fluid, channels, and pump
What is the three major parts to the circulatory system?
blood
fluid that serves as a medium of transport
blood vessels
a system of channels that conduct the blood throughout the body
heart
a pump that keeps the blood circulating
open circulatory system
space within the body cavity; hemocoel. found in arthropods and most mollusks
closed circulatory system
confined blood in continuous vascular network with a pumping heart. found in some invertebrates and all vertebrates
1. transport Oxygen and carbon dioxide. 2. distribution of nutrients. 3. transport of waste. 4. distribution of hormones. 5. regulation of body temperature. 6. protection of body against blood loss and disease
What are the functions of the vertebrate circulatory system?
atria
collect blood from body. Contract and deposit blood in ventricles
ventricles
contract and discharge blood to body
2 chambered hearts
earliest vertebrate hearts with one atrium and one ventricle
fish
Example of an animal with a 2 chambered heart?
3 chambered hearts
have 2 atria and one ventricle
amphibian and most reptiles
Example of an animal with a 3 chambered heart?
4 chambered heart
most advanced heart, have 2 atria and 2 ventricle.
bird and mammal hearts
Example of animals with a 4 chambered heart?
veins and arteries
What are the two types of blood vessels connect to heart chambers?
veins
carry blood to atria
arteries
carry blood away from ventricles
1. Atria contract, forcing blood into ventricles. 2. then the ventricles contract, forcing blood through arteries to the lungs and the rest of the body. 3. the cycle ends as the heart relaxes
Explain the three steps to the Cardiac cycle
blood pressure
Heart chamber contraction generates what?
systolic pressure
blood pressure during ventricular contraction
diastolic pressure
blood pressure during ventricular relaxation
heart valves
insure one-way flow of blood through heart
artioventricular valves
allows blood to flow from atria to ventricles
semilunar valves
is a valve between the right ventricle and the pulmonary artery that allows blood to flow
pacemaker cells
coordinate cardiac cycle
sinoatrial (SA) node
primary pacemaker in upper wall of right atrium. generates impulses that spread throughout cardiac muscle cells of atria
atrioventricular (AV) node
stimulated by SA node impulse. sends impulse to ventricles by excitable fibers.
electrocardiogram (ECG)
used to monitor both normal (top) and abnormal electrical activity (bottom) heart activity
at rest, parasympathetic nervous system slows heart rate. during exercise and stress, sympathetic nervous system increases heart rate
nervous system control of heart rate?
under stress the hormone epinephrine is released. this stimulates SA node and increases heart rate
endocrine system control of heart rate?
plasma
fluid portion of the blood
cellular components
made of red blood cells, white blood cells, and platelets
hormones, nutrients, gases, salts, wastes, proteins
other components of plasma
albumins, globulins, fibrinogen
Three major types of plasma proteins
albumins
maintain osmotic pressure of blood
globulins
transport nutrients and act in immunity
fibrinogen
involved with blood clotting
red blood cells
carry oxygen from lungs to tissues; also called erythrocytes
hemoglobin
what causes the red color in red blood cells
hemoglobin
composed of 4 polypeptide chains and 4 iron-containing heme groups
erythropoitin
released by kidneys as a hormone when oxygen levels are low. this stimulates additional red blood cell formation by bone marrow
negative feedback
red blood cell formation is controlled by what?
white blood cells
also called leukocytes; most protected body against disease
lymphocytes and macrophages
examples of white blood cells?
lymphocytes
can produce antibodies used in immunity
macrophages
mobile and amoeba-like; arms that can reach out. engulf foreign particles and bacteria
platelets
made of pieces of magakaryocytes from red bone marrow. involved in clotting
blood clot
formed from sticky fibrin protein threads, platelets, forming patch over wound site
thrombin and fibrinogen
contribute to clot formation
arteries, arterioles, capillaries, venules, veins, back to heart
blood flow through blood vessels
arteries
thick walled vessels; contains smooth muscle and elastic tissue to withstand high pressure
elastic recoil
maintains blood pressure during diastole
capillaries
tiniest vessels. allows exchanged of materials between blood and body cells
venules
capillaries merge to later form this?
veins
wider, thinner walled and more expandable than arteries. contain on-way valves that allow blood to flow only to heart in one direction
precapillary sphincter muscles
capillary blood flow is controlled by this?
1. return excess interstitial fluid to blood stream. 2. transport fats from small intestine to blood stream. 3. contribute to immunity
Functions of lymphatic system?
lymphatic capillaries
collect excess interstitial fluid from tissues; "dead-end" in body tissues
tonsils
patches of connective tissue containing many lymphocytes; destroy bacteria and viruses
lumph nodes
kidney-shaped structures found connecting lymph vessels; destroy foreign particles in lymph
thymus
found above heart; important site of lymphocyte development
spleen
found in abdominal cavity; similar to lymph node, but filters blood. destroys old red blood cells
reptiles
In which vertebrate does on see a partial partition in the ventricle?
HDL
What is the "good" cholesterol?
it can move blood more efficiently
What is the advantage of a closed circulatory system over an open one?
it must pass the blood through the systemic circulation
the left ventricle is more muscular than the right ventricle because?
left ventricle
Which heart chamber supplies oxygenated blood to the heart muscle?
the right atrium and right ventricle
Which set of chambers supplies blood to the pulmonary circulation?
left ventricle
Which heart chamber is the most muscular?
gap junctions
allow rapid passage of electrical signals among heart cells
capillaries
Ventricles force blood directly into what?
cardiac cycle
the alternating relaxation and contraction of heart chambers
erythropoietin
is produced by kidneys
keep the blood from flowing backward when the veins are squeezed by the skeletal muscles
the role of valves in the veins is to?
lymph
when interstitial fluid enter the lymphatic system it is known as ?
the spleen and the thymus
what two organs are considered to be part of the lymphatic system
interstitial fluid
plasma that leaks from the capillaries into the tissue spaces is known as