposure during critical periods of development
Dosage of drug
Genetic constitution of embryo ie some more susceptible than others at equivalent doses etc
how can you diagnose malformations prenatally
Blood - AFP
Ultrasound scan – 12 week anomaly scan
Invasive tests: chorionic villus sampling and amniocentesis
how can you diagnose malformations postnatally
Hip stability
Testes (descent)
Fingers and toes
Hearing
what 4 structures are developed in the respiratory system
trachea
lungs
pleura
diaphragm
where does the repsiratory system develop from
foregut part of primitive gut tube
what is the gut tube formed from
endoderm
where do the trachea and lung buds bud out from and when
out from the ventral wall of the foregut
at week 4
what is the position of the trachea to the oesophagus
trachea anterior to
oesophagus
what seperates the trachea and lung buds from oesophagus
oesophagotracheal septum
what happens if the trachea and oesophagus don’t separate
Tracheoesophageal fistula (abnormal passage) Oesophageal Atresia (passage is closed/absent)
what does the splanchnic layer form
forms visceral pleura
what does the somatic layer form
forms parietal pleura
what is the pericardioperitoneal canal
space between these two layers of mesoderm around the lungs is continuous with the heart in front and the peritoneal cavity below
pleura still open to heart and abdomen
what is it called once the pericardioperitoneal canal is closed off
pleural cavity
How do the pleural cavities get closed off from the heart
fold of lateral plate somatic mesoderm will grow in from the periphery and close off pleural cavity
pleuropericardial fold
what does the pleuropericardial fold become
become the pericardium of the heart
what seperates the pleural cavity from peritoneal cavity
diaphragm
what are the stages of lung development
embryonic pseudoglandular canalicular saccular alveolar (post natal after 40weeks)
what happens in the canalicular stage
alveolar ducts form
Type 1 and 2 pneumocytes
when can gas exchange take place in the lung development stages
saccular stage
alveoli develop, surfactant
what happens in pseudoglandular stage
). Development of all lung structures except respiratory part (no gas exchange)
what structures form the diaphragm
Septum transversum
Pleuroperitoneal folds
Skeletal muscle ingrowth from the peripheral body wall (muscular part of diaphragm)
dorsal mesentery of the oesophagus
look at diagram
what is a major defect of the diaphragm
Failure of the diaphragm to completely close during development -> hernias
hernia - protrusion of an organ through the structure or muscle that usually contains it
Pulmonary hypoplasia
what does the septum transversum become
forms the central tendon of the diaphragm
what forms the diaphragmatic crura
Skeletal muscle from the periphery covers the dorsal mesentery to form the diaphragmatic crura.
