circulatory system Flashcards
what does the circulatory system do?
- transport oxygen, nutrients, and other substances
- removes waste material from tissues
2 types of circulatory systems
1) open
2) closed
features of open circulatory system
- no true heart or capillaries
- blood vessels pump blood into body cavity
- blood vessels join directly with open sinuses
- blood flow is slow
- no transport of gas
features of a closed respiratory system
- capillary system is present
- blood pumped through vessels by heart
- includes arteries and veins
- blood flow is rapid
- gas is transported
- contains 2 parts: pulmonary and systemic circulation
advantages of an open circulatory system
- less energy for distribution
- gives animals greater control over body temo
disadvantages of an open circulatory system
- low metabolism rate
- not a lot of variability to oxygen uptake (changes are low)
advantages of a closed circulatory system
- more efficient
- increases capacity to distribute oxygen to muscle tissues
- efficient distribution of antibodies
disadvantages of a closed circulatory system
- more energy
- more complex
- bigger animals
where is the heart located
in the thoracic cavity in mediastinum
size of the heart
a closed fist
speed of heart pump
- 72 beats/minutes
- 70 ml/beat
what are the walls of heart made of
cardiac muscle
how many chambers does the heart of a mammal have
4 chambers: 2 atria and 2 ventricles
how many valves do the heart have
4 valves:
- atrioventricular: triscupid and bicuspid
- semilunar: aortic and pulmonary
importance of valves in the heart
prevent blood from flowing back
tricuspid valve
prevents blood from flowing back to the right atrium when right ventricle contracts
bicuspid valve
prevent blood from flowing back to the left atrium when left ventricle contracts
aortic valve
prevents blood flowing to left ventricle
pulmonary valve
prevents blood from flowing back to right ventricle
types of circulation
1) pulmonary
2) systemic
pulmonary circulation
right side pumps oxygen-poor blood from heart to lungs
sytemic circulation
pumps oxygen rich blood to the rest of the body
how many sounds are there in 1 cardiac cycle
1) lubb
2) dubb
lubb sound
ventricles connect, tricuspid and bicuspid valves snap shut