The Circulatory System Flashcards by Enrique de la Rosa

Vaso que llega al corazón

Vena

How well did you know this?

Not at all

Perfectly

Todos llegan al corazón, no se llaman venas ya que no transportan sangre, transportan linfa que al final desemboca en el sistema venoso

Vasos linfáticos

How well did you know this?

Not at all

Perfectly

Dos tipos de sistema circulatorio

Sistema circulatorio menor

Sistema circulatorio mayor

How well did you know this?

Not at all

Perfectly

Es la que existe entre el corazón y los pulmones, cuando se lleva la sangre a oxigenar

Circulación menor

How well did you know this?

Not at all

Perfectly

Vaso que sale del corazón

Arteria

How well did you know this?

Not at all

Perfectly

es la que existe entre el corazón y el resto del cuerpo y sus sistemas

Circulación mayor o periférico

How well did you know this?

Not at all

Perfectly

Tres capas del corazón

Epicardio
Miocardio
Endocardio

How well did you know this?

Not at all

Perfectly

La mas externa , llamado pericardio visceral, formada por tejido conectivo laxo, presenta fibras de colageno es el sitio donde se acumula el tejido adiposo que recubre al corazón,que puede ser muy extenso

Epicardio

How well did you know this?

Not at all

Perfectly

Es propiamente el músculo encargado de la contracción y bombeo del corazón , formada por las células de músculo estriado cardiaco, en haces de fibras en forma de espiral.

Miocardio

How well did you know this?

Not at all

Perfectly

Capa mas interna, está formado por un epitelio de tipo plano simple sobre una lamina basal, asentados ambos sobre una capa subendotelial de fibras de colagena, fibroblastos y algunas fibras escasas del músculo liso

Endocardio

How well did you know this?

Not at all

Perfectly

La víscera cardiaca se encuentra dentro de una bolsa conocida como…, parietal formado por células mesoteliales y tejido conectivo,

Pericardio

How well did you know this?

Not at all

Perfectly

El pericardio en su interior cuenta con

Abundante tejido adiposo, y pequeñas cantidades de líquido para lubricar al corazón durante su movimiento

How well did you know this?

Not at all

Perfectly

Estructura funcional mas importante del sistema circulatorio

Capilar

How well did you know this?

Not at all

Perfectly

Diámetro del capilar

5-7 micrómetros, que el eritrocito tiene mayor contacto con la pared vascular y aquí libera oxigeno y recoge el dióxido y monóxido de carbono.

How well did you know this?

Not at all

Perfectly

Máximo Diámetro de la aorta

3 centímetros

How well did you know this?

Not at all

Perfectly

Órgano formado por fibras elásticas , en su interior esta revestido por un epitelio plano simple, endotelio

Aorta

How well did you know this?

Not at all

Perfectly

La capa elástica se va perdiendo conforme se aleja del corazón y son sustituidos por

Músculo liso el cual va a regular la presión dentro del vaso

How well did you know this?

Not at all

Perfectly

Son un tipo de capilar que tiene tres características
Células endoteliales discontinuas
Células endoteliales suelen estar fenestradas
Hay macrofagos en contacto con la luz al mismo nivel que las células endoteliales

Sinusoides

How well did you know this?

Not at all

Perfectly

Los vasos sanguíneos están formados por 3 capas

Túnica intima
Túnica media
Túnica adventicia

How well did you know this?

Not at all

Perfectly

Capa cuyos componentes son un revestimiento de endotelio especializado, tejido conectivo subendotelial y una lamina generalmente fenestrada de tejido elástico

Túnica intima

How well did you know this?

Not at all

Perfectly

Capa formada por células de músculo liso acomodados en forma espiral o circular y fibras reticulares y elásticas dispersas

Túnica media

How well did you know this?

Not at all

Perfectly

Capa formada por una lamina elástica externa irregular y tejido conectivo elástico y fibras de colagena distribuidas principalmente en forma longitudinal

Túnica adventicia

How well did you know this?

Not at all

Perfectly

Son vasos sanguíneos revestidos por un endotelio , por donde las células linfoides , pueden escurrirse por un proceso llamado transmigración, no se observa capa elástica pero si un sistema de fibras elásticas a lo largo de su pared, muchas cuentan con válvulas que son proyecciones de la capa intima y toman forma bicuspidea

Venas

How well did you know this?

Not at all

Perfectly

Proceso por donde las células linfoides(celulas blancas de la sangre) pueden escurrirse y pasar al tejido para llevar acabo su función

Transmigración y diapedesis

How well did you know this?

