Test 3 Flashcards
1
Q
Skeletal part of thorax
A
Bony enclosure formed by sternum, ribs and costal cartilages
2
Q
Thoracic cage
A
Surrounds and protects organs in the thoracic cavity, provides support for upper limbs and plays a role in breathing
3
Q
Superior thoracic aperture
A
Also known as thoracic inlet
Structures passing btwn the thoracic cavity and neck pass through it (trachea, esophagus etc.)
4
Q
Inferior thoracic aperture
A
Also known as thoracic outlet
Structures passing btwn the thoracic cavity and abdominal cavity pass through it
12th Thoracic verterba
5
Q
Bones of thoracic skeleton
A
Sternum and ribs
6
Q
Sternum major regions and major surface features
A
a. manubrium (articulates with first and second ribs to form sternoclavicular joints)
b. body
c. xiphoid process
d. sternal angle
e. suprasternal (jugular) notch
f. clavicular notches (articulate with clavicles to form sternoclavicular joints)
7
Q
True Ribs (vertebrosternal)
A
Pairs 1-7
Attach directly to sternum via costal cartilage
8
Q
False ribs
A
Pairs 8-10
Attach indirectly to the sternum
9
Q
Floating ribs
A
Pairs 11-12
Only attach posteriorly to the thoracic vertebrae, not sternum (no neck or tubercle)
10
Q
Important surface features of the typical ribs
A
- head
- neck
- tubercle: both articular and non-articular parts
- body (shaft): costal angle and costal groove
11
Q
Head of the ribs
A
Demifacets: superior and inferior
*TYPICAL RIB ONLY
12
Q
Intercostal spaces
A
Spaces btwn neighbouring ribs
13
Q
Typical ribs
A
3rd-9th
14
Q
Atypical ribs
A
1st, 2nd, 10-12th
Single/complete costal facets
Absent transverse costal facets (11th-12th)
15
Q
Function of the ribs
A
Provide attachment points to muscles of the back, thorax and proximal upper limb
Protect thoracic organs such as heart and lungs
16
Q
Costovertebral joint articular surfaces
A
Costal demifacets on vertebrae T1-T9, full costal facets on vertebrae T1, T10, T11, T12; heads of ribs 1-12
17
Q
Costotransverse joint articular surfaces
A
Tubercle and transverse costal facets on transverse processes of ribs 1-10
18
Q
Ligaments of costovertebral joint
A
Fibrous capsule
Radiate ligament of head
Intra-articular ligaments (only joints 2-9)
19
Q
Ligaments of costotransverse joint
A
Fibrous capsule
Medial costotransverse ligament
Superior costotransverse
Lateral costotransverse ligaments
20
Q
Movements of costovertebral joints
A
Internal rotation and elevation of head of rib (gliding)
21
Q
Movements of costotransverse joints 1-6
A
Internal rotation of neck of rib
22
Q
Movements of costotransverse joints 7-10
A
Posteromedial translation of neck of rib
23
Q
Neurovasculature of the thoracic cage
A
V: Intercostal veins (ant and post)
A: Intercostal arteries (ant and post)
N: Intercostal nerves
24
Q
Internal thoracic artery
A
O: subclavian artery
Branches: Musculophrenic artery, superior epigastric artery, upper 6 anterior intercostal arteries
25
Anterior intercostal arteries
Origin: Internal thoracic artery (upper 6), musculophrenic artery (lower 3)
26
Posterior intercostal arteries
Origin: Supreme intercostal artery (upper 2), thoracic aorta (lower 10)
27
Subcostal artery
Origin: Thoracic aorta
28
Anterior intercostal veins
Drain into: Internal thoracic vein (which drains into the brachiocephalic veins) via the Venae Comitantes of the internal thoracic artery
29
Posterior intercostal veins
Supreme intercostal vein drains into: Brachiocephalic vein
Right 4th-11th drain into: Azygos vein
Left 4th-11th drain into: Hemiazygos veins
30
Subcostal vein
Drains into: Azygos vein
31
Thoracic Nerves
Anterior rami of spinal nerves T1-T11: Intercostal nerves
Anterior ramus of spinal nerve T12: Subcostal nerve
32
External intercostal muscles
*most superficial; fibres course inferomedially
O: Inferior border of one rib
I: superior border of immediate rib below
A: elevate the ribs during forced inspiration
N: anterior rami of spinal nerves T1-T11, i.e., the intercostal nerves of the corresponding intercostal space.
33
Internal intercostal muscles
*middle layer; fibres course inferolaterally
O: costal groove of one rib
I: superior border of immediate rib below
A: depress ribs during forced expiration
N: same as external
34
Innermost intercostal muscles
*deepest; fibres course inferomedially
O: costal groove of one rib, posterior to origin of internal intercostals
I: superior border of immediate rib below
A: depress the ribs during forced expiration.
N: same
35
Transverse thoracic muscle
O: Inferoposterior surface of body of sternum and xiphoid process; sternal ends of costal cartilages of ribs 4-7
I: internal surface of costal cartilages of ribs 2-6
A: depressor of the ribs during forced expiration; Supports intercostal spaces and thoracic cage
36
Diaphragm origin
- Sternal part: xiphoid process
-Costal part: lower costal cartilages and ribs 7-12
-Lumbar part: Medial and lateral arcuate ligaments, bodies of vertebrae L1-L3, anterior longitudinal ligament
37
Diaphragm Insertion
Central tendon of diaphragm
38
Openings of diaphragm
- Aortic hiatus
- Esophageal hiatus
- Caval foramen
- Openings for greater & lesser splanchnic nerves, and superior epigastric vessels
39
What travels through the aortic hiatus?
Aorta, azygos vein, thoracic duct
40
What travels through the esophageal hiatus?
Esophagus, branches of the left gastric artery and vein, anterior and posterior vagal trunks
41
What travels through the caval foramen?
