Cardiovascular
system
, Types of circulatory systems:
● Open circulatory system:
• Blood vessels lead to a cavity in the body. Inside the body the blood moves freely in all directions.
• Blood flow is slow and restricted e.g. In crabs, spiders and insects.
● Closed circulatory system:
• Blood flows from one type of blood vessel to another.
• The blood constantly flows in one direction and never leaves the blood vessels.
• Blood flow is fast and efficient e.g. In vertebrates.
● There are two types of transport systems in humans:
• A closed circulatory system
• An open lymph system
, The circulatory system in humans:
• Some animals have a single circulatory
pathway, which means blood only flows through
the heart once per circulation e.g. Fish.
• Humans have a double circulatory pathway,
which means blood flows through the heart
twice per circulation. The first time the blood is
pumped from the heart to the lungs (pulmonary
circulation) and the second time it goes to the
rest of the body (systemic circulation).
Systemic circulation:
• Circulation of blood between the heart and the
rest of the body. Oxygenated blood comes back
to the heart.
• Oxygenated blood: contains oxygen and is
bright red in colour.
• Deoxygenated blood: contains no oxygen and
is blueish-red in colour
system
, Types of circulatory systems:
● Open circulatory system:
• Blood vessels lead to a cavity in the body. Inside the body the blood moves freely in all directions.
• Blood flow is slow and restricted e.g. In crabs, spiders and insects.
● Closed circulatory system:
• Blood flows from one type of blood vessel to another.
• The blood constantly flows in one direction and never leaves the blood vessels.
• Blood flow is fast and efficient e.g. In vertebrates.
● There are two types of transport systems in humans:
• A closed circulatory system
• An open lymph system
, The circulatory system in humans:
• Some animals have a single circulatory
pathway, which means blood only flows through
the heart once per circulation e.g. Fish.
• Humans have a double circulatory pathway,
which means blood flows through the heart
twice per circulation. The first time the blood is
pumped from the heart to the lungs (pulmonary
circulation) and the second time it goes to the
rest of the body (systemic circulation).
Systemic circulation:
• Circulation of blood between the heart and the
rest of the body. Oxygenated blood comes back
to the heart.
• Oxygenated blood: contains oxygen and is
bright red in colour.
• Deoxygenated blood: contains no oxygen and
is blueish-red in colour
