Heart and blood vessels

Blood components, vessels and other stuff

What are the four main blood components?

White blood cells, Red blood cells, Platelets and Plasma

What is Plasma?

55% of the blood.

Carries hormones, amino acids, water, proteins.

Carries carbon dioxide and urea for waste disposal.

What are the adaptations of a RBC?

44% of the blood.

Has haemoglobin so that the oxygen can bind to it (makes the RBC bright red).

Has no nucleus for more space for the haemoglobin and oxygen

Biconcave shape to maneuver through blood vessels and maximises surface area.

What is a WBC?

Less than 1% of the blood.

Fights pathogens, produces antibodies and anti toxins to neutralize toxins.

Engulfs pathogens.

What is the function of platelets?

They form a fibre mesh at the wound site to clot blood and stop any infections from entering or blood loss.

What is an ARTERY?

Carries OXYGENATED blood AWAY from the heart.

Thick layer of muscle and elastic tissue to ensure arteries don’t rupture and small lumen.

High pressure blood flow.

What is a VEIN?

Carries DEOXYGENATED blood TOWARDS the heart.

Thin wall due to slow pressure.

Large lumen

What is the purpose of a VALVE

To prevent backflow of blood.

Muscles relax - valves close.

Muscles contract - valves open.

What is a CAPILLARY and its adaptations?

Tiny vessles that link arteries to veins.

1 cell thick to allow diffusion of glucose and oxygen into cells.

What are CORONARY ARTERIES?

A blood supply to the heart.

What is a stent?

A metal alloy placed into the coronary arteries to prevent them from closing.

What are statins?

Drugs that help lower cholesterol by lowering production in liver but have some side effects:

Once taken you can’t stop otherwise high cholesterol will return.

Memory loss, type 2 diabetes, and liver failure .

What are pacemakers?

Located in the right atrium wall.

Group of cells that control the rhythm of the heart.

Artificial pacemakers are an electrical device that sends strong electrical impulses to mimic the natural pacemakers and keep a healthy rhythm.

What is the order of the double circuit?

Pulmonary veins - left atrium - left ventricle- aortic valves - capillaries -

vena cava - right atrium - right ventricle - pulmonary valve - pulmonary artery - lungs -

Example and disadvantages of single circulatory system

Fish- heart to gills to organs and back to heart.

Less pressure so blood reaches organs slowly and less oxygen delivered

Coronary heart disease

Buildup of fatty materials inside coronary arteries - causing them to narrow and not enough oxygen reaches the heart.

Cardiovascular disease

The heart cannot pump enough blood around the body

Solved by transplant

Alveoli adaptations

Huge surface area due to folds and millions

Very thin walls- short diffusion pathway

Very good blood supply- maintains conc gradient

Benign cells

The growth of abnormal cells in one area usually contained in a membrane

They do not invade other parts of the body

Malignant cells

Invade neighbouring tissues and move into bloodstream.