Chapter 25, 2nd half of lecture Monday 11/30

Digestive 2nd half – chapter 25
Review:
Know for practical:
Frenulum
Palates
Uvula
Arches/fauces
Tongue
Teeth/gingival

*submandibular salivary gland makes the most saliva – you want to know that
*parotid salivary gland makes amylase and is the largest – know that too
*slide #33, you want to know these slides and be able to tell the gland types, serous, mucous, mixed, etc. This will be on the practical, most likely.
*1.5 liters of saliva per day
*know sympathetic response vs parasympathetic response as far as salivation goes
*know the difference between incisors and canines, as these are things he mentioned in review as maybe being test questions – slide 39
*dental surfaces, might want to know which surface is what, see slide #40
*phases of swallowing, good to know – slide #42 – whatever the phase is is determined by where the food is.
*slide 48 – fair game for practical, know parts/regions of stomach
*remember you want to know the specific mesenteries noted in previous lecture, greater omentum, etc.
*know rugae of stomach – slide 50 – which are the striations inside stomach
*slide 53, can only be in stomach, might be on test, 3 layers of muscle
*know that mucous, pepsin, gastrin and HCL are all made in “gastric pits” by gastric glands.

NEW:
Small intestine
Finishes chemical digestion process, responsible for absorbing most nutrients
Ingested materials spend 12 hours (at least) in the small intestine
About 20 feet long. Ileum longest, jejunum, next longest, duodenum is shortest. So backwards, since DJI, they come in the opposite order.
Duodenum
**know “duodenal papilla” be able to find it on a model (medial part of duodenum) – this is where bile and pancreatic secretions enter duodenum.
this is where some accessory organs come into play – liver and gall bladder – which add bile to emulsify fats, and the pancreas adds buffers and enzymes.
Jejunum
Middle portion of small intestine
Absorption mostly starts here
7.5 feet about, ish, long
Ileum
Last segment of small intestine
10.8 feet ish in length
right lower quadrant
distal end terminates at “ileocecal valve”, a sphincter that controls the entry of materials into cecum of the large intestine

Histology: only 2 layers of muscle, see slide 68
You want to know plicae circularis or “plica”
Walls and plica are covered with villi, which increase absorption
Slide 69 would be good to know:
villi
Crypts
Goblet cells
Microvilli
Lamina propria – important layer – capillary network is here, this is where nutrients can be absorbed, also lacteals of the lymphatic system are here, which transport large fatty protein complexes that can’t enter the capillary beds. – slide 70

Difference in submucosa in DJI
D – submucosal glands
J – basic structure of plica and folds
I – peyers patches – lymphoid nodules

LARGE INTESTINE
Look for ileocecal valve, know this*
Large intestine begins at ileum and ends at anus
Almost completely frames the small intestine
About 5’ long
It would be great to know slide #73, parts of large intestine
*cancer most likely in colon below the splenic flexure, down in the descending colon, sigmoid colon and rectum
Absorbs fluids and ions, then compacts indigestible wastes– turns them into feces and stores that until defecation.

Cecum: first portion of large bowel (note the ileocecal valve** and the appendix)
Colon: this is the largest portion of the large bowel
Ascending – originates at ileocecal valve
Makes a 90 degree turn towards left at the hepatic flexure
Transverse – starts at hepatic flexure, straight across to splenic flexure (left colic flexure)
Descending - originates at left colic flexure (splenic)
On left side of abdomen
Contacts iliac fossa and terminates at sigmoid colon
Sigmoid – shaped like S sort of, and terminates at rectum. Turns inferomedially and is suspended by sigmoid mesentery.
Rectum: the final 15 centimeters of the large bowel which expands to store fecal material prior to defecation
3 thick transverse folds call rectal valves to insure fecal material is retained
terminates at anal canal
Anal canal –
terminal centimeters of large intestine
Anal columns line internal surface
Anal sinuses secrete mucin for lubrication
Internal and external anal sphincters open and close anal canal during defecation. Internal is involuntary, external is voluntary

BRBPR – hemmoroids are #1 cause of this.

