Chapter 19 - Cardiovascular System - Blood Flashcards
**Blood **
liquid connective tissue consisting of cells surrounded by liquid extracellular matrix **(blood plasma) **
(3) general functions of blood
transportation
regulation
protection
(2) components of blood
1) blood plasma
2) formed elements (cells & cell fragments)
blood plasma
watery liquid extracellular matrix
**Blood Plasma **is made up of?
91.5% water, 8.5% solutes (primarily proteins)
What synthesizes most plasma proteins?
Hepatocytes
Types of Plasma Proteins
Albumins (54%)
fibrinogen
antibodies
globulins (38%)
(3) components of formed elements of blood
1) red blood cells
2) white blood cells
3) platelets
**Red Blood Cells (erythrocytes) **
contain?
production = ?
shape?
consist of?
lack?
contain **hemoglobin - **oxygen-carrying protein
production **= destruction **(2 million new RBCs/second)
biconcave disk (increases surface area)
glycolipids in PM responsible for ABO & Rh blood groups
no nucleus or mitochondria
Hemoglobin
made of?
**Heme - **ring like nonprotein pigment
- 1 in each of 4 chains
**Globin - **4 polypeptide chains
Hemoglobin & Iron
iron ion at center of heme ring can combine reversibly with one oxygen molecule
What can bind to hemoglobin?
Oxygen, Carbon Dioxide & Nitric Oxide (NO)
release of nitric oxide from hemoglobin causes?
**vasodilation **- increase in blood vessel diameter
to improve blood flow & oxygen delivery
RBCs live ___ days
synthesis?
120 days
cannot synthesize new components - no nucleus or other organelles
What happens to ruptured blood cells?
Ruptured red blood cells removed from circulation & destroyed by fixed
phagocytic macrophages in spleen and liver
**Recycling Process **of Blood cells
1) macrophages phagocytize ruptured RBCs (in spleen, liver or red bone marrow)
2) globin & heme portions are split
3) globin is broken down to amino acids - used to make proteins
4) Iron is removed from heme in form of FE(3+) & ends as yellow pigment **urobilin **in urine or brown pigment **stercobilin **in feces
**White Blood Cells **
have?
lack?
have nuclei
lack hemoglobin
Types of WBCs
1) Granular
2) Agranular
Granular **Leukocytes **(WBCs)
- types (3)
neutrophils
eosinophils
basophils
Agranular **Leukocytes **(WBCs)
- types (2)
lymphocytes
monocytes
WBCs live for ___ days except for ___ which live?
a few days except **lymphocytes **which live for months or years
Leukocytosis
normal protective response to invaders, strenuous
exercise, anesthesia and surgery
Leukopenia
abnormally low level of WBCs
Which **WBCs **are active phagocytes?
attracted by?
**Neutrophils **and **marophages **
chemotaxis
______________respond most quickly to tissue damage by bacteria
Neutrophils
- release lysozymes & strong oxidants & defensins (antibiotic activity)
______________take longer to arrive but arrive in larger numbers and destroy more microbes
Enlarge & differentiate into ___?
Monocytes
Macrophages
**Basophils **function
leave capillaries and release granules containing heparin,
histamine and serotonin, at sites of inflammation.
- involved in inflammatory reaction & allergies
**Eosinophils **function
leave capillaries and enter tissue fluid & release enzymes
phagocytize antigen-antibody complexes
effective against parasitic worms
Lymphocytes
types? (3)
major soldiers of the immune system
B cells
T cells
Natural Killer (NK) cells
destroy bacteria & inactivate their toxins
B Cells
attack viruses, fungi, transplanted cells, cancer cells and some bacteria
T cells
– attack a wide variety of infectious microbes and
certain tumor cells
Natural Killer (NK) cells
Origin of blood cells
pluripotent stem cell
1) myeloid + 2) lymphoid stem cells
1) RBCs, platelets, granular WBCs & monocytes
2) Agranular WBCs (except monocytes)
**Platelets **- production
**myeloid stem cell **–> **megakaryoblasts **–> **megakaryocyte –> platelets **
Platelets (thrombocytes)
shape?
function?
life span?
fragment of megakaryocyte enclosed by piece of PM
- disc-shaped with many vesicles but no nucleus
promote blood clotting & help stop blood loss from damaged blood vessels
5-9 days
Heart
located in?
