Part 1 Flashcards
بسم الله الرحمن الرحيم وبه نستعين
إن الله هو الرزاق ذو القوة المتين
توكلنا علي الحي الذي لايموت
Fucntions of CVS?
1-Homeostsis
2-Temperature Regulation
3-Communication
The ultra important funvtion ? keeping adequate blood perfusion to Capillaries Overall the body
قوانين الانسياب في الدوري؟
الدم دايما بيتجه اتجاه واحد في دائرة مغلقة Fluidity Continuity Circuity Unidirectional
اهمية توصيل الدم بالتوازي للأعضاء؟
نفس مكونات الدم الطازج
الدم المنساب لعضو واحد ممكن تتحكم فيه وحده
أقل مقاومة طرفية
Homeostasis how occure?
Maintain intersistial fluid compnents in reguler portions
By:
Pumping Heart
Conditioning of Blood as it passes throug Other organs as lungs and liver and kideny @@
Communcation Of CVS?
By Endocrinal hormones modulating functions of all body through blood
The heart is dual pump ?
Compression in systole
Suction in diastole
Aorta and big arteries and Windkessel ?
Aorta can act as Pressure store accepting more blood soting the excess pressure and expansion of wall during systole then it recolis during diastole to make the stored pressure flow downstream
Musclar arteries?
Delvring arteries low resistance
Arterioles resistance Function
High rssistance and sphincteric as stopcocks that maintain arterial blood pressure and blood flow to tissues
Main effector on the peripheral resistance and blood pressure
Veins (Capacitance Functions)
Venous retuen also CVS reseroir of blood due to capacitance
Types of flow ?
Intermittent from ventricles into the aorta only pump during systole and stop during diastole
Pulsatile in aorta due to Windkessel phenomenon leading to high systole low diastole
Still pulsatile in capillaries with little difference between systole and diastole
Pulstatily disappear in veins the flow is steady
Seires and parllel
Systemic + pulmonary
the branches to the tissues of organs in parallel as to brain - skeletal muscles - kideny -heart
مميزات التوصيل علي التوازي؟
- HOMEOSTASIS
- Control of An organ blood flow separately
- Decreasing TPR
High pressure sysytem ?
Left ventricle during systole
Aorta big aterires muscular arteries
arterioles
Arterial end of capillary proximal to dividing point
Low pressure system
Venous end of capillaries distal to the divifing point
Venules small veins big veins venea Cavae
Right and Left atrium
Pulmonaru circulation as a whole
right and left ventrivle during diasrole
علاقة عكسية بين السرعة والمساحة الكلية المقطعية
كلما صغر مقطع الوعاء كثرت اعداده بمعني
الاورطي عملاق مفيش منه الا واحد فمسحاة المقطع نسبيا صغيرة ل
ان الشعيرات الدموية صغيرة عدد كبير جدا جدا جدا مساحة المقطع الكلية اكبر من الاورطي
فالسرعة فيها اقل من الاورطي وهذا مايسمح بتبادل الغازات
Artery
Capillary
Vein
Velocity
50cm/s
1mm/s capillary
30cm/s
Distensibility =Capacity
حجم الدم المحمول علي في اي جزء من الدوري في لحظة
Volume change per unit change in pressure
the functional capillary pressure ?
the pressure of the dividing point on mid ot the capillary = 17mm Hg
V=Q/A
Q flow direct proprtional
A inversely
الحمدلله رب العالمين
A-V Ring act as ?
Cardiac Skeletion
electrice insulator
Papillary muscles role?
تنقبض مع انقباض عضلة القلب اثناء السيستول
وتمسك في الصمام وشرفاته تمنع انها تتفتح ناحية الاذين بسبب الضغط العالي جوا البطين
Heart is functional syncitum not true one
Gap junctions
One unit
All or none
Functional synctium ?
Gap junctions electrical synctium
Desmosome mechanical synctium
Cardiac muscles are divided into /
Nodal : pacemaer
junctional : conductive
Musclar contractile tissue
Pericardial inelastic or elastic why?
Inelastic pervents cardiac dilatation except in pysiological variations
Pericardial effusin severity?
Cauing increased intrapericardial pressure compressing the heart preventing VR and Ventricular Filling cardiac tamponade
Only connection between atria and ventricles?
Bundle of His
Left ventricular aid
contraction of left ventricle increases pressure in the right ventricle
There are intercalated discs \and desmosmones why?
Intercalated discs areas of low resistance allowing movment of action potenial easily between cardiac cells
Desmosomes helds the muscle cells together
Main 4 proteins for contration ?/
Actin
Myosin
Troponin
Tropomyosin
The Dihydropyrdidine recptors where/
DHP in the T tubules which are voltage gated Ca Channels
The ryanodine recetors where?
In terminal cisternae
Are Ca release Channels
Ca induced Ca Relese ?
CICR ?
This is the release of Ca from the ryanodine receptor of termnal cisrterneae of sarcoplasmic reticulum
due to activation of the DHP dihydopyridine receptors by the ECF Ca entered througth the T-tubule
True synctium =
Prtoplasmic contiunity of cells
Heart is functional synctium ?
Due contraction as a one unit
All or none law following : no gradtion of response in increasing stmulus above the threshold
No protoplamic continuity
Electrical and mechanical synctium of the heart?
Electrical : due to prence of the Gap junctions allowing action poteinal to spread easily between the fibers
Desmosmes: Cohesin between fibers when one fiber contreact attract the olther and is tied with it making the heart contract as a one unit as afully mechanical synctium