Inferior vena cava, branches of the right phrenic nerve
42
Recesses of diaphragm
- Costo-diaphragmatic recess (posteromedial)
- Costo-mediastinal recess (anteromedial)
43
Innervation of diaphragm
- Phrenic nerves (C3-C5)
- Sensory innervation of peripheries via 6th-11th intercostal nerves
44
Blood supply to diaphragm
- lowest 5 intercostal arteries
- Subcostal arteries
- Superior phrenic arteries
45
Function of diaphragm
- Main muscle responsible for respiration
- Increases abdominal pressure during defecation, vomiting, and voiding
- Applies pressure on the esophagus to prevent acid reflux
46
Abdominal surface of diaphragm parts
- Skeletal muscle (sternal, costal, and lumbar parts)
- Central tendon
47
Musculotendinous structures of abdominal surface of diaphragm
- Right and left crus of the diaphragm
- Median, medial and lateral arcuate ligaments
48
The heart
A hollow, cone-shaped organ that is about the size of a person’s closed fist
49
Location of the heart
- Located between the lungs in the mediastinum
- Two thirds of the heart’s mass lies to the left of the body’s midline.
50
Apex of the heart
Lower, pointed end (4th-5th intercostal space at midclavicular line)
51
Base of the heart
Broader, upper portion (2nd inercostal space and 2nd-6th costal cartilages to the right of the midline)
52
Surfaces of the heart
i. anterior surface (deep to sternum)
ii. inferior surface (resting on diaphragm)
iii. right surface (faces the right lung)
iv. left surface (faces the left lung).
53
Surface projection
outlining the dimensions of an organ on the surface of the body
54
Surface projection of the heart to the anterior surface of chest
i. superior right point
ii. superior left point
iii. inferior right point
**those are base
iv. inferior left point (apex)
55
Pericardium
Sac that surrounds and protects the heart
56
Portions of the pericardium
1. Fibrous pericardium
2. Serous pericardium
57
Fibrous pericardium
*superficial
Tough, inelastic dense irregular connective tissue prevents overstretching of the heart, provides protection, and anchors the heart in the mediastinum
58
Serous pericardium
*deep
Thin delicate mesothelial membrane
59
Layers of the serous pericardium
1. Outer parietal layer lines the inside of the fibrous pericardium
2. Inner visceral layer adheres to the heart’s surface
60
Pericardial cavity
Contains pericardial fluid, a lubricating fluid that reduces friction between the membranes as the heart moves.
61
Layers of the heart wall
a. Outer epicardium
b. Middle myocardium
c. Innermost endocardium
62
Outer epicaridum
Visceral layer of serous pericardium
63
Middle myocardium
Composed of thick cardiac muscle tissue
64
Innermost endocardium
Composed of connective tissue covered by endothelium that is continuous with the endothelium of the blood vessels
65
Upper/receiving chambers
- Right and Left atria
66
Auricle
Anterior pouch-like structure in the atria that allows them to hold a larger volume of blood; receive blood from major systemic (superior & inferior venae cavae) veins (right atrium) and pulmonary veins (left atrium).
67
Lower/pumping chambers
Right and left ventricles
Pump blood into systemic (aorta; left ventricle) and pulmonary (right ventricle) arteries
68
Pulmonary pump
Right atrium and right ventricle
Pumps deoxygenated blood towards the lungs
69
Systemic pump
Left atrium and left ventricle
Pumps oxygenated blood towards rest of the body
70
Three major sulci on surface of the heart
i. coronary sulcus (atrioventricular (AV) sulcus)
ii. anterior interventricular sulcus
iii. posterior interventricular sulcus
71
Where does the right atrium receive deoxygenated blood from?
Three veins
i. superior vena cava (SVC)
ii. inferior vena cava (IVC)
iii. coronary sinus
72
Superior vena cava
Brings blood from most parts of the body superior to the heart
73
Inferior vena cava
Brings blood from all parts of the body inferior to the diaphragm
74
Pectinate muscles (musculi pectinate)
Internal parallel ridges on anterior and lateral walls of the right atrium
75
Crista terminalis
- Smooth muscular ridge in the superior portion of the right atrium
- Divides the musculi pectinati and the right atrial appendage from the smooth surface of the right atrium
- Provides anatomical separation of the orifices of the IVC and the Coronary sinus
76
Interatrial septum
separates the atria
has an oval depression (fossa ovalis)
Part of right atrium
77
Right atrioventricular valve (tricuspid valve)
How blood flows from right atrium into right ventricle
Consists of three cusps (or leaflets)
78
Trabeculae carnae
Irregular surface of ridges on the internal surface of the right ventricle
79
Chordae tendineae and papillary muscles
Located in right ventricle
Ensure that the cusps of the tricuspid valve permit blood to flow into the right ventricle but prevent backflow of blood into the right atrium
80
Interventricular septum
Separates the two ventricles
81
Pulmonary valve
Allow the right ventricle to pump blood into pulmonary trunk which divides into the right and left pulmonary arteries which carry blood to the lungs
82
How does the left atrium receive oxygenated blood?
Four pulmonary veins; a pair of two pulmonary veins (one superior and one inferior) drain blood from each lung
83
Atrioventricular valve (bicuspid valve)
Allows blood flow from left atrium into left ventricle (2 cusps)
84
Left ventricle
Forms apex of heart
Also has trabeculae carneae, chordae tendineae and papillary muscles to ensure that the cusps of the bicuspid valve permit blood to flow into the left ventricle but prevent backflow of blood into the left atrium.
85
Aortic valve
Allows oxygenated blood flow from the left ventricle to the ascending aorta
86
Right and left coronary arteries
Arise from ascending aorta
Deliver blood to walls of heart
87
Ascending aorta
continuous with the arch of the aorta, which is followed by the descending aorta (which consists of the thoracic aorta and the abdominal aorta).
Branches of the aorta deliver blood throughout the systemic circulation
88
Ligamentum arteriosum
Fibrous remnant of the fetal ductus arteriosus vessel
Attached to the left pulmonary artery near its root and the inferior part of the aortic arch
89
Myocardial wall thickness and function
Atria: thin bc they pump low pressure blood into adjacent ventricles.
Ventricles: thick bc they pump higher pressure blood greater distances; the wall of the left ventricle is much thicker than that of the right ventricle
90
Fibrous skeleton of the heart
Consists primarily of four dense connective tissue rings that surround the four heart valves:
a. right atrioventricular fibrous ring
b. left atrioventricular fibrous ring
c. pulmonary fibrous ring
d. aortic fibrous ring
91
Function of fibrous skeleton of heart
provides a structural foundation for the heart valves, helps prevent overstretching of the valves, forms point of insertion for cardiac muscle bundles, and electrically insulates the atria and ventricles to ensure proper action potential propagation.
