Studied by 8 peopleWhat is the heart?
a hollow, muscular organ the size of a fist
where is the heart located?
between the lungs
What is the apex?
the "tip" of the heart
where is the apex pointed?
towards the left hip
what is the outer covering of the heart called?
the pericardium
What is the space between the heart and pericardium called?
the cavity
What is the middle/thickest layer of the inside of the heart called?
myocardium
What is the function of the pericardium?
to protect and lubricate heart while it pumps
why is the myocardium the yhickest layer of the heart?
responsible for pumping the heart, made of muscle
What are the two loops that circulate blood back to the heart?
Pulmonary Circuit
Systemic Circuit
What does the pulmonary circuit do?
it carries blood to the lungs (picks up oxygen and drops carbon dioxide)
What does the systemic circuit do?
it carries blood to the body and back (drops off oxygen and picks up carbon dioxide)
what color is oxygenated blood?
red
what color is deoxygenated blood?
blue
what are the 4 chambers of the heart?
right and left atria
right and left ventricles
which two chambers contain oxygenated blood?
left atrium and left ventricle
which two chambers contain deoxygenated blood?
right atrium and right ventricle
what structure separates the two sides of the heart?
septum
what structures cover the atria?
auricles
what do the auricles do?
hold extra blood
what is the function of valves within the heart?
to stop blood flowing backwards
what are the 2 sets of valves?
atrioventricular valves (between atria and ventricles)
semilunar valves (between ventricles and major blood vessels.
what are the different atrioventricular valves?
tricuspid valves (between right atrium and right ventricle)
bicuspid valve (between left atrium and left ventricle)
what are the 2 different semilunar valves?
pulmonary valves (from pulmonary artery)
aortic valve (from the aorta)
what is the path of the deoxygenated blood in the body?
body tissues - vena cavae - right atrium - right ventricle - pulmonary artery - lungs
what is the path of the oxygenated blood in the body?
lungs - pulmonary veins - left atrium - left ventricle - aorta - body tissues
what is the intrinsic conduction system?
sets the basic rhythm of the beating heart by generating impulses which stimulate the heart to contract.
what is the path of the intrinsic conduction system?
SA node - AV node - AV bundle - bundle branches - Purkinje fibers
what is another name for the SA node?
the cardiac pacemaker
what is it called when the heart relaxes while beating?
diastole
what is it called when the heart contracts while beating?
systole
what happens during diastole?
atrial contraction (ventricles fill)
AV valves close causing lub sound
what happens during systole?
ventricles contract
semilunar valves close causing dub sound
isovolumetric relaxation
what is cardiac output?
how much blood is pumped out by each ventricle
how do you calculate cardiac output?
heart rate x stroke volume
what is stroke volume?
the volume of blood being pumped out by a ventricle in a heartbeat.
what is stroke volume affected by?
rapid blood loss and exercise
what is heart rate?
number of times your heart beats in a minute
what is heart rate affected by?
stress, hormones, ion concentration and physical factors
what are the three different types of blood vessels?
arteries, veins and capillaries
what do arteries do?
pump away from the heart
carry oxygenated blood (except pulmonary)
what do veins do?
carry blood to the heart
carry deoxygenated blood (except for pulmonary)w
what do capillaries do?
location of gas exchange
describe the flow of blood from artery to a vein.
artery - aterioles - capillaries - venuoles - vein
why is it helpful for capillaries to only have one cell layer?
gas exchange is more effective
what are the layers of the artery?
thick layer of muscle, lumen (where the blood flows)
what are the layers of the vein?
thin layer of muscle, lumen (where the blood flows)
which type of blood vessel receives high pressure blood?
arteries
which type of blood vessel receives low pressure blood?
veins
how do veins maintain blood pressure?
muscular pumping - muscles contract, squeeze blood through veins
one way valves
how can capillary sphincters restrict blood flow?
sphincters can close off different parts and slow down blood flow.
what are the functions of blood?
transport oxygen waste and hormones/nutrients
regualte body temperature, pH and fluid volume
prevent infections and blood loss
what is blood?
it is connective tissue made of cells suspended in a fluid matrix
what are the suspended cells known as?
formed elements
what is the fluid matrix known as?
plasma
what is hematocrit?
percentage of red blood cells in blood
what is the pH range of blood?