Blood supplied by superior and inferior mesenteric arteries

HISTOLOGY of large intestine
Simple columnar
Thinner walls, no villi
Goblet cells make mucin, more lymphoid nodules
SLIDE 90 – one of these 3 will be on test
Longitudinal muscle layer is reduced to bands called taenie coli*
Haustrum – sacs*
Omental appendices (epiploic appendages)*

Accessory glandular organs
Liver –
upper right quadrant
Four incompletely separated lobes
Right (larger)
Left (smaller)
Caudate (inferior)
Quadrate (next to gall bladder)
Slide 94 – shows ligaments and r/l lobes
Slide 95/96 – might want to know the veins here, as this was gone over in class
*porta hepatis - where afferent artery and veins enter liver
*hepatic portal artery/vein – blood supply to liver (richer in nutrients as it’s had less filtration)
*hepatic vein – drainage of liver to inferior vena cava

LIVER HISTOLOGY:
Hepatocyte – liver cells with microvilli
Hexagonal in shape
Lobule – stacked plates, as in spokes of wheel
Filtration of HPV around the lobule into the sinusoids, which drain peripherally into a central vein
Sinusoidal capillaries – run in the spokes of the wheel, and are lined with large numbers of Kupffer cells (type of macrophage which gets rid of pathogens, damaged cells and heavy metals)
“PORTAL AREA” corners of each hexagon –
has a “triad”
*HPV branch
*hepatic artery branch
*bile duct branch
*know this as it is often on the test, what comprises a triad, etc.
Hepatocytes have bile canaliculi between each cell, which move away from central vein to bile ducts
L/R bile ducts become common bile duct
Bile secretion – know slide 101/102
Common hepatic duct leaves the liver and can move bile to either:
Common bile duct
Cystic duct
Bile emulsifies fat and can come from either gallbladder storage or directly from the liver where it is produced.

Gall Bladder
Pearshaped hollow organ which stores bile
Attached to inferior surface of liver
Concentrates and stores bile
*know cystic duct, which leads away from gall bladder, joins common hepatic duct and makes common bile duct superior to duodenum
*know fundus, body and neck of gall bladder
gallstones are “cholelisthiasis” which are hardened concentration of bile salts
*duodenal papilla, you need to know this
“Sphincter of Oddi” which controls flow from common bile duct and pancreatic ducts and limits bile flow into duodenum

Pancreas:
Exocrine functions
Pancreatic juices flow into duodenum via pancreatic duct (exocrine duct) and major duodenal papilla – pancreatic juices are made by acinar cells (enzymes and buffers)
Slide 109 histology – you might want to know the pancreatic islets.

double check online histology slides if you have time and feel like finding some:
pancreas
gall bladder
large intestine
ileum
jejunum
duodenum
stomach
esophagus
trachea
3 types of salivary gland

11/25 Wednesday lecture notes - Digestive System, Ch. 25

Simplified: Digestive system is a tube. Sure, it’s a tube that gets twisty and kinky, but mostly just a tube from mouth to anus.
Additions to the tube (associated organs): Pancreas, liver, gall bladder
Modifications to the tube: teeth, gums, salivary glands (three paired sets) give off amylase/mucin to break down carbohydrates, stuff that helps you take in food and expel waste.

Digestion
Carbs in the mouth
Protein in stomach
Fats in small intestine

Small intestine mnemonic: “Don’t Jump In”
DJI: duodenum, jejunum, ileum

In a nutshell:
Ingestion
Mechanical processing
Digestion (chemical processing)
Secretion and absorption of nutrients
Compaction and expulsion of waste

Histology of the digestive tract (slide #4 – 8)
Epithelium: (glandular) varies from simple stratified to columnar with microvilli
Mucosa: membranous layer
Submucosa: dense irregular CT, large vessels and lymph, glands to buffer PH/produce enzymes, *Meissner’s Plexus which is a network of nerve fibers in the submucosal layer
Muscularis mucosa: smooth muscle, two thin layers of smooth muscle ( one is circular and one is longitudinal – for peristalsis), some elastic fibers, and helps shape the lumen
Muscularis externa: two thick layers of smooth muscle – for peristalsis, also both circular and longitudinal, includes sphincters, and movements are coordinated by
*Aurerbach’s myenteric plexus
Serosa: serous membrane, outermost layer visceral peritoneum. Is present in all areas for attachment EXCEPT in: oral cavity, pharynx, esophagus, rectum

Layers of the Ileum – slide 10, be able to label and know
Plica with folds and microvilli (mucosal fold)
Mucosa – goblet cells
Muscularis mucosa
Submucosa – remember NAV
Muscularis externa
Serosa

Peristalsis and Segmentation
How a bolus of food moves down the tube, in short.
Peristalsis is how the longitudinal AND circular muscles move it down the tube
Segmentation is breaking up the bolus into smaller bits, mixing and churning, and that’s what the circular muscles do.

