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