Circulatory system Flashcards
Blood functions
- Transport of gases, nutrients, and waste products
- Transport of molecules
- Transport of regulatory molecules
- regulation of pH, osmosis, and body temperature
- Protection
- Clot formation
Plasma
liquid matrix that contrains blood cells and other things being transported
formed elements
cells in the blood stream
Plasma elements
proteins, ions, nutrients, waste products, gases, hormones, and water
Formed elements elements
platelets, white blood cells, red blood cells
Plasma proteins
albumin, globulins, and fibrinogen
Albumin
prevents fluid from leaking out of blood vessels
globulins
part of the immune system and transport molecules
Fibrinogen
a clotting factor
Serum
plasma without clotting factors
Serum
plasma without clotting factors
Hematopoiesis
the process that produces formed elements
Red blood cell making
- Hematopoietic stem cell
- Myeloid stem cell
- Proerythroblast
- Early erythroblast
- Intermediate erythroblast
- late erythroblast
- Reticulocyte
- Red blood cell
Red blood cells
the most abundant substance in the formed elements that transports oxygen and carbon dioxide
Red blood cells shape
biconcave disk that increases surface area for more gas exchange they can also decrease in size to more easily pass through capillaries
Capillaries
where red blood cells exchange gases
Hemoglobin
a red protein that binds to oxygen and co2 for transport in red blood cells
Oxygen transport
- O2 enters red blood cell
2.
Hemoglobin structure
Four protein chains called globin are each bound to one heme group. Each heme contains one iron atom which attaches to O2.
Red blood cell colour
When hemoglobin is bound to O2 it is bright red. When it does not have oxygen it is a dark red.
Carbonic anhydrase
an enzyme found in red blood cells that catalyzes the reaction between carbon dioxide and water to create bicarbonate and then the bicarbonate can be transported by the blood
ways of transporting co2
Turing it into bicarbonate, binding it to protiens and dissoliving in plasma
Proerythroblasts
the stem cell that creates red blood cells
When does red blood cells lose their nucleus
during the late erythroblast stage
What signals the creation of red blood cells
low blood O2 levels due to decreased number of red blood cells, lung issues, hemoglobin issues, and issues in blood transport
erythropoietin
a glycoprotein that stimulates red bone marrow to produce more red blood cells
how are red blood cells disposed?
macrophage breaks down hemoglobin > globin is broken into amino acids > iron is released from heme group > heme molecules are converted to bilirubin > bilirubin is excreted
pulmonary circulation
systems of blood vessels that carry blood from the right ventrile to the lungs and back to the left atrium
systemic circulation
blood vessels that carry blood from the left ventrile to the body and back to the right atrium
heart functions
generating blood pressure, routing blood, ensuring one way flow, and regulating blood supply
apex
point of the heart
base
flat end of the heart
pericaridal cavity
heart cavity
pericardium layers
fibrous pericardium (outer layer), serous pericardium (inner layer with two parts(parietal and visceral))
paricardial fluid
thin layer of protective fluid around the heart
Four chambers of the heart
right and left atrium and the right and left ventricle
Artiums
Function as resovoirs for blood before it enters the ventricles. The right recieves blood from the superior vena cava, the inferior vena cava and the coronary sinus
Interatrial septum
separtates the two atriums
Interventricual septum
separates the two ventricles
Atrioventricular valve (AV)
valves that open into the ventrical to prevent blood back flow.
It works by the ventricles contracting causing blood to flow up and the valves to close. When the atrium has higher pressure it opens the valves.
Tricuspid valve
a valve composed of three cusps that open into the right ventricle
bicuspid valve
a valve composed of two cusps that open into the left ventricle
papillary muscles
muscular pillars which the chordae tendineae attach
Chordae tendineae
heart strings that open and close the AV when the ventricles contract
Semilunar valve
one of two valves that prevent blood flow into the ventricles following ejection
pulmonary semilunar valve
valve that prevents backflow into the right ventricle
aortic semilunar valve
valve that prevents backflow into the left ventricle
cardiac skeleton
fibrous rings that surround the vavlues and give them support
Route of blood flow in the heart
Deoxygenated blood enters right atrium from the superior and inferior vena cava > blood goes through the tricupid valve into the right ventricle > right atrial contracts and causes the right ventricle to also contract > blood flows to lungs > Blood is oxygenated > Blood enters the left atrium > left atrium contracts causing the left ventricle to also contract > blood leaves via aorta.
coronary arteries
supply the heart with blood
heart wall composition
Epicardium (outersurface)
myocardium (middle layer) - contractions
Endocardium (innerlayer) - blood to heart
Trabeculae carneae
cardiac muscle iin the ventricles of the inner layer
Heart signaling
- Heart is at rest
- Cardiac muscles are stimulated by action potentionals
- cardiac muscles in the artial contract
- cardiac muscles in the ventrical are stimulated second
- cardiac muscles in the ventrical contract
action potental of skeletal muscle
a very quick depolarization that causes a spike in tension
action potental of cardiac muscle
quick depolarization followed by a plateau that causes elongated tension
Path way of action potentials
- SA node sends a signal to the left and right atrium causing a contraction and the AV node
- AV node spreads the action potential through the AV bundle
- The AV bundles become Purkinje fibers and extend to the ventricle walls causing a contraction
Ectopic beat
when something other then the SA node starts the action potential
fibrillation
a condition that causes irregular heart beat due to ectopic beats
electrocardiogram
a recording to the action potentials of a heart
cardiac cycle
repetitive pumping of the heart
1. blood flows into atria
2. atiral systole causes atrium to contract
3. Verticular systole contraction pushes blood towards the atrium causing the valves to close
4. increasing pressure pushes blood out of the heart
5. ventricular diastole relaxes the heart.
cardiac cycle
repetitive pumping of the heart
1. blood flows into atria
2. atiral systole causes atrium to contract
3. Verticular systole contraction pushes blood towards the atrium causing the valves to close
4. increasing pressure pushes blood out of the heart
5. ventricular diastole relaxes the heart.
Circulatory system functions
carry blood, transport, regulate blood pressure, blood flow to tissues, exchange
pulmonary vessels
vessels that carry blood to the lungs
systemic vessels
transport blood to the body
capillaries
where nutrient and gas exchange occur
Veins
carries blood towards the heart after gas exchange and contain valves to prevent blood back flow
tunica intima
inner layer of blood vessles
Tunica media
middle layer of blood vessles
tunica adventitia
the outer dense layer of blood vessels
Elastic Arteries
the largest arteries with the thickest walls that stretch from blood pressure
Muscular arteries
control blood flow to different regions of the body.
Vasoconstriction
contraction of the muscular arteries to decrease blood flow
Vasodilation
muscular arteries relax to increase blood flow
arteries
carry blood away from the heart
Arterioles
takes the blood to the capillaries and only have one or two layers
precapillary sphincters
smoother muscles that can cut off blood flow to certrain capillary routes
Vennules
the smallest veins that attach to capillaries
Blood pressure
the force of blood against the blood vessel walls
Systolic pressure
the maximum value of blood pressure
diastolic pressure
the minimal value of blood pressure
Baroreceptor reflex
A decrease in blood pressure is snesed by the baroreceptors. Signal is sent to the medulla. sympathetic division increases heart rate. Epinephrine cuase vessel constriction