Not at all

Perfectly

Características de las arterias

``` Forma redondeada, menos deformada Pared gruesa Capa intima arrugada Tiene tres capas(túnica media prominente) Cuenta con una lamina interna elástica ```

Características de las venas

``` Plana Pared delgada Capa intima lisa No se pueden diferenciar las tres capas No tiene elástica interna ```

Vaso principal

La aorta

La manera de distinguirlos es que son en realidad un espacio en blanco con una célula basofila y alargada en un extremo

Capilares

Adult total vessels length is estimated at between

100,000 and 150,000 kilimeters

Propel blood through the system

Heart

Series of vessels efferent from the heart that become smaller as they branch into various organs, carry blood to the tissue

Arteries

The smallest vessels , are sites of O2,CO2, nutrients, and waste product exchange between blood and tissue

Capillaries

Complex network of thin, anastomosing tubules called

Microvasculature

Propel blood to the pulmonary and systemic circulation

Right and left ventricles

When the body is at rest ..% of the blood moves through the systemic circulation

70%

When the body is at rest ..% of the blood moves through the pulmonary circulation

18%

When the body is at rest ..% of the blood moves through the heart

12%

Myocardium is much thicker in the wall of the ventricles, particularly

The left

Flaps of connective tissue anchored in the heart's dense connective tissue or cardiac skeleton

Valves

Cords that extended from the cusps of both atrioventricular valves and attach to papillary muscle

Chordae tendineae

Valves and cords are covered by the

Nonthrombogenic endothelium

Functions of cardiac skeleton

Anchoring and supporting the heart valves Providing firm points of insertion for cardiac muscle Helping coordinate the heartbeat by acting as electrical insulation between atria and ventricles

Located in the right atrial wall, also called pacemaker, is a 6 to 7mm3 mass of cardiac muscle cells with small size, fewer myofibrils and fewer typical intercalated disks

Sinoatrial SA node

Located in the floor of the right atrium, they stimulate depolarization

Atrioventricular AV node

The AV node is continuous with specialized bundles of cardiac muscle fibers the....,

AV bundles or His

The AV node is continuous with specialized bundles of cardiac muscle fibers the AV bundles (of His), that run along the interventricular septum to the apex of the heart, where they branch further as ...., that extend into myocardium of the ventricles

Conducting (Purkinje) fibers

Subendocardial conducting network of myofibers usually called ...

Purkinje fibers

These are pale staining fibers, larger than the adjacent contractile muscle fibers, with sparse, peripheral myofibrils and much glycogen

Purkinje fibers

Slow the heartbeat

Parasympathetic division (vagus nerve)

Accelerates activity of the pacemaker

Sympathetic nerve

Occurs when partially occluded coronary arteries cause local oxygen deprivation

Angina pectoris

Abnormalities in the structure of heart valves, produces An abnormal heart sound referred to as

Heart murmur

Wall of all blood vessels except capillaries contain

Smooth muscle | Connective tissue

Endothelium presents ..., on which blood will not clot and actively secrets agents that control local clot formation

Nonthrombotic surface

Endothelium presents nonthrombotic surface on which blood will not clot and actively secrets agents that control local clot formation such as

Heparin Tissue plasminogen activator Von Willebrand factor

The endothelial cell regulate local vascular tone and blood flow by secreting various factors that stimulate smooth muscle contraction such as

Endothelin 1 | Angiotensin converting enzyme ACE

The cell endothelial regulate local vascular tone and blood flow by secreting various factors that stimulate smooth muscle relaxation such as

Nitric oxide | Prostcyclin

Endothelium has several roles in inflammation and local immune responses, ..... Is expressed rapidly on the luminal surface when enlongated granules called Weibel Palade bodies fuse with the cell membrane

P selectin

Endothelium cells secret factors that affect the activity of local white blood cells during inflammation

Interleukins

Stimulate vasculogenesis

Vascular endothelial growth factor VEGF

Promote capillary sprouting and out growth from small existing vessels (angogenesis)

Vascular endothelial growth factor VEGF

Stimulates endothelial cells to recruit smooth muscle cells and fibroblasts to form the other tissues of the vascular wall

Angiopoietins

Release factors that initiate a cascade of events that produce fibrin from circulating plasma fibrinogen

Platelets

A fibrin framework quickly forms to stop blood loss from the damaged vessels

Thrombus

From large thrombi, solid masses may detach and be carried by the blood to obstruct distant vessels

Emboli

Individuals in the initial stages of medical conditions involving thrombus formation such as myocardial infarct, stroke, or pulmonary embolism are treated with

Tissue plasminogen activator or tPA , this is a serine protease that breaks down fibrin and quickly dissolves the clot

Are connected by gap junctions and permit vasoconstriction and vasodilatation

Smooth muscle cells

Are found in the subendotelial layer, between the smooth muscle layers and in the outer covering

Collagen fibers

Provide the resiliency required for the vascular wall to expand under pressure

Elastin fibers

Contribute to the physical and metabolic properties of the wall in different vessels affecting permeability

Proteoglycans | Hyaluronate

Consist of the endothelium and thin subendothelial layer of loose connective tissue