**The smooth muscle of the GI tract go through spontaneous depolarization, somewhat like the heart – triggered by chemicals, hormones and physical stimulation

Peritoneum – see slide #13
Lining of the cavity in abdomen
Two continuous layers – all one sheet both visceral and parietal layers
7 liters of peritoneal fluid made per day to lube up the gutty bits
Organs are all either “intra” or “retro” that is to say in or behind the peritoneum.

Mesenteries (not in our text, see slides 14 – 17) know starred
Fused double sheets of the serous membrane which stabilize positions of attached organs, and prevent tangling during peristalsis. Keeps them from twisting or torquing.
Each mesentery has a different name, should know them off this slide
Omentum
lesser omentum
between stomach and liver
*Mesocolon
Large intestine, transverse and sigmoid colon
*Greater omentum
(this is where the beer belly comes from!)
hangs from the stomach
Parietal peritoneum
*Mesentery proper
Holds the small intestine in place
Visceral peritoneum

Blood supply:
Abdominal GI tract supplied by 3 unpaired arteries
Celiac trunk
Superior mesenteric
Inferior mesenteric

Innervation
Autonomic and sensory
Three autonomic plexuses
Celiac plexus
Superior mesenteric plexus
Inferior mesenteric plexus

**Should know the path food takes from mouth to anus
Should know slide #21 – organs, be able to identify, spend some time on this

Oral cavity
Slide #23, fair game for exam would be stuff like tonsils, salivary glands, uvula, landmarks in general
*labial frenulum
*uvula
*maybe arches or falces

Fauces are opening from oral cavity to oralpharynx
Laterally paired muscular folds are:
Glossopalatine arch
Pharyngopalatine arch
Palatine tonsils are between these two arches

Salivary glands
Parotid – largest of the thre paired glands and secrete 25-30% of saliva
Submandibular (don’t worry about knowing all the ducts, just know the glands) – produce about 70% of saliva
Sublingual

Two types of secretory cells which secrete a combination of mucous and serous material
Know slide #33, might be either on written or practical
Produce about 1 – 1.5 liters of saliva per day
Parasympathetics increase saliva production
Sympathetics decrease production (dry mouth, fight or flight)
Regulated by CN’s VII, IX, X (taste buds) and CN IV (object in mouth)

Teeth, slide 35 and 36
Enamel
Dentine
Crown
Neck
Roots which fit into the alveoli of the maxilla or mandible
Cementum covers the roots
Know the root canal
Periodontal ligaments
Pulp
6-30 months – 20 milk teeth, or deciduous teeth
adult teeth or permanent teeth are 32
incisors – 2 pairs
canines – 1 pair
bicuspids – 2 pairs
molars – 3 pairs
eight pairs up and eight pairs down, 32 teeth!
Might review dental surfaces but he didn’t spend much time on them in lecture

Pharynx
Shared by the respiratory and digestive systems
Muscles include pharyngeal constrictors
Elevators
movers of the soft palate
swallowing – movement of food bolus from oral cavity to esophagus
3 phases of swallowing
buccal
pharyngeal
esophageal
*first peristalsis movement takes place in esophagus

Esophagus (present in both thoracic and abdominal cavities, mostly in thoracic)
In upper right quadrant
In thorax (mediastinum)
10 inches long, enterior to vertebral bodies
**esophageal hiatus or “inferior esophageal sphincter – where it connects to stomach (about 1.5 cm in to the abdominal cavity), prevents reflux
It is quite possible to get a hiatal hernia, unfun
**Superior esphegeal sphincter, at unction of pharynx and esophagus

Stomach
Upper left quadrant
Mechanical and chemical digestion of food bolus, which is processed into “chyme”
3 layers of muscle aid in mechanical processing
longitudinal layer (outer)
circular layer (middle)
oblique layer (inner)
**TEST QUESTION**
REGIONS OF THE STOMACH
fundus – upper dome
cardia – adjacent to esophagus
body – largest region
pylorus – final funnel where chyme empties to duodenum

**SLIDE 52, what are folds? Answer “RUGAE”
Stomach wall:
Lined by simple columnar epithelium
Indented by numerous depressions called “gastric pits”

Slide #54, know the layers
Histology: along and at base of gastric pits slide 56
Cells:
Surface mucous cells
Mucous neck cells
*Parietal cells – HCL
*Chief cells – Pepsin
*Enteroendocrine cells - Gastrin

We made it to about slide #45 and will complete the lecture on Monday, 11/30

Ch 22 Vessels and Circulation

When studying: arteries, by convention, are red. Veins will be shown in blue.

