Flashcards in 3.2- Transport in animals Deck (58)
What is the difference between a single and double circulatory system?
In a single circulatory system, blood only passes through the heart once for each complete circuit of the body
In a double circulatory system, the blood passes through the heart twice for each complete circuit of the body
Which organisms has a single circulatory system?
Which organisms has a double circulatory system?
What is the pulmonary system?
The side of the circulatory system that sends blood to the lungs from the heart
What is the systemic system?
The side of the circulatory system that sends blood from the heart to the rest of the body
What is an advantage of the mammalian doubles system?
It gives the blood an extra push so blocking travel faster and oxygen can be delivered more quickly
What type of circulatory system do all vertebrates have?
Closed - blood is enclosed inside blood vessels
What type of circulatory system do insects and some invertebrates have?
Open - blood isn't enclosed in blood vessels and flows freely through the body cavity
How does blood flow around the body in an open circulatory system?
The heart is segmented and contracts like a wave
This pumps the blood into a single main artery
This artery opens up into the body cavity
The blood flows around the insect organs before going through valves back to the heart
What is the system that supplies insects with oxygen?
Tracheal system- not the circulatory system
What is the role of the circulatory system in insects?
Supplies the insects cells with nutrients and transport things like hormones around the insect
What are the 5 types of blood vessels called?
How are arteries adapted for their functions?
They have thick and muscular walls and elastic tissue which maintains a high pressure
The endothelium is folded which allows the artery to expand under high pressure
How are arterioles adapted for their functions?
Arterioles have a layer of Smooth muscle but less elastic tissue.
The smooth muscle allows and to expand or contract and control the amount of blood flowing to tissues
How are capillaries adapted for their functions?
Capillary walls have an endothelium which is only one cell thick.
This allows efficient diffusion to a car
How are venules adapted for their functions?
Venues have very thin walls that contain some muscle cell
This allows them to form veins
How are veins adapted for their functions?
Veins have a large lumen and very little elastic or muscle tissue
They contain valves to stop blood flowing backwards
This helps them take blood back to the heart under low pressure
What is tissue fluid?
The fluid that surrounds cells in tissues
It is made from substances that leave the blood plasma but doesn't contain red blood cells or big proteins
How is tissue fluid formed?
At the start of the capillary bed, the hydrostatic pressure in the capillaries is greater than the hydrostatic pressure in the tissue fluid which forces fluid out of the capillaries and into the spaces around cells
What happens after tissue fluid is formed around the cells?
The hydrostatic pressure reduces in the capillaries so it is much lower at the end of the capillary bed
This means oncotic pressure is high at the venule end so some watery enter from the tissue fluid by osmosis
What happens to excess tissue fluid that doesn't re-enter the capillaries?
It is returned to the blood through the lymphatic system
How is lymph returned to the blood?
valves in the lymph vessels stop the lymph going backwards
Lymph moves towards the main lymph vessel in the thorax where it's returned to the blood near the heart
Are red blood cells found in blood, tissue fluid and lymph?
Tissue fluid: No
They are too big to get through the capillary walls
Are white blood cells found in blood, tissue fluid and lymph?
Tissue fluid: Very few - only enter tissue fluid when there's an infection
Lymph: Yes- most of found here
Are platelets found in blood, tissue fluid and lymph?
Tissue fluid: No- only if the capillaries are damaged
Are proteins found in blood, tissue fluid and lymph?
Tissue fluid: Very few- most of too big to get through
Lymph: Only antibodies
Is water found in blood, tissue fluid and lymph?
Yes! all 3
Are dissolved solids found in blood, tissue fluid and lymph?
Solutes it's to move freely between blood, tissue fluid and lymph
What's the first stage of the cardiac cycle?
The ventricles are relaxed and the atria contract which pushes blood through the atrioventricular valves to the ventricles