7.35 to 7.45
how many litres of blood do you have in your body?
5-6 litres
what is the composition of blood?
90% water and 10% dissolved gases, salts, minerals, nutrients, enzymes, hormones, waste and proteins
what are the three basic types of proteins found in plasma?
albumin - regulates osmosis between blood and tissues
globins - transports substances and fights infections
fibrinogens - used in blood clotting
what regulates the composition of plasma?
homeostasis
what are erythrocytes?
red blood cells
what is the function of erythrocyte?
transporting oxygen around the body via hemoglobin molecules
what is the structure of a erythrocyte and how does it help its function?
bioconcave shape allows for greater surface area
round sides make for efficient flow through blood vessels.
no nucleus & few organelles so they don't use up the oxygen while transporting it.
why must oxygen be carried by erythrocytes?
oxygen is non-polar so it can't diffuse into the blood.
what is hemoglobin?
a protein that is composed of 4 chains called globins
what does each globin contain?
a flat molecule called a hemew
what does a heme hold?
an iron atom, which can bind to one O2 molecule
how many O2 molecules can one hemoglobin hold?
four
what is a leukocyte?
white blood cell
what is the funciton of leukocytes?
to protect the body from pathogens
how is an erythrocyte different from a leukocyte?
very numerous
does not contain a nucleus
can live 100-120 days
confined to blood
consistent concentration
how is a leukocyte different from an erythrocyte?
less numerous
has a nucleus
can live for few days to years
can pass out of blood vessels (diapedesis)
concentration fluctuates
how are erythrocytes and leukocytes the same?
they are both formed elements
what is granulocyte?
they are a type of leukocyte that have low shaped nuclei and visible granuoles
what are some examples of granulocytes?
neutrophils, basophils, eosinophils
what are agranulocytes?
they are leukocytes that have spherical/kidney shaped nuclei and no visible granuoles
what are examples of agranulocyte?
lymphocyte and monocyte
neutrophils (function, shape, abundance)
they engulf and destroy bacteria
granuoles with lobe shaped nuclei
most common leukocyte and more are produced during infection
41-75% out of white blood cells
eosinophils (function, shape, abundance)
kill parasitic worms ingested in food
lessen allergic reactions
granuoles with two-lobed nuclei
1-5% out of white blood cells
basophils (function, shape, abundance)
release histamines which dialate blood vessels so that other leukocytes can rush in to fight infection or allergen -granuole
0-1% out of white blood cells
lymphocytes (location, shape, abundance, types)
usually found in lymphnodes instead of blood stream
two types T cells and B cells
agranuoles with large spherical nuclei
20-45% out of white blood cells
monocytes (function, shape, abundance)
leave blood, enter surrounding tissues, become macrophages
agranuoles with kidney shaped nuclei
3-8% out of white blood cells
what is the mneumonic device for leukocytes?
Never Let Monkeys Eat Bananas Neutrophils, Lymphocytes, Monocytes, Eosinophils, Basophils
what are thrombocytes?
they are platelets
what are thrombocytes made of?
tiny fragments of other cells
what is the function of thrombocytes?
responsible for blood clotting
what is the stimulating factor for producing blood cells?
hormones
what is hemostasis?
when a blood vessel is injured, platelets begin the process of forming a blood clot
what are the steps of hemostasis?
blood vessels contract to reduce blood loss
platelets chemically attract to the wound and stick together
injured tissue releases tissue factor (cause production of thrombin)
what does thrombin and fibronogen create?
fibrin mesh
what is a thrombus?
an abnormal clot that forms within a blood vessel
what is a thrombus called if it dislodges and floats through the blood?
embolus
how does an abnormal clot affect the body?
restricts the blood flow and can cause stroke, heart attack and death
what is an antigen?
a protein, peptide or polysaccharide that the body recognizes as friend or foe.
what does the immune system produce in the presence of an antigen?
antibodies
what does an antibody do to the antigens?
antibodies bind to the antigen and they clump together
what is it called when antibodies clump together?
agglutination
type A antigen and antibody
A antigens with anti-B antibody
type B antigen and antibody
B antigens with anti-A antibody
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