92
Heart valves
Open and close in response to pressure changes as the heart contracts and relaxes
93
Valves that prevent backflow of blood into the heart
Two atrioventricular valves: Right= tricuspid, Left= bicuspid
Two semilunar vales: pulmonary and aortic
94
Coronary (cardiac) circulation
Flow of blood through the blood vessels that penetrate the myocardium
95
Left coronary artery
Divides into the anterior interventricular branch (left anterior descending (LAD) artery) and circumflex branch
96
Right coronary artery
Divides into the posterior interventricular branch (posterior descending artery (PDA)) and the marginal branch
97
Coronary sinus
Where blood draining out of the myocardium travels
Empties into the right atrium
98
Principal tributaries of the coronary sinus
i. great cardiac vein (accompanies the LAD artery)
ii. middle cardiac vein (accompanies the PDA artery)
iii. small cardiac vein (runs parallel to the inferior margin of the right side of the coronary/AV sulcus)
iv. anterior cardiac veins (runs along the right inferior margin of the Rt ventricle)
99
Autorhythmic cells
Act as a natural pacemaker to set the rhythm for contraction of the entire heart
Form the cardiac conduction system to conduct action potentials throughout the myocardium, ensuring that the cardiac chambers contract in a coordination manner
100
Components of the cardiac conduction system
a. sinoatrial (SA) node which initiates each heartbeat and thus is the heart’s natural pacemaker
b. atrioventricular (AV) node
c. atrioventricular (AV) bundle or bundle of His
d. right and left bundle branches
e. Purkinje fibers
101
Nervous system and pace of contractions
NV can increase or decrease pace of contractions but not initiate contraction
102
Cardiac plexus
Sympathetic and parasympathetic nerves
Sympathetic: stimulate increased heart rate and cause dilation of coronary arteries
Parasympathetic: decreases heart rate
103
Systemic circulation
1. Left side of heart receives oxygenated blood from the lungs and pumps blood into the aorta which branches into smaller systemic arteries that can carry blood to organs
2. Arteries branch into arterioles, then into systemic capillaries where nutrients, wastes, gases, etc. are exchanged between the blood and the surrounding cells.
3. Capillaries merge to deliver deoxygenated (oxygen-poor) blood into systemic venules which merge to form systemic veins that carry this blood to the right atrium of the heart
104
Pulmonary circulation
1. Right side of the heart receives deoxygenated blood returning from the systemic circulation and pumps it into the pulmonary trunk which branches into pulmonary arteries that carry blood to the right and left lungs
2. In the lungs, the pulmonary capillaries are the site of gas exchange, and the blood becomes oxygenated
3. The oxygenated blood flows into pulmonary veins and returns to the left atrium
105
Mediastinum
Separates lungs into two distinct chambers
106
Pleural membrane and layers
Encloses and protects each lung
Two layers
1. Superficial parietal pleura: lines wall of thoracic cavity
2. Deeper visceral pleura: adheres to the lungs
107
Pleural cavity
Btwn the two pleurae
Contains a lubricating fluid secreted by the membranes
108
Lungs
Base: inferior portion
Apex: narrow superior portion
109
Surfaces of the lungs
- Costal surface
- Mediastinal (medial) surface
- Diaphragmatic
110
Costal surface of the lungs
lies against the ribs
111
Mediastinal surface of the lungs
Contains the hilum through which bronchi, pulmonary blood vessels, lymphatic vessels, and nerves enter and exit the lung
112
Cardiac notch
Found on medial surface of left lung
Heart rest against it
113
Left lung lobes
Superior (upper) lobe and Inferior (lower) lobe
Separated by oblique fissure
114
Right lung lobes
Superior and inferior lobe separated by upper part of oblique fissure
Inferior lobe and middle lobe separated by lower part of oblique fissure
Middle lobe bordered superiorly by horizontal fissure
115
Right main bronchus
Divides into the superior, middle, and inferior lobar (secondary) bronchi
Supplies lobes of right lung
116
Left main bronchus
Divides into the superior and inferior lobar (secondary) bronchi
Supply lobes of left lung
117
Lobar bronchi
Secondary bronchi
118
Conducting zone
Trachea
Main bronchi
Lobar(secondary bronchi)
Segmental (tertiary bronchi)
Bronchioles
119
Respiratory zone
Respiratory bronchioles
Alveolar ducts
Alveolar saccules
120
Segmental (tertiary) bronchi
Lobar bronchi divide into these in each lung
They supply air to the bronchopulmonary segments of each lung.
121
Lobules
lung unit distal to the respiratory bronchioles
composed of alveolar ducts, alveolar saccules and pulmonary alveoli
122
Respiratory bronchiole
divides into several alveolar ducts
123
Alveolar ducts
Each one terminates in a cluster of about 100 numerous alveolar saccule and pulmonary alveoli.
124
Alveolar saccule
terminal dilation of an alveolar duct and is composed of about 20–30 outpouchings called pulmonary alveoli.
125
Pulmonary alveolus
cup-shaped outpouching lined by simple squamous epithelium and supported by a thin elastic basement membrane
126
Bronchopulmonary segment
Compartments of each lung (usually 10)
Each one is supplied by a tertiary/segmental bronchus
127
Blood supply to the lungs
Pulmonary arteries and bronchial arteries
128
Pulmonary arteries and veins
Pulmonary trunk splits into left and right pulmonary arteries which deliver deoxygenated blood to the lungs
Oxygenated blood is returned to the heart by four pulmonary veins (right and left superior and inferior pulmonary veins) which drain into the left atrium
129
Bronchial arteries
Branch from the aorta and deliver oxygenated blood to the bronchi and bronchioles
130
Innervation of the lungs
Pulmonary plexus formed by branches of vagus nerve and sympathetic trunks
131
Inhalation
Process of moving air into lungs
Occurs when alveolar pressure is lower than atmospheric pressure
Expanding lungs increases volume and decreases pressure
132
Muscles of inhalation
1. Diaphragm (CONTRACTS DOWNWARDS)
2. External intercostal muscles
133
Exhalation
Process of moving air out of lungs
Increased alveolar pressure due to decreased volume of thoracic cavity and lungs
134
Forced expiration (labored breathing)
involves the contractions of abdominal and internal intercostals muscles.