Three classes of blood vessels
Arteries – carry blood away from the heart, become progressively smaller, branch and become capillaries
Veins – return blood to the heart and become progressively larger.

Artery and vein walls have “tunics” – 3 of them
1. Tunica adventitia – connective tissue that anchors the vessel to the organ
Contains blood supply of their own **vasa vasorum – supplies the larger blood vessels themselves.
2. Tunic media – circularly arranged smooth muscle and elastic fibers
Sympathetic – vasoconstriction
Parasympathetic – vasodilation
3. Tunica intima – endothelial cells, simple squamous, lining artery and veins, plus some elastic tissue. (cracks and fissures in this layer gives cholesterol a place to cling to, so causes some problems later in life, given age and diet)
SEE SLIDE #5
Know types.
ARTERIES and VEINS
Larve Veins and Elastic Arteries – the largest vessels
Medium vein and Muscular artery – next size down
Venule (no muscle layer) and Arteriole (smooth muscle around them)
Fenestrated Capillary (vein) and Continuous capillary (artery)**
**Oxygenation only happens in capillary beds, not anywhere else. VERY important.
Slide #8, idealized slide, you want to know this and what to look for in Wednesday’s lab. *note, nerves, arteries and veins often run together – think NAV

Arteries vs.veins
More adventitia media – thicker walls,
Veins are thinner, more collapsible. “Collapsability” is a term associated with veins

Arteries – large to small
1. Elastic
Largest are approx 1”. Ex: aorta, pulmonary, brachiocephalic, common carotids and subclavians. Most of these are near the heart – they have to be elastic so that they can handle the pressure of flow, stretch under increased pressure. Elastic arteries then branch into the next size down, which is muscular. Elastic is present in all 3 tunics of these vessels.
2. Muscular
Medium diameter, elastic fibers are only in 2 of the tunics.
Internal elastic lamina – between intima and media
External elastic lamina – between media and extrema

3. Arterioles – 30 micrometers
Six cell layers of smooth muscle in media, control flow of blood between capillaries and venules, sympathetic innervation – vasoconstriction (increased blood pressure) and parasympathetic innervation – vasodilation (decreased pressure.)

Capillaries – smallest and most delicate of vessels
Diameter is only slightly larger than an erythrocyte
Walls are solely comprised of tunica intima
**only vessel where metabolic exchange can occur between blood and cells outside of the bloodstream.

Types of capillaries **KNOW slides 17 - 19
typical capillaries consist of an endothelial tube and a basal lamina
in the fenestrated capillary there are pores and tiny openings.
1. Continuous **
a. Tight junctions, complete endothelium, most areas of the body
2. Fenestrated **
a. Pores, no junctions, incomplete endothelium
3. Sinusoidal
a. In the liver, larger pores

Capillary BEDS
**You want to know slide #20, it will be on the test.
Know the flow, and be able to identify structures.
Basically, arterial flow (oxygenated blood) comes in, venous flow (deoxygenated blood) goes out, carrying Co2 back to lungs.
In some cases, arteries can send blood directly to the vein, bypassing capillary bed. “arteriovenous anastomosis”
Know:
arteriole
metarteriole
Precapillary spincters
True capillaries
Thoroughfare channel
Postcapillary venule

Anastamosis – direct connection between vessles
Guarantee reliable blood supply to match need of tissue
Smooth muscle directs flow

VEINS:
Veins collect blood from all tissues and organs and return it to the heart.
Walls are thinner and less elastic – there’s no pressure so they don’t need to be, pressure in veins is lower but diameter is larger than corresponding artery
At rest, veins hold about 60% of the body’s blood. Veins function as blood reservoirs.
Venules:
• Smallest veins which collect blood from capillaries
• Go with arterioles in the hierarchy
• Smallest ones are postcapillary venules, at distal end of capillary bed
• Smaller and medium sized veins travel with muscular arteries
• Blood pressure is too low to overcome gravitational pull, so skeletal muscles help pump blood towards the heart as they contract. This process is the skeletal muscle pump.

