Transport in Animals Flashcards
Describe the vascular system of insects.
- Open circulatory system.
- Dorsal-tube shaped heart
- Respiratory gases not carried in blood.
Open circulatory system
The transport medium pumped by the heart is not contained within vessels, but moves freely. Transport fluid comes into direct contact with the cells.
Describe the vascular system of earthworms.
- Vascularisation.
- Closed circulatory system.
- Respiratory gases carried in blood.
Close circulatory system
The blood is pumped by the heart is contained within the blood vessels. Blood does not come into direct contact with the cells.
Advantages of a closed circulatory system.
- Blood pressure can be maintained.
- Blood supply to different organs can vary.
- Lower volumes of transport fluid required.
Single circulatory system
A circulatory system in which the blood travels one circuit. Blood flows through the heart and is pumped around the body before returning to the heart.
Double circulatory system
A circulatory system in which the blood flows through the heart twice in two circuits. Blood is pumped from the heart to the lungs before returning to the heart. It is then pumped around the body, after which it returns to the heart again.
Advantages of a double circulatory system.
- Maintains blood pressure around the whole body.
- Uptake of oxygen is more efficient.
- Delivery of oxygen and nutrients is more efficient.
- Blood pressure can differ in pulmonary and systemic circuits.
What are the names of the two circuits that blood enters the heart through?
Pulmonary circuit and systemic circuit.
Name the four chambers of the mammalian heart.
- Left atrium
- Right atrium
- Left ventricle
- Right ventricle
Outline the pathway of blood around the body.
Pulmonary vein, Left atrium, Left ventricle,
Aorta, Body, Vena Cava, Right atrium, Right ventricle, Pulmonary artery, Lungs.
Atrioventricular valves (AV)
Are found between the atria and ventricles and they prevent the back flow of blood from the ventricles into the atria.
There are two types; Bicuspid (left side) and Tricuspid (right side).
Semi-lunar valves
Are found between the ventricles and arteries and they prevent the backflow of blood into ventricles.
List the 5 types of blood vessels.
Arteries, arterioles, capillaries, venules and veins.
Outline the pathways of blood through the blood vessels.
Heart, arteries, arterioles, capillaries, venules, veins and heart.
Function of arteries
Carry blood away from the heart to the tissues, under high pressure.
Relate the structure of arteries in relation to their function
- Thick, muscular walls to handle high pressure without tearing.
- Elastic tissue allows recoil to prevent pressure surges.
- Narrow lumen to maintain pressure.
Function of veins
Carry blood towards the heart under low pressure.
Relate the structure of veins related to their function
- Thin walls due to lower pressure.
- Require valves to ensure blood doesn’t flow backwards.
- Have less muscular and elastic tissue as they dont have to control the blood flow.