2.3 Open or closed circulation Flashcards
(27 cards)
What are the features of a transport system?
- A suitable medium to carry materials.
- A pump for moving blood.
- Valves to maintain the flow in one direction.
What do some transport systems have?
- Respiratory pigment
- A system of vessels with branching network to distribute the transport medium to all parts of the body.
What organisms have an open circulatory system?
Insects.
What does the blood do in an open circulatory system?
The ‘blood’ bathes all the cells and organs of the body.
What is the blood in an open circulatory system called?
The haemolymph.
Where is the haemolymph?
In the body cavity or haemocoel.
Does the haemolymph have red blood cells?
No.
How is oxygen delivered to tissues in a closed circulation?
Delivered directly to the tissues by the tracheae.
Do animals with an open circulatory system have a heart?
Many of them do.
What does blood travel through in a closed circulatory system?
Through blood vessels.
What is the impetus generated by in a closed circulatory system?
A muscular pump or heart.
Closed circulatory systems deliver blood quickly to tissues under what?
Pressure.
What do red blood cells contain in a closed system?
Haemoglobin.
What organisms has a closed single circulatory system?
Earthworms or fish.
How does the blood move in an earthworm?
Forward in the dorsal vessel, and back in the ventral vessel.
In an earthworm, what pumps the blood?
5 pair of ‘pseudohearts’, that are actually thickened, muscular blood vessels.
What is a single circulation?
Blood passes through the heart once in each circulation.
What is the disadvantage of single circulation?
Blood loses pressure around the circuit, resulting in slower circulation.
What is double circulation?
The blood passes through the heart twice in one circulation of the system.
What is the advantage of double circulation?
Blood is repressurized when it leaves the gas exchange surface, giving a faster and more efficient circulation to the tissues.
Where does deoxygenated blood return from? (dc)
The head and body.
Where does deoxygenated blood go? (dc)
To the right-hand side of the heart.
Where does the blood pass through after the right-hand side of heart? (dc)
The lungs on each side.
Where does blood go after passing through the lungs? (dc)
The left side of the heart.
