Bio Ch 32 Flashcards
Circulatory system
moves fluid between various parts of the body
Blood
1 type of circulatory fluid, which is always contained within blood vessels
Hemolymph
type of circulatory fluid, a mixture of blood and tissue fluid, which fills the body cavity and surround the inner organs
Open circulatory system
hemolymph is seen in animals with this, which consists of blood vessels plus open spaces
Closed circulatory system
blood is seen in animals with this, in which blood does not leave the vessels
Cardiovascular system
all vertebrate animals have a closed one of these consisting of a strong, muscular heart in which the atria (sing., atrium) receive blood and the muscular ventricles pump blood through the blood vessels
Arteries
carry blood away from the heart
Capillaries
exchange materials with tissue fluid
Veins
return blood to the heart
Arterioles
small arteries whose diameter can be regulated by the nervous and endocrine systems; constriction and dilation of these affect blood pressure; greater the number of these dilated
Venules
along with veins, collect blood from the capillary beds and take it to the heart; drain blood from capillaries
Systemic circuit
heart pumps blood to the tissues through this
Pulmonary circuit
heart pumps blood to the lungs through this
Heart
cone-shaped, muscular organ about the size of a fist; located between the lungs directly behind the sternum (breastbone) and is tilted so the apex (pointed end) is oriented to the left
Septum
this wall separates the heart into a right side and a left side
Atrium (pl., atria)
two, upper, thin-walled chambers with wrinkled, protruding appendages called auricles
Ventricles
two lower thick-walled chambers, which pump blood away from the heart
Atrioventricular valves
two valves that lie between the atria and the ventricles that are supported by strong fibrous strings called chordae tendineae
Semilunar valves
valves between the ventricles and their attached vessels whose flaps resemble half-moons; pulmonary and aortic types
Systole
refers to the contraction of the heart chambers
Diastole
refers to relaxation of these chambers
Cardiac cycle
one complete cycle of systole and diastole for all heart chambers