Anatomy Flashcards
How thick are capillaries
1 cell thick!
Just big enough for 1 red blood cell
2 types circulation
Systemic - entire body
Pulmonary - lungs
How does the body even out the pressure from the pump (heart)
Aorta expands then contracts
Evens out blood pressure
What acts as a huge pump to help return blood to heart
Known as
Gastrocnemius
Venal return
Which blood vessels transport oxygenated blood and are depicted in red
Arteries & arterioles
Which blood vessels are blue and transport deoxygenated blood
Veins & venues
Function of arteries/arterioles
Oxygenated blood AWAY from heart to body
Exception - pulmonary & umbilical arteries
Blood under high pressure
Function of veins & venues
Transport deoxygenated blood back TO heart
Exception - pulmonary & umbilical veins oxygen rich
Blood under low pressure
Why do old people have swollen ankles
No pumps in feet, venal return not good as usually inactive & dehydrated. Valves in veins fail, blood stagnates, doesn’t flow back…..
Role of capillaries
Small vessels connecting arterioles & venules
Where substances are exchanged between blood cells & tissues
Most tissues have more than 1 —- supply
Blood
Where blood vessels merge is called a
Anastomosis
What can continue to provide blood supply of circulation to tissue ceases?
Collateral circulation
What happens if an artery or vein is cut
Artery spurts - high pressure
Vein collapses - low pressure
Veins more fragile
What are 3 layers of veins/arteries called
Tunica externa (outer) Tunica media (middle( Tunica interna
Do all veins contain valves
No some
Esp those in limbs
Composition of tunica externa, media & interna in both veins & arteries
Externa - fibrous tissue, elastic & collagen fibres
Media - smooth muscle controls BV diameter by vasoconstriction/dilation
Elastic fibres allow recoil
Interna - basement membrane & endothelium in contact with blood
Structural difference between vein & artery
Arteries thicker than veins, particularly middle layer of smooth muscle/elastic tissue
Thickest layer of vein is externa, but still all thinner than artery
Describe recoil of artery facilitated by smooth muscle & elastic fibres in tunica media
Expands & snaps back
Pushes blood forward
Which vitamin is v important for collagen
C
What is a lumen
The ‘hole’ in the middle of a vein/ artery
Difference between lumen of vein/artery
Larger in vein
What happens if artery constricted
Blood pressure goes up
What causes vascular dementia
Furring of carotid artery
Lack of blood/O2 to brain
2 types veins
Deep
Superficial
What is the only layer of capillaries
Endothelial
What does the unique 1 layered structure of capillaries allow
Partly permeable
Transport of gases across blood/cells etc
Which blood vessel transports blood to brain
L & R carotid arteries
Which blood vessel feeds the arm
Subclavian artery
Which is main BV into leg
Femoral artery
Which are main veins of neck
Internal/external jugular veins
Which is body’s main artery
Aorta
Which are main veins going in/out of heart
Superior/inferior vena cava
Which BVs take deoxygenated blood to lungs
Pulmonary arteries
2 main branches of sorts
Arch of and descending
Main vein from leg
Femoral vein
Body’s main vein - 2 parts
Inferior/superior vena cava
Main BV to arm
Bronchial arteries
Body’s primary detoxification organ
Liver
Ex fat soluble vitamins
A
E
D
Ex water soluble vitamins
B
C
(Pee out)
What is big vein in liver
Portal vein
Which organs empty directly into portal vein
Digestive system
Spleen
Pancreas
Come back to
Hepatic first pass
Portal circulation
What do all blood vessels have apart from capillaries
Smooth muscle
Influenced by autonomic nervous system
What influence do 2 parts of nervous system have on BV’s
Sympathetic - vasoconstriction
Parasympathetic- little influence
What does dilation do to blood pressure
Reduces it
What does construction do to blood pressure
Increases it
Why does sympathetic NS cause vasoconstriction
Fight flight
To pump things around fast
Which substances are exchanged at capillary level and how
Water - osmosis
Nutrients- facilitated diffusion/active transport
Gases - diffusion (internal respiration)
How big is your heart
As big as your fist
How many times does it beat each day/in a lifetime
100,000 per day
2.5 billion in lifetime
How many gallons of blood will the heart pump through how many miles of blood vessels
100,000 million gallons of blood
60,000 miles blood vessels
Location of heart
Mediastinum in thoracic cavity
Apex of heart where
5th intercostal space
4 layers of heart
Pericardium
Epicardium
Myocardium
Endocardium
Define pericardium
Thin double layered sac encloses heart
Serous fluid in between
Describe epicardium
Contains blood lymphatic vessels
Describe myocardium
Main cardiac muscle
Pumps heart
Describe endocardium
Endothelium- smooth surface for heart chambers
Why is serous fluid in pericardium important
Lubricates constantly rubbing surfaces
Heart constantly moving
Movement of blood between atrium, centrioles, lungs and body
From lungs to L atrium to L ventricle to The body to R atrium to R ventricle To lungs To L atrium
How is the R/L of the heart when looking at a diagram
reversed
Right atrium - what type blood, from where, to where
DEOXYGENATED
from Vena Cava to Right Ventricle
Right Ventricle - type blood, from where to where VIA
DEOXYGENATED
from R Atrium to Lungs for oxygenation
VIA pulmonary arteries
Left atrium - type blood, from where to where
Oxygenated
From Lungs via pulmonary veins to Left ventricle
left ventricle - type blood from where to where
From left atrium
oxygenated
round body
how much blood is taken out of left ventricle to supply heart
5%
Compare muscle thickness in L&R Atriums & Ventricles
Ventricles thicker than atria
L ventricle thicker than R
Which are the only red veins in the body as oxygenated
pulmonary
Name 4 heart valves - bi/tricuspid
Mitral - Bicuspid
Tricuspid
Aortic - Tri
Pulmonary - Tri
Where is mitral Valve
Biscupid, between left atrium and left ventricle
where is Aortic valve
tricuspid - between left ventricle and aorta
where is tricuspid valve
tricuspid - between right ventricle & right atrium
where is pulmonary valve
tricuspid - between right ventricle and pulmonary artery
Unique structure of Myocardium
autorythmic smooth cardiac muscle
involuntary
intercalating discs
What type of BV would they use for a coronary bypass and why
Vein - more replaceable, lesser side effects than using an artery