**mediastinum - **region extending from sternum to vertebral column, 1st rib & between lungs
Heart
1) **apex **
2) base
3) anterior surface
4) inferior surface
5) right border
6) left border
1) tip of left ventricle
2) posterior surface
3) deep to sternum & ribs
4) b/w apex & right border
5) faces right lung
6) pulmonary border - faces left lung
Pericardium
**- (2) **main parts
Membrane surrounding and protecting the heart
1) fibrous pericardium
2) serous pericardium
a) parietal layer
b) visceral layer (epicardium)
Layers of Heart Wall
Epicardium (visceral layer of serous pericardium)
Myocardium - cardiac muscle
**Endocardium - **smooth lining
Chambers of the Heart
**2 Atria - **recieving chambers
- **auricles **on anterior surface
**2 Ventricles - **pumping chambers
Sulci
series of grooves of heart surfacce that contain coronary blood vessels & fat
marks boundary between 2 chambers of the heart
Coronary sulcus
marks boundary between superior **atria **& inferior ventricles
1) Anterior interventricular sulcus
2) Posterior interventricular sulcus
1) between left & right ventricle on anterior surface
2) between ventricles on posterior surface
**Right Atrium **
forms ___ ___
recieves blood from (3) veins
right border
1) superior vena cava
2) inferior vena cava
3) coronary sinus
Interatrial septum
- prominent feature?
between atria
fossa ovalis - oval depression
Blood passes through ______________valve into
right ventricle from right atrium
** tricuspid valve (right atrioventricular valve)**
Right Ventricle
forms?
inside contains?
anterior surface of heart
trabeculae carneae - ridges formed by raised bundles of
cardiac muscle fiber
Tricuspid Valve is connected to __ ___ which is connected to __ ___
chordae tendinae
**papillary muscles **
Blood flow:
right atrium –> (tricuspid valve) –> right ventricle —> ____ –> ___ ___ –> ___ ___
from right ventricle through **pulmonary valve **into pulmonary trunk & then to right & left pulmonary arteries –> lungs
**Left Atrium **
recieves blood from __ through ___ veins
passes through ___ valve into ____ ___
lungs through 4 **pulmonary veins **
**bicuspid/mitral/left atrioventricular valve **into left ventricle
Left Ventricle
- thickness?
forms?
blood passes from left ventricle through _ __ ( __ ___ valve) into __ __
aortic valve (aortic semilunar valve) –> ascending aorta
some blood flows into **coronary arteries, **remainder to body
** Myocardial thickness **
atria vs ventricles
atria walls are thinner - deliver blood under less pressure to ventricles
Distance, Pressure & Resistance for each:
1) Right ventricle pumps blood to ______________
2) Left ventricle pumps blood to ______________
Left ventricle works ___ to maintain same rate of blood flow as right ventriclw
1) LUNGS
Shorter distance, lower pressure, less resistance
2) all other parts of body
* *Longer** distance, higher pressure, more resistance
harder
Heart wall also contains fibrous skeleton
Dense connective tissue that forms a structural foundation, point of insertion
for muscle bundles, and electrical insulator between atria and ventricles
Atrioventricular valves (2)
- located between an atrium & a ventricle
tricuspid & bicuspid valves
Atria contracts/ ventricle relaxed
AV valves open, cusps project into ventricle
blood moves from **atria (higher pressure) **to **ventricles (lower pressure) **through AV valves
SL valves closed
Atria relaxed/ ventricle contracts
AV valves close
SL valves open
No valves guarding entrance to __?
**right atrium **from venae cavae
** left atrium** from pulmonary veins
Systemic Circuit
left side of heart
recieves blood from lungs –> aorta –>
**systemic arteries –> systemic arterioles **–> systemic capillaries (gas & nutrient exchange)
–> systemic venule –> systemic **veins –> **right atrium
Pulmonary Circuit
right side of heaert
recieves blood from **systemic circulation **
-> pulmonary trunk -> pulmonary **arteries -> pulmonary capilla**ries -> pulmonary veins -> left atrium
Systemic vs. Pulmonary Circulations
**gas exchange in capillaries **
**Systemic - **unloads O2, picks up CO2
**Pulmonary - **unloads CO2, picks up O2
CORONARY CIRCULATION
myocardium has its own network of blood vessels
ascending aorta → coronary a. (*encircle heart) *→ capillaries → coronary v.
