Blood and the circulatory system Flashcards
What are the four components of blood
Blood is made up of four parts or components: plasma, red blood cells, white blood cells and platelets
What is plasma
Plasma is the liquid part of blood. It is a pale yellow colour and is mostly made of water.
What is the purpose of plasma
it transports chemicals and heat around the body.
What do white blood cells do
White blood cells fight infection
Name the different type of blood vessels
There are three main types of blood vessels: arteries, veins and capillaries.
What are veins and what do they do
Veins carry blood to the heart. The blood flow or pressure in a vein is low. The low pressure means that veins can have thinner, weaker walls than arteries. To prevent blood flowing backwards in veins they have valves at regular intervals.
What is the function of capillaries
Capillaries allow materials to pass in and out of the bloodstream.
What do valves do
Valves in the heart make sure that blood can only flow in one direction.
On average how much does an adult heart beat per minute
On average the adult heart beats 70 times a minute
What effect does exercise have on the heart and body
Exercise causes us to breathe faster.
Exercise causes the heart to contract more strongly.
Exercise increases the strength of the muscles in our arms and legs and it also increases the strength of our heart.
Exercise helps to reduce weight.
Why does heart disease mainly occur
arteries that supply blood to the heart becoming clogged with fat.