135
Mediastinum
A compartment of the thorax located in the midline of the body, that contains most of the thoracic viscera, apart from the lungs
136
Borders of the mediastinum
Superior: Thoracic inlet
Inferior: Diaphragm
Anterior: Sternum and costal cartilages of 1st-5th ribs
Posterior: Vertebral bodies of superior thoracic vertebrae
Lateral: Parietal pleura of each lung
137
The thoracic plane (of Ludwig)
Imaginary line extending from the sternal angle, anteriorly, to the T4-T5 intervertebral space, posteriorly
Divides the mediastinum into superior and inferior mediastinal divisions
138
Inferior division of mediastinum
further subdivided into anterior, middle, and posterior compartments by the pericardial sac
139
Anterior mediastinum
Posterior to the body of the sternum and anterior to the pericardium
140
Middle mediastinum
bounded by the pericardium, which encloses the heart and origins of the great vessels
141
Posterior mediastinum
posterior to the pericardium and anterior to the vertebrae
142
Pericardial sac
Structures located anterior to the pericardial sac belong to the anterior mediastinum
Structures located posterior to pericardial sac= posterior mediastinum.
Structures located in and around the pericardial sac= middle mediastinum
143
Structures that course longitudinally through the superior and inferior mediastinum
esophagus, azygos veins and vagus and phrenic nerves
144
Esophagus
courses longitudinally throughout the mediastinum, posterior to the trachea and main bronchi and anteromedial to the azygos vein.
145
Lymphatics of mediastinum
Most of the mediastinal organs drain into the thoracic duct
EXCEPT: the right side of the thorax with the right side of the head drains into the right lymphatic trunk
146
Contents of the superior mediastinum
Thymus, trachea, superior part of superior vena cava, aortic arch and its branches (brachiocephalic trunk, left common carotid artery and left subclavian artery), esophagus, vagus and phrenic nerves.
147
Contents of the anterior mediastinum
Remnants of the thymus
148
Contents of middle mediastinum
Pericardial sac and heart
Roots of superior and inferior vena cava
Pulmonary trunk, pulmonary arteries, and pulmonary veins
Root of aorta
Main bronchi
Phrenic nerves
149
Contents of posterior mediastinum
- Descending thoracic aorta and its branches.
- Azygos veins and hemiazygos venous systems
- Esophagus and esophageal plexus
- Thoracic duct & cisterna chyli
- Vagus nerves (left & right)
- Sympathetic trunk; greater and lesser splanchnic nerves
150
Function of abdominal wall
- Protection of the internal abdominal organs
- Stabilization and rotation of the trunk
- Increase of intra-abdominal pressure (involved in coughing, defecating, vomiting)
151
Layers of the abdominal wall
From superficial to deep:
- Skin
- Superficial fascia
- Muscles
- Transversalis fascia
- Extraperitoneal fat (extraperitoneal fascia)
- Peritoneum
152
Two main sections of the abdominal wall
Anterolateral wall and posterior abdominal wall
153
Anterolateral abdominal wall main layers
Four main layers
1. Skin
2. Superficial fascia
3. Muscles and associated fascia
4. Parietal peritoneum
154
Posterior abdominal wall
Formed by the lumbar vertebrae, pelvic girdle, posterior abdominal muscles and their associated fascia
155
Muscles of the anterolateral abdominal wall
1. Lateral flat muscle group: external oblique, internal oblique and transversus abdominis
2. Anterior vertical muscles: rectus abdominus
156
Muscles of the posterior abdominal wall
Psoas major and minor muscles
Iliacus muscle
Quadratus lumborum muscle
157
External oblique
*outermost muscle; fibres run inferomedially
O: 5th-12th rib (connected w serratus ant and lats)
I: anterior layer of rectus sheath
158
Internal oblique
*beneath external oblique; fibres run superomedially
O: thoracolumbar fascia, iliac crest and iliopectineal arch
I: lower costal cartilages and linea alba
*In men, caudal fibres extend to te spematic cord and merge to form the cremaster muscle
159
Semilunar lines
Lateral margins of rectus abdominis muscle
Formed by divisions of internal oblique
Extend from the tip of the 9th costal cartilage to the pubic tubercle.
160
External oblique aponeurosis
Extends medially to the linea alba and caudally to the iliac crest and the pubic bone
Its inferior margin forms the inguinal ligament
161
Transverse abdominus
*deepest; fibres run horizontally
O: inner surface of the lower costal cartilages, thoracolumbar fascia, iliopectineal arch and iliac crest
I: Linea alba
*caudal fibers are also involved in the formation of the cremaster muscle
162
Transversalis fascia
separates the anterior abdominal wall from the extraperitoneal fat
Posteriorly it is continuous with the thoracolumbar fascia
163
Rectus sheath
Formed by the aponeurosis of the three lateral abdominal muscles
Divided into anterior and posterior layers
164
Posterior layer of rectus sheath
Superior three quarters of the sheath
Inferior limit=arcuate line
Consists of aponeuroses of the internal oblique and transversus abdominis muscles
165
Arcuate line
where the inferior epigastric artery and vein perforate the rectus abdominis
166
Anterior layer of rectus sheath
Above arcuate line
Consists of the aponeuroses of the internal and external oblique,
167
Rectus abdominus
Fibres run vertically, separated by linea alba
Consists of a string of four fleshy muscular bodies connected by three narrow bands of tendon (tendinous intersections) *six pack
O: Pubic symphysis, pubic crest
I: xiphoid process, costal cartilage of ribs 5-7
168
Arteries of the anterolateral abdominal wall
- Internal thoracic artery and its branches (musculophrenic artery, superior epigastric artery)
- 10th and 11th posterior intercostal arteries and subcostal arteries
- Inferior epigastric artery (branch of External Iliac artery)
- Deep and superficial circumflex iliac arteries
169
Arteries of the posterior abdominal wall
- Abdominal aorta and its branches: subcostal artery, inferior phrenic artery and lumbar arteries
170
Veins of the anterolateral abdominal wall
- Superior and inferior epigastric veins
- Thoracoepigastric vein
- Subcostal vein
171
Veins of the posterior abdominal wall
- Inferior vena cava and its tributaries: inferior phrenic veins, lumbar veins, and common iliac veins
172
Nerves of the anterolateral abdominal wall
Thoracoabdominal nerves
Lateral cutaneous branches of intercostal nerves 7-11, and subcostal nerves
Iliohypogastric and ilioinguinal nerve (L1)
173
Innervation of the skin and peritoneum of the anterolateral wall
T7 to L1 spinal nerves
174
Innervation of muscles of the anterior abdominal wall
Lower six thoracic nerves, the iliohypogastric nerve and the ilioinguinal nerve
175
Nerves of the posterior abdominal wall
Aortic and periarterial nervous plexuses (Autonomic nervous plexsuses)
176
What is the largest serous membrane in the body?