Large veins
Include great veins
Superior and inferior vena cava
Med large veins have thicker adventita
Outer layers are elastic/connective tissue

Valves in veins – slide 28
Valves oppose the force of gravity, to prevent backflow

**There’s a great set of flow charts on page 584, 592, 593 of the text, with the branchings and different arteries and veins in the upper and lower extremities.
Arterial flow – out of and away from the heart - THORAX
Oxygenated blood pumps out of left ventricle into ascending aorta which gives off into two branches. Right and Left coronary arteries. These supply the heart itself.
The aortic arch gives off three branches
a. braciocephalic trunk
first one off the arch, and “bifurcates” into right common carotid and right subclavian
b. left common carotid
not totally symmetrical, this is the branch in the middle of the arch
c. left subclavian
this is the last branch off the aortic arch
Descending Aorta – follows aortic arch and branches to the thoracic wall – renamed the descending abdominal aorta when it passes inferior and posterior to the diaphragm
At L4 – descending abdominal aorta bifurcates –first branch point
Left common iliac artery
Right common iliac artery
Then almost immediately again divides into
Internal iliac artery
External iliac artery

Arterial Flow through HEAD AND NECK –
brachiocephalic trunk – slide #34**
bifurcates into subclavian and right common carotid
At the superior border of the thyroid cartilage, the right common carotid bifurcates into internal and external carotid arteries. (see slide 36)
External carotid gives rise to arteries on the face, outside of cranium.
Internal carotid – supplies blood to the base of the brain.

At first rib, braciosephalic branches into Subclavian artery branches DOWN into
Inernal thoracic artery
And UP into
Vertebral artery – through transverse foramen of cervical vertebra

Venous blood return from cranium – HEAD AND NECK
From internal and external jugular veins (flipflopped)
Drain into subclavian vein
Becomes brachiocephalic vein
Becomes superior vena cava

Internal Carotid – supply to brain:
Enter cranium through carotid canal
Divide into anterior and middle cerebral arteries
*circle of WILLIS – gets blood supply from both carotid arteries (internal) and vertebral arteries **THIS WILL BE ON THE TEST** “cerebroarterial circle”

Vertebral arteries enter cranium through foramen magnum and merge to form the basilar artery which goes up to make the back side of the circle of willis with the carotids forming the anterior portion.

Venous drainage of cranium – most venous blood drains through dural venous sinuses
Superior sagittal sinus
Inferior sagittal sinus
Straight
Left and right transverse sinus
Sigmoid sinus

Internal Thoracic Artery
Arises from subclavian artery, then flow downward
Give rise to anterior intercostals
Then superior epigastrics

SLIDE #44 – try to be able to label this for exam, you should be good to go
Try to find landmarks for branchings if you can, this might help.

Venous return from thorax
All venous drainage from the thorax drain on the (left side) hamiazygos and (right side) accessory hemiazygos which drain into superior vena cava.

Blood flow to support lung tissue:
Bronchial arteries – paired arteries that branch off the descending thoracic aorta.
High, towards lungs
Esopheogeal arteries are also paired and in thorax, lower, down near stomach

Diaphragm is supplied from 3 sources
Superior phrenic arteries
Inferior phrenic
Musculophrenic

At the diaphragm and down:
3 unpaired arteries emerge from anterior wall of descending abdominal aorta
Celiac trunk
Superior mesenteric artery
Inferior mesenteric artery

The celiac trunk will give off 3 branches. Know them. *slide 52, 53
Left gastric artery – supplies lesser curvature of stomach and lower esophagus
Splenic artery – supplies spleen and part of the stomach
Common hepatic artery – liver, gall bladder and a portion of the stomach

Just inferior to celiac trunk
Inferior pancreaticoduodenal
Intestinal arteries
Jejunum and ileum
Ileocolic
Ileum, cecum and appy
Right colic
Middle colic

**Just above bifurcation of descending abd aorta, inferior mesenteric **know
Left colic
Distal transverse colon/proximal descending colon
Sigmoid
Distal descending colon/sigmoid colon
Superior rectal artery
Rectum and upper half of anal canal

Slide 58 is good for frame of reference organs/arteries

Friday lecture 11/13 end of CH 21 the heart

Test has been moved up to the Monday before Thanksgiving.
Practical will no longer be a ‘moving around’ thing, but rather, we’ll have it entirely on slides on the power point, so make sure you know those.