**Coronary arteries **that branch from ascending aorta
supply oxygenated blood to myocardium
**LEFT: **
**a) **anterior interventricular - ventricles
b) circumflex branches - left ventricle/atrium
**RIGHT: **
(small branches to right atrium)
a) posterior interventricular - ventricles
b) marginal - right ventricle
Coronary Veins
blood passes through arteries of coronary circulation → capillaries → coronary veins
drains into **coronary sinus **→ right atrium
(4) veins carry blood into Coronary Sinus
1) great cardiac vein
2) middle cardiac vein
3) small cardiac vein
4) anterior cardiac vein
Histology of Cardiac Muscle Tissue
__ and less __ than skeletal muscle fibers
structure?
organelles?
shorter & less circular
branching - stair-step appearance
one central nucleus
mitochondria are larger & more numerous than in skeletal muscle
ends of fibers connected by **intercalated discs **that contain:
desmosomes - hold fibers together
& **gap junctions - **allow muscle action potential conduction b/w fibers
Autorhythmic Fibers
(2) functions
Specialized cardiac muscle fibers- source of electrical activity causing heart beart
- self-excitable
repeatedly generate action potentials that trigger heart contractions
1) PACEMAKER
2) CARDIAC CONDUCTION SYSTEM
Ausculatation
act of listening to sounds within the body
Sound of heartbeat comes primarily from..? caused by?
blood turbulence caused by closing of heart valves
4 heart sounds in each cardiac cycle
– only 2 loud enough to be heard
S1: Lubb – AV valves close
S2: Dupp – SL valves close
5 main types of blood vessels
arteries - (blood away from heart)
arterioles
capillaries
venules
veins
(3) layers in blood vessels
Tunica interna
tunica media
tunica externa
Tunica Interna
inner lining in contact with blood
endothelium continuous with endocardial lining of heart
Tunica Media
muscular & connective tissue layer
Smooth muscle regulates diameter of lumen
Tunica Externa
elastic & collagen fibers
**vaso vasorum - **vessels that supply blood to vessel wall
anchors vessels to surrounding tissue
Arteries - (3) layers
thick muscular/elastic **tunica media **
high **compliance **(stretch)
Elastic Arteries
largest
thin walls
pressure reservoir
help propel blood forward while ventricles relaxed
aka **conducting arteries **- conduct blood to medium sized arteries
Muscular arteries
medium sized
**Tunica media - **more smooth muscle than elastic fibers
thick walls
adjust rate of blood flow (constrict/dilate)
aka **distributing arteries **
Anastomis
union of branches of 2 or more arteries supplying same body region
**Arteries of upper limb **
which artery passes between clavicle and 1st rib
subclavian
Subclavin artery → ??
→ axillary →brachial →radial →ulnar
Which artery is used for:
a) blood pressure
b) pulse
a) brachial
b) radial
Arterioles
____ has s precapillary sphincter which monitors blood flow into capillary
metarteriole (terminal end)
play key role in regulating blood flow into capillaries by regulating resistance
Capillaries
function?
smallest blood vessels
connect arterial outflow & venous return
- exchange bwtween blood & interstitial fluid
- lack tunica media & externa
(2) ways for blood to flow from arteriole into venule
1) capillaries
2) throughfare channel
3 types of capillaries
continuous
fenestrated
sinusoids
continuous capillaries
Endothelial cell membranes from continuous tube
- CNS, lungs, skin & muscle tissue
Fenestrated capillaries
Have fenestrations or pores
- kidney, villi of smalll intestine, choroid plexuses in brain ventricles, ciliary processes &endocrine glands
Sinusoids
Wider and more winding
Unusually large fenestrations
Portal vein –
blood passes from capillary network into another
Venules
Thinner walls than arterial counterparts
Postcapillary venule – smallest venule
Form part of microcirculatory exchange unit with capillaries
Muscular venules have thicker walls with 1 or 2 layers of smooth muscle
Veins
contain?
thin walls
thinner tunica interna -
**tunica media - **little smooth muscle
tunica **externa - **thickest layer
CONTAIN VALVES
Largest portion of blood at rest is in ?
systemic veins and venules
Capillary Exchange
movement of substances between blood & interstitial fluid
Substances enter & leave capillaries by (3) mechanisms
1) diffusion
2) transcytosis
3) bulk flow
Besides the heart, (2) other mechanisms pump blood from lower body to heart
1) skeletal muscle pump
2) respiratory pump
skeletal muscle pump
contraction → compressed vein →milking (pushes blood through proximal valve) & distal valve closes
muscle relaxation → proximal valve closes → distal valve opens → proximal valve reopens
Respiratory pump
based on alternating compression & decompression of veins
Inhalation → thoracic cavity pressure decreases → abdominal cavity pressure increases →abdominal veins compressed → blood moves to thoracic veins → right atrium
Exhalation → valves in veins prevent backflow from thoracic to abdominal veins
(3) types of sensory receptors that provide input to cardiovascular center
**Proprioceptors **– monitor movements of joints and muscles to provide input during physical activity
**Baroreceptors **– monitor pressure changes and stretch in blood vessel walls
**Chemoreceptors **– monitor concentration of various chemicals in the blood