Peritoneum
177
Two main layers of the peritoneum
1. Parietal peritoneum: lines the wall of the abdominopelvic cavity
2. Visceral peritoneum (serosa): covers some of the abdominal organs
178
Peritoneal cavity
Located btwn the layers of the peritoneum
contains lubricating serous fluid
179
Intraperitoneal
The structures that are almost completely enveloped by visceral peritoneum and attach to the abdominal walls by a mesentery
180
Intraperitoneal structures
Liver (except at the bare area)
spleen
stomach
first part and fourth part of the duodenum
jejunum
ileum
cecum
vermiform appendix
transverse colon
sigmoid colon
181
Retroperitoneal
Structures that lie between the parietal peritoneum and posterior abdominal wall
Not supported by a mesentery
Have a layer of parietal peritoneum resting on their anterior surface
182
Retroperitoneal structures
2nd, 3rd parts of the duodenum
pancreas (except tail)
ascending colon and descending colon
suprarenal (adrenal) glands
kidneys
ureters
upper rectum
aorta and IVC
183
Major folds of the peritoneum
1. Greater omentum
2. Falciform ligament
3. Lesser omentum
4. Mesentery
5. Mesocolon
184
Function of the major folds of the peritoneum
a. bind viscera of the gastrointestinal tract to each other and to the walls of the abdominal cavity
b. contain blood vessels, lymphatic vessels, and nerves that supply the abdominal organs
185
Greater omentum
“fatty apron” in front of the abdominal viscera
extending from the greater curvature of the stomach and the duodenum downward anterior to the small intestine
186
Falciform ligament
attaches the liver to the anterior abdominal wall and diaphragm
187
Lesser omentum
Suspends the stomach and duodenum from the liver and is a pathway for blood vessels entering the liver
188
Contents of the lesser omentum
Hepatic portal vein, common hepatic artery, and the common bile duct, along with some lymph nodes
189
Mesentery
Largest peritoneal fold
Binds the jejunum and ileum of the small intestine to the posterior abdominal wall
Forms a double-layered structure at its origin
Between the two layers are blood vessels, lymphatic vessels, and lymph nodes associated with the jejunum and ileum
190
Mesocolon
Two folds
1. Binds transverse colon to the posterior abdominal wall (transverse mesocolon)
2. Binds the sigmoid colon to the posterior abdominal wall (sigmoid mesocolon)
191
Four main regions of the stomach
1. Cardia; opening of the esophagus into the stomach
2. Fundus
3. Body
4. Pyloric part
192
Three main regions of the pyloric part of the stomach
a. pyloric antrum: connects to the stomach’s body
b. pyloric canal: leads to the pylorus
c. pylorus :leads to the duodenum
193
Gastric folds (gastric rugae)
Folding of the stomach mucosa
Allow stomach to accommodate food
194
Pyloric sphincter
Controls movement of chyme from stomach to duodenum
195
Lesser curvature of the stomach
concave medial border
196
Greater curvature of the stomach
convex lateral border
197
Arterial supply of lesser curvature of stomach
Left gastric (branch of celiac)
Right gastric (branch of hepatic proper)
198
Arterial supply of greater curvature of stomach
Left and right gastro-omental arteries
Left = branch of splenic artery
Right = branch of gastroduodenal artery
199
Venous supply of stomach
All same names as arteries
Drain into hepatic portal vein
200
Arterial supply of the fundus and body of the stomach
Short gastric and posterior gastric arteries (branches of splenic)
201
Parasympathetic innervation of stomach
vagus
202
Sympathetic innervation of stomach
celiac ganglia
203
Small intestine
site of most digestion and almost all absorption of nutrients
extends from the pyloric sphincter to the large intestine.
204
Three regions of small intestine
1. Duodenum
2. Jejunum
3. Ileum
205
Duodenum
C- shape tube that starts at pyloric sphincter of stomach and merges with the jejunum
206
Parts of the duodenum
- Superior limb: connects w pylorus of stomach; intraperitoneal
- Descending limb: contains a major and minor duodenal papilla that receive the terminal ends of the main pancreatic duct and the common bile duct; retroperitoneal
- Inferior limb: retroperitoneal
- Ascending limb: empties into jejunum; retroperitoneal
207
Jejunum and ileum
Jejunum= Left upper quadrant of the abdominal cavity
Ileum= right lower quadrant
Jejunum begins at the duodenojejunal flexure and ileum ends at the ileocecal junction
*no clear demarcation separating the two
208
Arterial arcades
Anastomoses of the jejunal and ileal arteries which are branches of superior mesenteric artery.
209
Vasta recta
Straight capillaries coming off from arcades
210
Blood supply to jejunum and ileum
Superior mesenteric artery
211
Vasta recta and arterial arcades of jejunum
Long vasa recta and single raw arterial arcades in its mesentary
212
Vasta recta and arterial arcades of ileum
vasa recta that are short and arterial arcades that are numerous but very short
213
Ileal orifice
- Smooth muscle sphincter where ileum joins the large intestine
- allows chyme from the ileum to enter the cecum
214
Innervation of small intestine
Via superior mesenteric plexus
branches of the plexus contain postganglionic sympathetic fibers, preganglionic parasympathetic fibers, and sensory fibers (which are both vagal and of spinal nerves).