KNOW:
4 chambers of the heart
directionality of flow (top to bottom up, top to bottom out)
Coronary sinus
Superior vena cava
Inferior vena cava
Widowmaker (coronary artery)
* left marginal branch of LCA – know this from multiple angles/images
Aorta
Ascending arch
Arch of aorta
Descending aorta
Pulmonary veins
Interventricular sulcus
Coronary sulcus
Orient and identify posterior and anterior heart
Chordae tendinae
Papillary muscles

NEW:
Conus arteriosus – high smooth area at the top of the R ventricle just before the pulmonary semilunar valve
*coronary arteries are the first to get oxygenated blood from the heart. These are what need to be bypassed whent hey get clogged.
L ventricle
Thicker
Extra thickness to force blood around systemic circuit
Know trabeculae carnae
Papillary muscles
Chordae tendinae
Ventricles/differences
R:
thinner
AV valve has three cusps
L:
thicker
AV valve has two cusps

Coronary arteries, slide 45
Circulation to the muscle of the heart (myocardium)
2 branches off the ascending aorta
KNOW
L coronary and R coronary artieries
Circumflex artery
Anterior interventricular artery
Right coronary artery

Slides 48-50
Left coronary artery
KNOW: Two main branches
Anterior interventricular
Circumflex artery

Right coronary artery
KNOW: two main branches
Posterior interventricular artery
Right marginal

Venous drainage of myocardium
Slide 52
Great cardiac
Middle cardiac
Small cardiac

Valve cycles know slide 53 for practical
(What is contracting?)
know “systole”
atria are contracting on this slide
semilunar valves are shut while AV are open

Know slide 54
Difference between ventricular and atrial systole
V systole/A systole

http://www.youtube.com/watch?v=D3ZDJgFDdk0

Autorhythmic
Cardiac muscles are conncted by gap junctions known as intercalated discs - contract as single unit
KNOW the cycle of conduction – slide 60 and 61
SA Node
down to
AV node
Know bundle branches and Purkinje fibers

P wave – when SA node goes off, before it hits the AV node
QRS complex – depolarization – ventricular – after AV node goes off
T wave is when the whole heart repolarizes

Slide 64 – purkinje fibers
Also “bundle of his”

Slide 67 and 68 – know coordinated sequence of heart chamber contractions/cardiac cycle
SA generates an impulse
Atria contract (systole) while Ventricles relax (diastole)
Impulse to AV node then to ventricles
Ventricles contract (systole) while atria relax (diastole)

Normal rhythm vs too fast or slow
Too fast = tachycardia
Too slow = brachycardia

Additional innervation to the heart outside of autorhythmic cells
Also innervated by divisions of the ANS – sympathetic ( makes it contract more quickly, fight or flight, etc, starts with neurons in T1-T5) and parasympathetic (make it contract slower, less forcefully - off medulla oblongata via left and right vagus nerves)

Anatomical components of both divisions make up the coronary plexus

**Sympathetics increase rate and force of contractions
**Parasympathetics, decreases rate but has no effect on contractions

Aging:
Nothing gets better – some issues and what is affected
Murmurs, sounds caused by changes in valves - VALVES
Hypertrophy, enlargement of the heart - MYOCARDIUM
Decreased conduction/electrical abnormalities – NERVES
Lifestyle caused issues, diet/exercises - VESSELS

the heart, slides 1-40, ch 21, Monday 11/9 lecture

Test review – 5 extra points given to everyone, questions 10, 38 44, 57, and 62 were thrown out due to general confusion about them.

CH 21 notes – the heart
“The fastest way to a man’s heart is through the ribs. Though it’s a little bit easier if you go under and then up.”

