Circulatory systems Flashcards
Main components of blood circulatory systems
- Heart
- Blood vessels
- blood
Open circulatory systems
- Blood flows freely over tissues,
- Through an open cavity called a haemocoel
- Blood flows slowly at low pressure
- No control over the blood’s distribution
- Found in some small animals like arthropods
Closed circulatory systems
- Blood flows all the time in a system of vessels – arteries, veins and capillaries
- Leaves heart and arteries branch to eventually form capillaries
- Capillaries join up again to form veins that takes blood back to the heart.
- Found in all vertebrates including humans and all mammals
Double pump closed circulation
- The heart has four chambers
- That function as two separate pumps
- Systemic and pulmonary circulation
- Found in all mammals
Size and shape of the human heart
- About the size of your fist
- Hollow, pear shaped muscular organ
- Upper end wider than lower end that points down and to the left
Where the heart is located
- Found in the thoracic cavity
- Above your diaphragm between the lungs
- Protected by the sternum and ribs
- Large blood vessels enter and leave it at the top and keep it in position.
Pericardium
- A double walled membrane
- Enclosing the heart
How the heart is protected from friction
- Watery fluid
- Between the pericardium
- Prevents friction between heart and surrounding organs
How the heart itself gets blood
- Coronary blood vessels
- coronary arteries
- coronary veins
Muscular wall dividing heart into left and right side
Septum
Side of the heart with oxygenated blood
Left
Side of the heart with deoxygenated blood
Right
The four chambers of the heart
- Left atrium
- left ventricle
- Right atrium
- right ventricle
Describe the upper chambers of the heart
- Atria
- Receiving chambers
- Thinner muscular walls
Describe the lower chambers of the heart
- Ventricles
- Pumping chambers
- Thicker muscular walls
Endocardium
- Inside lining of the heart
- Thin membrane of squamous epithelium
Describe where the right hand side of the heart would be as you look at a picture of it
On the left of the picture.
Veins that open into the right atrium
- Superior vena cava
- Inferior vena cava
Valve separating the right atrium from the right ventricle
- tricuspid valve
- Three valve flaps
bicuspid valve
Valve separating the left atrium from the left ventricle
Blood in the superior vena cava
- Deoxygenated
- From the head and arms to the right atrium
Blood in the inferior vena cava
- Deoxygenated
- From the lower limbs and abdomen
Blood in the pulmonary arteries
- Deoxygenated
- From the right ventricle to the lungs
Valve between the right ventricles and the pulmonary artery
Semilunar pulmonary valve