The circulatory system Flashcards
What are the main functions of the circulatory system?
1) it transports gases (from the respiratory system), nutrient molecules and waste materials (from the digestive system)
2) it regulates internal temperature and transports chemical substances (hormones) that are vital to health from one part of the body to the other
3) it protects against blood loss from injury and against disease-causing microbes or toxic substances introduced into the body
What are the the major components of the circulatory system?
1) heart: muscular organ that continuously pumps the blood through the body that generates blood flow
2) blood vessels: are a system of hollow tubes through which the blood moves
3) Blood: is the fluid that transports nutrients, oxygen, carbon dioxide, and many other materials throughout the body
What are the two types of circulatory systems?
1) Open circulatory system
2) closed circulatory system
What is an open circulatory system?
a circulatory system in which vessels open into the animal’s body cavity
~it is called “open” because blood flows freely within the body cavity and makes direct contact with organs and tissues (no distinction between the blood and the interstitial fluid)
Example: insects have this system
~in invertebrates (like insects) the mixture of blood and fluids that surrounds the cells is called hemolymph
What is a closed circulatory system?
a circulatory system in which the circulating blood is contained within vessels and kept separate from the interstitial fluid
~keeps the blood physically contained within vessels and separate from other body tissues
~blood follows a continuous fixed path of circulation and is confined to a network of vessels that keeps the blood separate from the interstitial fluid
Example: vertebrates, earthworms, squid and octopus’ have this system
explain: blood vessels
Vein: ~65% of blood in in here ~valve is one-direction only ~thin walled ~most have oxygenated blood except for the pulmonary vein, it carries oxygenated blood ~low pressure Artery: ~30% of blood is here ~away from heart ~thick, muscular walls ~most have oxygenated blood ~except for pulmonary artery (carries deoxygenated blood to the lungs to get rid of it) ~high pressure Capillary: ~5% of blood is here ~between vein and artery -->junction ~very thin walls (transparent) ~diffusion
What is a pulmonary loop?
Carries blood to the lungs
What is a systemic loop?
Carries blood to the body
Explain:red blood cells and their functions
~athletes do high-altitude training because people at higher altitudes have more red blood cells than people living at ocean level because there is less oxygen in the higher altitudes so they need more blood cells to store the oxygen
~this would give athletes more energy to burn while racing
~illegal in sports–>called “blood doping”
Explain Temperature Regulation
~when your body is very hot, it sends the blood to the extremities and the surface of your skin to try to get rid of the heat
~when you’re very cold (i.e buried in snow) your body takes the blood from the extremities and sends it to your core (all necessary places to keep you alive)
~if you’re in the cold and you are found and they give you a shot of alcohol but remain in the cold, since all your blood is at the surface you will lose all the heat quickly and die
Explain: blood pressure
120 systolic the highest pressure
——- = ————- = —————————-
80 diastolic the lowest pressure
What is systolic pressure?
the pressure generated in the circulatory system when the ventricles contract and push blood from the heart
What is diastolic pressure?
the pressure generated in the circulatory system when the ventricles fill with blood
What is hypertension (high blood pressure)?
continuous high blood pressure
(i.e.145+ )
——-
90
What are the circulatory system disorders?
1) arteriosclerosis
2) Aneurysm
3) Congenital Heart Defect
4) Leukemia
