Circulation and The Heart Flashcards
Function of a Circulatory System
transports many essential materials around the body including…
- Oxygen from the respiratory system
- Nutrients from the digestive system
- Hormones from the endocrine system
- Chemicals and cells (white blood cells/antibodies) from the immune system
- Metabolic wastes from the cells to the lungs and kidneys
- Thermal energy
Why Do We Need Circulation?
- circulation became needed after eveloping species had more cells, and less were touching outside air
- allows for oxygen and nutrients to be delivered to every cell in the body
- allowed for wastes in the these cells to be removed from the body
Kep features of cirlatory system
- A fluid that transports or circulates materials throughout the body
- A network of tubes in which the fluid circulates
- A pump that pushes the fluid through the tubes
no circulatory system
- Not all living things have a circulatory system
- unicellaur organism (fungi, bacteria and archea) exchange gases direly with enviomrnets; do not need cirlatory system
- simple multicelluar organisms use internal body cavity lining covered in flagella to move fluid in body
Open cirucltory system
- circulating fluid is pumped into a connected system of body cavities ( sinuses)
- these openings bathe the cells in hemolymph (fluid and blood)
- may have 1 or more hearts to move blood
- in invertibraies
Cons of open cirulatory system
- inefficient method of circulation because the hemolymph is under low pressure and circulates slowly
- practical for many animals with low metabolic rates which therefore have lower oxygen and energy demands
closed cirualory system
- the fluid(blood) is contained within a network of tubes called blood vessels
- The blood and tissue fluid are always separate
- there is a lot of variation in the structure of closed circulatory systems
The Human Heart
- muscular organ found in the middle of your chest directly under your breastbone,
- the center of your circulatory system
- two atria, which receive blood from your body at the top of the heart
- two ventricles, which receive blood from your atria at the bottom of the heart
The Human Heart walls
- ventricular walls are much thicker and more muscular than the atria
- This is because the ventricles have to pump blood a much longer distance
- the atria do not have to pump blood far there is less muscle required
The Human Heart two sides
- divided into two sides by the septum
- The right side of your heart receives blood from your systemic (body) circuit and circulates blood to your pulmonary (lung) circuit
- The left side of your heart receives blood from your pulmonary (lung) circuit and circulates blood to your systemic (body) circuit
Vena Cava
- Blood enters your right atrium from one of two blood vessels
- Blood from your upper body tissues from your superior vena cava
- Blood from your lower body tissues enters from your inferior vena cava
Circulation Through the Heart right side
-deoxygenatedblood enters right atrium and enters right ventricle through tricuspid value
- valve is supported by tough cords called chordae tendineae and prevent blood from flowing backwards
- Blood then leaves your right ventricle through the pulomanry valves to go towards your lungs via your left pulmonary arteries
Circulation Through the Heart left side
- Blood is then oxygenated in the lungs and returns to your heart via the pulmonary veins
- It enters your left atrium, and then is pushed towards your left ventricle through the mitral valve
- Blood then get pushed through the arotic valve and enters the aorta so it can be distributed though the body
The Human Heart demands
- heart has a high demand for oxygen because it is constantly working
- the heart has its own supply of blood vessels called the coronary blood vessels
- branch off the aorta
Versions of closed cirulatory system
Arotic Arch: found in worms
Two chamered heart: In fish
3 chambered heart: foun din alphibiams (frogs)
4 chambered heart: found in reptiles, mammals, birds