215
Three principle regions of the large intestine
1. Cecum
2. Colon
3. Rectum (terminates in anal canal)
216
Cecum
small blind pouch in the lower right portion of the abdominal cavity; intraperitoneal (lacks mesentery)
217
Appendix (vermiform appendix)
Attached to cecum
218
Mesoappendix
attaches the appendix to the inferior part of the mesentery of the ileum
219
Four segments of the colon
1. Ascending colon
2. Transverse colon
3. Descending colon
4. Sigmoid colon
220
Ascending colon
Ascends on the right side of the abdominal cavity to the right colic (hepatic) flexure; retroperitoneal
221
Transverse colon
Travels horizontally to the left colic (splenic) flexure; intraperitoneal
222
Descending colon
Descends on the left side of the abdominal cavity to the level of the iliac crest; retroperitoneal
223
Sigmoid colon
Travels medially from the left iliac crest to the level of the third sacral vertebra; intraperitoneal
224
Rectum
Descends anterior to the sacrum and coccyx; terminates at anal canal
225
Anus
Opening to the exterior
226
Anal sphincters
1. Internal anal sphincter: smooth muscle tissue (involuntary)
2. external anal sphincter: skeletal muscle tissue (voluntary)
227
Branches of the superior mesenteric artery
Right colic artery
Middle colic artery
Ileocolic artery
228
Branches of the inferior mesenteric artery
Left colic artery
Sigmoid arteries
Superior rectal artery
229
Blood supply to ascending colon
right colic and ileocolic arteries
230
Blood supply to the transverse colon
middle colic artery
231
Blood supply to the descending colon
the left colic artery
232
Blood supply to the sigmoid colon
Sigmoid arteries
233
Liver
Heaviest gland of the body and the largest internal organ of the body
234
Location of the liver
Located under the diaphragm in the upper right quadrant of the abdominal cavity between vertebral levels T7-L2
235
Surfaces of the liver
Diaphragmatic surface: convex
Visceral surface: flat concave
236
Visceral surface of liver
Covered with visceral peritoneum except at the porta hepatis and gallbladder fossa
237
Ligaments of the liver
Falciform ligament
Ligamentum teres
Coronary ligament
238
Porta hepatis
passage for structures to pass to and from the liver
Structures are the Portal triad: the hepatic portal vein, hepatic arteries and common bile duct
239
Gallbladder fossa
where the gallbladder rests against the liver
240
Principal lobes of the liver
Right lobe (large)
Left lobe (small)
241
Left lobe of liver
Inferior quadrate lobe
Posterior caudate lobe
242
Falciform ligament
Separates right and left lobes of the liver
243
Ligamentum teres
Free border of the falciform ligament
Extends from liver to the umbilicus (remnant of the umbilical vein)
244
Common hepatic duct
Formed by the union of the right and left hepatic ducts
Carries bile from the liver
245
Common bile duct
Formed by the merging of the common hepatic duct and the cystic duct from the gallbladder
Drains bile into the descending limb of the duodenum
246
Hepatic artery
provides oxygenated blood to the hepatic sinusoids.
247
Hepatic portal vein
delivers deoxygenated blood into the hepatic sinusoids
248
Parasympathetic innervation of liver
vagus
249
Sympathetic innervation of liver
Greater splanchnic nerves via celiac ganglia
250
Gallbladder
Pear shaped sac in a depression of the inferior surface of the right lobe of the liver
251
Parts of the gallbladder
1. fundus
2. body
3. infundibulum
4. neck
252
Blood supply of gallbladder
cystic artery (arises from the right hepatic artery)
blood drains into cystic veins
253
Innervation of gallbladder
branches from the celiac plexus and the vagus (X) nerves
254
Pancreas
Located posterior to greater curvature of the stomach; retroperitoneal
255
Four main regions of the pancreas
1. Head: contains uncinate process
2. Neck
3. Body
4. Tail
256
Ducts formed by the pancreas
1. Pancreatic duct: joins the bile duct from the liver and gallbladder to form the hepatopancreatic ampulla (ampulla of Vater)
2. Accessory duct: empties into the duodenum
257
Hepatopancreatic ampulla
Enters the duodenum at the major duodenal papilla (below the pyloric sphincter)
258
Blood supply of pancreas
Superior and inferior pancreaticoduodenal arteries, splenic and superior mesenteric arteries
Blood drains into veins of the same name and eventually into the hepatic portal vein.
259
Innervation of pancreas
Autonomic nerves from celiac and superior mesenteric plexuses; includes preganglionic vagal, postganglionic sympathetic, and sensory fibers
260
Urinary system
1. two kidneys
2. two ureters
3. One urinary bladder
4. One urethra
261
Location of the kidneys
Above the waist between the peritoneum and the posterior abdominal wall (retroperitoneal)
Btwn T12- L3, on the Left side
Btwn L1-L4 on right side (slightly lower)
262
Hilum of the kidney (renal hilum)
Ureter, blood vessels, lymphatic vessels and nerves pass through it
263
Three layers of protecting tissue around the kidney
1. Inner renal capsule: dense irregular CT; protects kidney
2. Intermediate perirenal fat capsule
3. Outer renal fascia: dense irregular CT that anchors kidney to surrounding structures and to abdominal wall
264
Two distinct regions of the kidney
1. Outer light red layer (renal cortex)
2. Inner dark red-brown region (renal medulla)
265
Renal medulla
- contains renal pyramids whose apexes are called renal papillae
266
Renal columns
portions of the renal cortex that extend btwn the renal pyramids
267
Renal lobe
portion of a kidney consisting of a renal pyramid and the renal cortex above it
268
Nephrons
Functional units of the kidney that produce urine
269
Path of filtrate
1. Produced from nephron
2. Drains into papillary ducts
3. Drains into minor calyces
4. Minor calyces merge to form major calyces
5. Major calyces deliver urine to renal pelvis
6. Urine exits kidney by flowing into a ureter
270
Renal sinus
Cavity in the kidney that accommodates the renal pelvis, renal calyces, neurovasculature and fat
271
Blood flow through kidneys
1. Right and left renal arteries
2. Right and left renal veins (each exits at the renal hilum)
272
Innervation of kidney
Celiac and aorticorenal ganglia and renal plexus of the sympathetic part of the ANS
Parasympathetics have little to no effect on the kidney.
273
Function of ureters
transport urine into the urinary bladder
274
How is transport of urine into the bladder accomplished?
i. peristaltic waves
ii. hydrostatic pressure
iii. gravity
275
How do the ureters attach to the bladder?