Size of a fist
100,000 beats per day
small organ made of muscle, and circulates blood on demand
1.5mil gallons of blood per year

Four chambers and four valves – remember “four by four”
*just an overview, more detail further down
Atria (2) UP
Ventricles (2) DOWN
A over V
Four valves, unidirectional flow
R – blue (pulmonic)
L – red (systemic)

Circuits
Pulmonary – to and from lungs/gas exchange
Systemic 02 to tissues/CO2 to lungs
Oxygenated blood is red
Deoxygenated blood is blue (exception is the lungs)

Heartbeat
blood pressure, which indicates how effectively the heart is pumping blood, how hard it has to work to get the blood through the body, what you are measuring is the force of the blood pushing against inside walls of blood vessels
Atria beat first followed by ventricles
Minimum pressure is necessary for circulation

Arteries – transport away
Veins – transport towards
Capillaries – small thinwalled vessels, interconnect with smallest veins and arteries

Through the heart – slide #7, know
Blood FROM body (deoxygenated), TO the right side of the heart
IN to the R atria from superior and inferior vena cava
TO the R ventricle below, pumps OUT
TO the lungs (R and L both sides equally via the pulmonary arteries)
BACK TO the lungs via the pulmonic veins, now oxygenated
TO L atrium, then
TO L ventricle, then out of the heart via the aorta to the systemic arteries
**you want to know the order of this pathway by Friday
also know the various valves, and where they are**

Geographic location and position of the heart (slide 9/10)
a. Runs from ribs 3-5
b. It is DEEP to the sternum, slightly LEFT of midline in the mediastinum (compartment of the thorax)
c. RIGHT border of the heart rests on the diaphragm, inside its happy little pericardial cavity **KNOW this border, you don’t need to know the others so much**
d. heart is rotated a little bit anteriorally and to the right, so that the left side of the heart ends up sitting a little bit posterior

TERMS – regarding positioning
Posterosuperior surface
Superior border
Apex
Inferior border

Pericardium
Fibrous sac that holds the heart in place, also lines the pericardial cavity
Lined by serous membranes
*pericarditis would be an inflammation of the heart, kind of painful
OUTER – fibrous
INNER – serous membrane
Parietal layer – lines the inner surface of the fibrous layer
Visceral layer – covers outer surface of the heart
*see slide 16
ORDER: superficial to deep
Fibrous pericardium
Parietal pericardium
Pericardial cavity (full of fluid, allows heart to float freely)
the following make up the wall of the heart
Visceral serous pericardium (epicardium)
Myocardium – muscle of the heart
Endocardium – lines the atria and ventricles

Heart wall: **slide 18, you want to know this slide
Epicardium
Myocardium
Endocardium
*know intercalated discs
*know that the heart is “autorhythmic”, the cells of the heart beat on their own

EXTERNAL heart anatomy – slide #19
**be able to identify the difference between anterior structures and posterior**
Anterior
a. auricle (be able to find it on the right side at least, smaller on the left)
b. Coronary sulcus – fatty valley between atrium and ventricle
c. Anterior Intraventricular sulcus – fatty valley between ventricles
*(know the difference between these two)
Posterior
a. Superior vena cava
b. Coronary sulcus
c. Coronary sinus – *refers to a special vessel feeding the heart’s own blood supply not a cavity as we are used to thinking of the term ‘sinus’
d. posterior interventricular sulcus
e. atria and ventricles
*the heart has its own circulation

4x4 – four chambers and four valves
Chambers:
Atria (2)
Ventricles(2)
Valves
“AV valves” (valves between atria and ventricles)
(2) atrioventricular valves
R is tricuspid, Left is mitral aka bicuspid
(2) Semilunar valves (pulmonary and aortic)

How blood moves around the heart:
Right atrium – deoxygenated venous blood flows IN to the R atrium>> via 3 veins
a. coronary sinus (blood from heart muscle itself)
b. superior vena cava (blood from head and neck)
c. inferior vena cava (blood from the lower body)
THROUGH:
Tricuspid valve – blood rushes through the right AV valve (tricuspid). Contraction of the right AV valve snaps the valve shut, preventing backflow.
*know chordae tendinae,
know what leaflets of the valve are
know location of tricuspid valve*
TO:
Right Ventricle –
*know Papillary muscles
know cusps
conus arteriosus*
THROUGH:
Pulmonary semilunar valve (which is also tricuspid)

Blood is oxygenated in lungs, then THROUGH
L atrium via pulmonary veins
This atrium has a smaller auricle
(left AV bicuspid valve) and into L ventricle
thicker wall, larger ventricle
then THROUGH
aortic semilunar valve
and into aorta
and then to system. This is where the blood is also fed to coronary arteries.