Intima

In arteries and large veins, the intima includes a limiting layer

The internal elastic lamina composed of elastin with holes allowing better diffusion of substances from blood deeper into the wall

Consist of concentric layers of helically arranged smooth muscle cells, interposed among the muscle fibers are amount of elastic lamellae , reticular fibers and proteoglycans produced by smooth muscle cells

Tunica media

In arteries the media have

A thin external elastic lamina separating the externa tunic

Consist principally of type I collagen and elastic fibers , and is continuous with the stromal connective tissue

Adventitia

Arteries, venules, capillaries in the adventitia

Vasa vasorum

Have more vasa vasorum than arteries because carry desoxigenated blood

Large veins

The adventitia of larger vessels contains a network of autonomic nerves fibers ..., which release the vasoconstrictor Norepinephrine

Vasomotor nerves

Examples of elastic arteries

Aorta, pulmonary artery and their largest branches

Also called conducting arteries

Elastic arteries

The most prominent feature of elastic arteries is the thick media each about

10 micrometers alternate with layers of smooth muscle fibers

Important function of elastic arteries

Making blood flow more uniform

Ventricular contraction

Systole

Verticles relax

Diastole

Disease of elastic arteries and large muscular arteries , initiated by damaged or dysfunctional endothelial cells oxidizing LDLs in the tunica intima induces adhesion and intima entry of monocytes/macrophage to remove the modify LDLs

Atherosclerosis

Lipid filled macrophage accumulate and produce a pathologic sign of early atherosclerosis called fatty streaks

Foam streaks

Fibro fatty plaques, Consisting of a gruel like mix of smooth muscle cells, collagen fibers, and lymphocytes with necrotic regions of lipid,debris and foem cells

Atheromas

Predisposing factors in atherosclerosis

Dyslipidemia Hyperglycemia of diabetes Hypertension

In elastic arteries atheromas produce localized destruction within the wall, weakening in and causing arterial bulges called

Aneurysms

Slight dilations of the bilateral internal carotid arteries where they branch from the elastic common carotid arteries, acts as baroreceptors

Carotid sinuses

At sinuses this layer is thinner allowing greater distention when blood pressure rises

Media layer

Contains many sensory nerve endings from craneal nerve IX(glosopharyngeal)

Adventitia

Monitors blood levels of CO2 and O2 as well as hydrogen concentration pH

Chemoreceptors

Chemoreceptors are found in

Carotid bodies | Aortic bodies located in the wall of the carotid sinuses and aortic archivo

Carotid bodies and aortic bodies are parts of the autonomic nervous system called

Paraganglia with rich capillary network

Paraganglia capillary network are surrounded by glomus type I cells filled with dense core vesicles containing

Dopamine Acetylcholine And others which are supported by small satélite type II cells

Appropriate ion channels in the glomus cell membranes respond to stimuli in

The arteria blood Hypoxia low O2 Hypercapnia excess CO2 Acidosis

Glosopharyngeal nerve form sinapses with the glomus cells and signal brain center to initiate

Cardiovascular and respiratory adjustments that correct the condition

Distribute blood to the organs and help regulate blood pressure by contracting or relaxing smooth muscle in the media, the intima has a thin endothelial layer and prominent internal elastic lámina, media contains up to 40 layers of large smooth muscle and external elastic lámina, and adventitia only connective tissue with vasa vasorum and lymphatic capillaries

Muscle arteries

Outer diameter of muscle arteries

10 - 1 mm

Outer diameter of An small arteries

1.0- 1 mm

Intima layer only endothelium, 3-10 layers of smooth muscle in media and adventitia only connective tissue without vasa vasorum and his function is to distribute blood to arterioles adjusting flow with vasodilatation and constriction

Small arteries

Size of 1or 2,of media layers of smooth muscle indicating organ's microvasculature where exchanges occurs, subendotelial layer thin, elastic lamina absent and media Consist of the circularly arranged smooth muscle cells

Arterioles

Arterioles outer diameter

Less than 0.1 mm

The major determinants of systemic blood pressure

Arterioles

Elevated blood pressure secundarily to renal or endocrine problems increase of arteriolar constriction

Hypertension

Microvascular pathways in which blood flows through two successive capillary bed separated by a portal vein

Portal system

Arterioles supplying a capillary bed typically form smaller branches called

Metarterioles in which smooth muscle cells are dispersed as bands that act as precapillary sphinters

Distal portion of metarteriole called..., lack smooth muscle and merges with poscapillary venules

Throughfare channel

Examples of portal system

Hypothalmic hypophyseal | Hepatic portal

The precapillary sphinters that contract and relax to control the entry of blood, a cycle with.....cylces per minute

5 to 10 cylces per minute

Diameter of a capillaries and their length

From 4 to 10 micrometers diameter | More than 50 micrometer