Enter the base of the urinary bladder medially at an oblique angle from the posterior aspect
Physiological valves prevent backflow of urine
276
Blood supply to the ureters
renal arteries, testicular or ovarian arteries, common iliac artery, and inferior vesical arteries; blood drains into the corresponding veins
277
Innervation of ureters
Renal plexus
- Sympathetic: lesser and lumbar splanchnic nerves
T10-L1
278
Urinary bladder
a hollow, distensible muscular organ (held in place by folds of the peritoneum) located in the pelvic cavity posterior to the pubic symphysis
279
Location of urinary bladder depending on gender
males: anterior to the rectum
females: anterior to the vagina and inferior to the uterus
280
Trigone
Small triangular area on floor of bladder
Two posterior corners: ureteral openings
Anterior corner: the internal urethral orifice
281
Layers of the wall of the urinary bladder
1. Inner mucosa
2. Intermediate detrusor muscle
3. Outer layer
282
Intermediate detrusor muscles of the bladder
a. inner longitudinal layer
b. middle circular layer
c. outer longitudinal layer
283
Inner mucosa of the bladder
Urothelium lying over lamina propria; allows bladder to continually inflate and deflate to accommodate varied urine volumes
284
Outer layer of bladder
Adventitia on posterior and inferior surfaces
Serosa on superior surface
285
Urethral sphincters
1. Internal urethral sphincter: opening of urethra in bladder
2. External urethral sphincter: inferior
286
Micturition (urination)
Stimulation of stretch receptors by urine initiates nerve impulses to micturition centre which in turn initiates a parasympathetic spinal micturition reflex
287
Parasympathetic spinal micturition reflex
contraction of the detrusor muscle and relaxation of the internal urethral sphincter; simultaneous somatic relaxation of the external urethral sphincter occurs
288
Blood supply of bladder
the superior, middle, and inferior vesical arteries; blood drains into the internal iliac vein.
289
Innervation of urinary bladder
hypogastric sympathetic plexus and partly from the second and third sacral nerves (pelvic parasympathetic splanchnic nerve).
290
Urethra
small tube leading from the internal urethral orifice in the floor of the urinary bladder to the exterior
291
Location of urethra in females
posterior to the pubic symphysis and embedded in the anterior wall of the vagina; leads to the external urethral orifice, which is located between the clitoris and vaginal opening
292
Layers of the wall of the female urethra
1. Deep mucosa: epithelium and lamina propria
2. Superficial muscular layer: continuous with that of the urinary bladder and consists of circularly arranged smooth muscle fibers; transports urine only
293
Regions of the male urethra
1. Prostatic urethra: passes through prostate
2. Intermediate (membranous) urethra: passes through deep perineal muscles
3. Spongy urethra: passes through penis
294
Layers of the wall of the male urethra
1. Deep mucosa: epithelium and lamina propria
2. Superficial muscular layer
295
The greater (false) pelvis
Extends from the ASIS to the pubic symphysis
Considered part of abdomen
296
The lesser (true) pelvis
Between the pelvic inlet and the pelvic outlet (a plane between inferior aspect of pubic symphysis and tip of coccyx)
Bounded by the pelvic surfaces of the hip bones, sacrum and coccyx
Contains and supports elements of the urinary, GI and reproductive systems
297
Pelvic inlet
Bounded by linea terminalis
298
Linea terminalis
Formed by:
1. Pubic symphysis
2. Pubic crest
3. Pectineal line (superior ramus of pubis)
4. Arcuate line of ilium
299
Posterior continuum of linea terminalis
Ala of the sacrum (anterior border)
Sacral promontory
300
Pelvic inclination
The angle that the plane of the pelvic inlet forms with the horizontal plane
301
Pelvic outlet
Bounded by:
- pubic symphysis (inferior margin)
- inferior rami of pubis and ischial tuberosities
- sacrotuberous ligaments
- tip of coccyx
302
Pelvic diaphragm
Consists of levator ani and coccygeus muscles
303
Levator ani muscles
O: pubic bone, the tendinous arch of the levator ani muscle, and the ischial spine
Fibres divide into:
i. The puborectalis muscle.
ii. The pubococcygeal (pubococcygeus) muscle.
iii. The iliococcygeal (iliococcygeus) muscle
304
Openings of the pelvic diaphragm
1. Urogenital hiatus: urethra and genital canal pass through
2. Rectal hiatus: rectum passes through
305
Insertion of Puborectalis
Some fibres form external anal sphincter
Some fibres form a retrorectal sling behind rectum
306
Insertion of pubococcygeal and the iliococcygeal muscles
Either on anococcygeal ligament or directly onto the coccyx
307
Coccygeus muscle
O: tendon from the ischial spine
I: Coccyx
308
Function of levator ani
Resists intra-abdominal pressure
Bears weight of pelvic contents
Closure of rectum
309
Innervation of pelvic diaphragm
The Sacral plexus (S2-S4) (via the pudendal nerve)
310
Ligaments of the pelvic wall
- sacrospinous
- sacrotuberous
311
Functions of the ligaments of the pelvic wall
they stabilize the sacrum on the pelvic bones by resisting the upward tilting of the inferior aspect of the sacrum
312
Sacrospinous ligament
Apex: attached to the ischial spine
Base: sacrum and the coccyx
313
Sacrotuberous ligament
Superficial to sacrospinous
Base: attached iliac spine, sacrum and coccyx
Apex: attached to ischial tuberosity
314
Greater sciatic foramen
superior to the sacrospinous ligament and the ischial spine
315
Lesser sciatic foramen
inferior to the ischial spine and sacrospinous ligament between the sacrospinous and sacrotuberous ligaments.
316
Obturator canal
Bordered by obturator membrane, obturator muscles, and the superior pubic ramus
The obturator nerve and vessels pass from the pelvic cavity to the thigh through this
317
Muscles of the pelvic wall
Lateral walls: Obturator internus and piriformis
318
Hip bone
1. Pubis
2. Ilium
3. Ischium
*synostose in acetabular fossa
319
Pubic bone
1. Body
2. Superior ramus
3. Inferior ramus
320
Illium
1. Body
2. Iliac wing
321
Ischium
1. Body
2. Ramus
322
Ischial spine
separates the greater sciatic notch from the lesser sciatic notch
323
Perineum
diamond-shaped area that’s divided into the urogenital triangle anteriorly and the anal triangle posteriorly
324
Urogenital triangle
Bounded posteriorly by the interischial line
325
Perineal membrane
a sheet of fibrous tissue and has thickened attachments along the borders of the urogenital triangle; also known as inferior fascia of urogenital diaphragm
326
Muscles contained within the perineal membrane
1. the Bulbospongiosus (medially)
2. the Ischiocavernosus (laterally)
3. the Transversus perineal muscles (superficial & deep) (posteriorly)
327
Innervation of the muscles within the perineal membrane
Pudendal nerves (sacral plexus)
328
Anal triangle
Borders laterally on the ischiorectal fossa.