Wed 11/4 lecture - Cardiovascular

*noted during lecture, study pictures in chapter as this material might be pictorial in nature for the practical. Familiarize yourself with most of the diagrams*

Blood - function
1. transport of oxygen, nutrients, chemicals and waste gasses
a. 02 - lungs to body cells
b. C02 - body cells to lungs, exchange for oxygen, C02 exhaled
c. Nutrients - GI tract to body tissues
d. Hormones - endocrine glands to body cells and tissues
e. waste products (non gas) - via plasma to kidneys, excreted in urine
2. regulation of body temperature, ph balance, fluid volume
a. normal fluid level is "normovolemic"
b. dehydrated/low fluid level is "hypovolemic"
3. protection

Blood characteristics
1 degree warmer than the body
alkaline pH (7.35 to 7.45)

Immune response
monitors pathogens
immobilizes using antibodies
destroys pathogens using white cells

Whole blood
made up of plasma and formed elements
the male body has approximately 5-6 liters of blood
the female body has approximately 4-5 liters of blood
blood is slightly viscous and kind of sticky
If you look at a vial of blood that has been centrifuged, a typical sample, it will look stratified. The layers are comprised as follows:
50-55% plasma
44% erythrocites
<1% "Buffy Coat" - leukocytes and platelets

Plasma components
1. 92% water
2. 7% proteins
a. Albumins (smallest, approx 60%, most abundant) - think transport protein and delivery system (ions, lipids, hormones) - CARRY
b. globulins (35%, alpha/beta), antibodies - FIGHT
c. fibrogen - (4%, plasma protein) healing and clotting - CLOT
<1% regulatory proteins
3. 1% other solutes

Alpha and Gamma Globulins - Transport proteins
synthesized in liver
attach to lipids and carry things all over the body

Gas exchange
Plasma and interstitial fluid are basically the same thing, but the percentage of dissolved gasses and protein is higher in plasma than in extracellular fluids, that's how they travel around the body.

Formed elements
red and white cells and platelets
hematocrit - % of volume of formed elements in whole blood
varies along gender lines
M - 40-50%
F - 47-57%
99.9% of formed elements are red blood cells
.1% are platelets and white blood cells

*lecture note, you will want to be able to identify elements on a blood smear slide*

Erythrocytes (red blood cells)
biconcave
no nuclei or organelles
only job is to carry oxygen around
line up in a "rouleau" formation, a tidy straight line, to get through small places.
short life span, 3-4 months, 1% of your total erythrocytes are renewed daily
can't synthesize their own repair materials
old RBCs are removed via the liver and the spleen
PACKED CELL VOLUME = the percent of RBC in a sample
there are about 280 hemoglobin molecules per erythrocyte
2 alpha, 2 beta - make chains, 4 heme molecules - see page 536
Every 4 hemoglobin molecules contain FE2+ (iron)
and each hemoglobin molecule can bine 4 O2 or 4 CO2 molecules

Blood type
surface antigens - markers on surface of erythrocytes create blood "types", which are assigned into ABO groups.
Rhesus factor - another surface antigen, further typifies ABO blood types into "positive" or "negative", but has been designated as surface antigen "D" for some reason.

O- is the universal donor. Very popular at blood bank holiday parties.
AB+ is the universal recipient. Very lucky when in trauma centers. For some degree of luck and it could be argued that the bad luck of being in the trauma center at all trumps blood type, but you get my point.

**lecture note - you will want to know what agglutination is, why it happens and how. Basically? wrong blood type or RH factor, you get clumping, the cells can hemolyze and DEATH occurs, so you wind up dead like a big dead thing. Very bad. Do not recommend it. Read labels carefully and double check all bag labels against charted blood type that the hospital blood bank sends up, if you are going into the nursing field.**

WHITE BLOOD CELLS
leukocytes
nucleus and organelles are present
respond to pathogens and initiate immune response
some WBC can leave blood vessels (diapedesis) and go to peripheral tissues during immune response
"chemotaxis" - the attraction of WBC to site of injury
not enough WBC - leukopenia
too many - leukocytosis

Types:
Granulocytes - end in "phil", make up about 60-70% of WBC
neutrophil, eosinophil, basophil - cannot leave vessels
Agranulocytes - end in "cyte"
monocytes and lymphocytes - totally can leave vessels and go walkabout
Lymphocytes - 3 types:
T cells
B cells
Natural Killer cells

Platelets
made by megakaryocytes
continuously produced in red marrow
1/4 the size of RBC
work to make clots and patch damaged vessels until they heal, with actin and myosin fibers.