The Heart
Left Atrium
Right Ventricle
Right Atrium
Left Ventricle
Septum
Atrio-Ventricular Valve
Tendons
Pocket Valve
Helpful Hints
Homer’s Right Hand
Homer’s Left Hand
Right Side of Homer’s Heart
Left Side of Homer’s Heart
Diagrams of the heart usually show the heart as if you were looking at it in someone else’s chest
The plural of atrium is… atria …because atrium is a Latin word!
…oxygenated blood.
…deoxygenated blood.
… muscle
Vena Cava……from body
Pulmonary Artery…
…to lungs
Pulmonary Vein…
…from lungs
Aorta……to body
Walls of the heart are made of …
The walls of the left ventricle are much thicker than the walls of the right ventricle because ……the left ventricle has to pump blood much further.
The right side of the heart carries…
The left side of the heart carries…
Filling the Heart
…the body
(Vena Cava)
Right atrium fills with blood from…
Left atrium fills with blood from…
… the lungs
(Pulmonary Vein)
Atrio-Ventricular valves are…OPEN
Blood flows from the atria into the ventricles
Pocket valves are…CLOSED
Blood cannot flow back from the Pulmonary Artery and Aorta into the Ventricles
Heart muscle is…RELAXED
Blood flows from the Ventricles into the Pulmonary Artery and Aorta
Blood from the Ventricles cannot flow back into the Atria
Emptying the Heart
Heart muscle is…CONTRACTING
Atrio-Ventricular valves are…CLOSED
Pocket valves are…OPEN
To Lungs(Pulmonary Artery)
To Body & Head(Aorta)
carbon dioxide…
Oxygenated Blood
Deoxygenated Blood
Lungs
Heart
Head
Body
Pulmonary Circulation
Systemic Circulation
…and gains…carbon dioxide… oxygen
…and gains…
oxygen
In the lungs, blood loses…
In the tissues of the body, blood loses…
… arteries
Blood is carried away from heart by…
… capillaries
Arteries divide to form…
… veins
Capillaries join to form…
Veins carry blood back to the heart
Blood Pressure DECREASES as it flows
round system
Arteries are adapted to deal with blood under HIGH
pressure
Thick outer wall
Thick layer of muscle and elastic fibres
Narrow lumen(space through which blood flows)
Veins are adapted to deal with blood under LOW
pressure
Wide lumen
Thinner outer wall than arteries
Thinner layer of muscle and elastic fibres than arteries
Veins also have valves to……keep blood flowing in the right direction
…TOWARDS heart …AWAY
FROM heart
Valves open to allow blood to flow…
Valves close to stop blood flowing…
Carbon dioxide and other wastes diffuse from the cells to the
blood
Oxygen, food molecules and
hormones diffuse from the blood to the
cells
Capillaries are adapted for ……exchange of materials.
…only one cell thick
…allow plasma to leak in and out
(They are just large enough for a red blood cell to squeeze through)
This means that blood in the capillaries moves very…SLOWLY
Gaps between cells in capillary wall…
Wall of capillary is very thin…
The capillaries are very narrow.
Cells in Body Tissues
The Blood is made up of four components…
Red Blood Cells
Carry oxygen
White Blood Cells
Fight infections
Cell fragments called…
…platelets
Help with blood clotting
A straw-coloured
liquid called…
…plasma
Carries dissolved
substances:
Carbon dioxideOther wastesFood
moleculesHormones
Red Blood Cells are adapted for carrying oxygen
Shape:Biconcave disc
… surface area for absorption of oxygen
Dimple on either side of cell increases…
…haemoglobinCell is packed with … nucleus
This make s more room for… haemoglobin.
Mature red blood cell has no…
Haemoglobin +Oxygen OxyhaemoglobinIn the Lungs
In the BodyTissues