329
Ischiorectal fossa
Located between the urogenital diaphragm and the pelvic diaphragm
Contains abdominal fat, pudendal artery, vein and nerve, and the inferior rectal nerve and artery
330
Inferior rectal nerve and artery
Supply the anal canal and external anal sphincter
331
Perineal body
Fibromuscular mass located in the middle of the interischial line, btwn the two triangles
332
Muscles attached to the perineal body
i. The external anal sphincter
ii. Bulbospongiosus
iii. The transverse perineal muscles
333
Testis
Paired, ellipsoid-shaped structure located in the scrotum for sperm production
334
Epididymis
Firm, highly coiled tube attached to the posterior surface of each testis
335
Parts of the epididymis
1. Head
2. Body
3. Tail; continuous with ductus deferens (vas deferens)
336
Function of epididymis
Facilitate the maturation of spermatozoa
337
Spermatic cord
Formed by the ductus deferens and surrounding neurovasculature
338
Ejaculatory duct
Formed by the ductus deferens and the duct of the seminal vesicles
339
Male Urethra
Expels urine and sperm
340
Three major accessory glands of the male reproductive system
1. Seminal vesicles
2. Prostate glands
3. Bulbourethral glands
341
Parts of the penis
1. Root: conatins bulb of penis and the paired crus of penis
2. Body: consists of three erectile tissues
3. Glans
342
Erectile tissues of the body of the penis
- Unpaired corpus spongiosum
- paired corpus cavernosa
343
Location of the vagina
Extends from uterus to vulva
Posterior to urinary bladder
Anterior to rectum
344
Upper end of vagina
Attached to cervix of uterus
Form a pouch (vaginal fornix)
345
Lower end of the vagina
Vaginal orfice
Opens into the vaginal vestibule
346
Blood supply of the vagina
Branches of the internal iliac artery; uterine, vaginal, and internal pudendal arteries.
347
Innervation of the vagina
Inferior hypogastric plexus (Lesser splanchnic (T12-L1) and pelvic splanchnic nerves (S2-S4))
348
Parts of the uterus
1. Body
2. Fundus
2. Cervix
349
Body of the uterus
Connected to the uterine (fallopian) tubes
Base is the fundus
Internal chamber is the uterine cavity
350
Peritoneal pouches of the female pelvis
1. Rectouterine pouch (of Douglas) ANT
2. Vesicouterine pouch (uterovesical pouch) POST
351
What covers the uterus?
Peritoneum
352
Peritoneal ligaments of the uterus
- Broad ligament (mesometrium and mesovarium)
- Round ligament
353
Blood supply of the uterus
Uterine artery which arises from the internal iliac artery
354
Normal pelvic orientation of the uterus
Anteverted anteflexed posture
355
Abnormal pelvic orientation
Retroverted retroflexed
356
Anal coloumns
Series of longitudinal ridges on the superior portion of the rectum
357
Anorectal junction
Border btwn rectum and anal canal
Formed by superior ends of anal columns
358
Anal valves
Join the inferior ends of the anal columns
359
Anal sinuses
Recesses superior to anal valves
360
The pectinate (dentate) line
Indicates the junction of the superior part and inferior part of the anal canal
361
Innervation of the internal anal sphincter
Autonomic fibres of the rectal plexus
362
Innervation of external anal sphincter
Inferior rectal nerve (branch of pudenal)
363
Blood supply of the rectum
Superior to pectinate line: superior rectal artery (branch of inferior mesenteric)
Inferior to pectinate line: inferior rectal artery
364
Middle rectal artery
Forms an anastomosis with the superior and inferior rectal arteries resulting in redundant blood supply.
365
Venous drainage origin of rectum
External rectal and internal rectal venous plexuses
366
Venous drainage of rectum
Above the pectinate line: portal system
Below the pectinate line: caval system (IVC)
367
Anal canal origin
Where the ampulla of the rectum narrows at the level of the U-shaped sling called the anorectal flexure
368
Puborectalis muscle
Maintains the anorectal flexure in resting state and via active contraction
369
Termination of anal canal
Anus
370
Where does the internal iliac artery supply?
Pelvic wall and organs, gluteal region, and medial compartment of thigh
371
Branches of the internal iliac artery
- Parietal branches: Iliolumbar, superior and inferior gluteal arteries, lateral sacral arteries, obturator, and internal pudendal artery.
- Visceral branches: superior and inferior vesical, uterine and middle rectal arteries.
372
Where does the external iliac artery supply?
Lower limb, muscles, and skin of the lower abdominal wall
373
Branches of the external iliac artery
Inferior epigastric, deep circumflex iliac arteries
374
Veins of the pelvis
Most drain to internal iliac artery then to inferior vena cava
Exceptions:
Superior anorectal vein → inferior mesenteric vein
Right/left testicular (gonadal) veins → inferior vena cava/left renal vein
375
Bronchopulmonary segment
Compartments of each lung (usually 10)
Each one is supplied by tertiary/segmental bronchi
376
Compartments of female pelvis
1. Anterior: urethra and bladder
2. Middle: uterus and vagina
3. Posterior: rectum, anal canal and anus
377
What bronchi enter the hilum?
Primary bronchi
378
Which bronchi have cartilage?
idk
379
Which surface of the lungs faces the heart?
Mediastinal surface
380
What way does the diaphragm move when contracting?
Inferiorly
381
Sternal angle
Junction of manubrium and body of sternum
382
Crista terminalis
Located in right atrium
383
Fossa ovalis
Located in right atrium
384
Where do the gonadal vessels run?
Alongside the abdominal part of ureter
385
Retroperitoneal parts of duodenum
Inferior and descending
386
Intraperitoneal parts of duodenum
Ascending and superior
387
Innervation of anus
Lumbar splanchnic
Superior hypogastric
Inferior hypogastric
