Biology - The Circulatory System Chapter 9 Unit B2

what does the circulatory system compose of

the blood, the blood vessels and the heart

what is the function of the circulatory system

transport blood components and other substances in the blood, and to protect against disease

function of red blood cells

to carry oxygen around the body

function of white blood cells

to defend against diseases

function of platelets

convert the protein fibrinogen to fibrin which forms a mesh network that traps other blood components to form scabs.

function of plasma

the liquid part of the blood responsible for the transport of the blood cells, absorbed food molecules, carbon dioxide, hormones and urea

how are red blood cells adapted for their function

biconcave shape: large surface area for diffusion

haemoglobin: rich in iron that carries the oxygen

no nucleus: more space for haemoglobin

what do lymphocytes do

produce antibodies

what do phagocytes do

engulf and digest microorganisms in a process called phagocytosis

what are the three types of blood vessel

arteries, veins and capillaries

features of arteries

thick wall of muscle and elastic fibres, small lumen, high blood pressure

features of veins

relatively thin wall of muscle and elastic fibres, large lumen, valves, low blood pressure

features of capillaries

very thing lining (one cell thick), low blood pressure

what type of blood does the pulmonary vein carry

oxygenated

what type of blood does the aorta carry

oxygenated

what type of blood does the vena cava carry

deoxygenated

what does the pulmonary artery carry

deoxygenated

what does the hepatic artery carry

oxygen and glucose

what does the hepatic portal vein carry

digested food

what does the hepatic vein carry

glucose, amino acids, carbon dioxide

what type of blood does the renal artery carry

oxygenated blood rich in urea

what type of blood does the renal vein carry

deoxygenated blood that is purified, and carbon dioxide

what is double circulation

the idea that the blood travels through the heart twice in one complete circulation of the body.

what does LORD stand for

Left side receives Oxygenated blood and delivers it to the body tissues, Right side receives Deoxygenated blood and delivers it to the body tissues

what are the benefits of exercise for the heart

strengthens the heart muscle, increases the heart rate, and increased blood pressure

what is the benefit of a stronger heart

will have an increased cardiac output

define cardiac output

the volume of blood pumped by the heart, per minute.

define pulse rate

how often a heart beats

define recovery rate

the time it takes for the heart to return to normal rate after exercise

define resting rate

the heart rate at rest; lower for fitter people

how does exercise influence respiration

it causes the heart rate to increase, so our muscles get more oxygen and glucose to produce energy for respiration.

why are ventricle walls thicker than atria

they work harder and pump more to get blood to all the organs and against gravity to get back up to the head

why is the left ventricle wall thicker

as it must pump blood around the whole body, not just to the lungs