U2 Key Area 6- Transport Systems In Animals Flashcards
How is carbon dioxide and oxygen transports
In mammals, nutrients, oxygen and carbon dioxide are transported in the blood
How is blood carried
By blood vessels
Where does the blood flow from
Blood flows from the heart to the lungs then from the heart to the whole body
What do valves do
Prevent the backflow of blood
Explain Why the walls of the left ventricle are much thicker than the walls of the right ventricle
The left ventricle has to pump blood all around the body whereas the right ventricle only has to pump blood to the lungs then from
Where do arteries carry the blood
Away from the heart
What type of blood to arteries contain
Mostly they contain oxygenated blood
Why do arteries have thick muscular walls
They have thick muscular walls which pulse to push the blood along
What size is an arteries channel (lumen in the middle)
Narrow
What pressure does the blood travel in the arteries
Blood in arteries travels at high pressure
Why is the blood pressure high in the arteries
The blood is under high pressure so that there is no risk of backflow as they do not have valves
Where do veins carry the blood
Into the heart
What type of blood do veins carry
They mostly carry deoxygenated blood
What type of walls do veins have
They have thin muscular walls and a wide lumen (or centre channel)
What pressure do blood travel at in veins
This means blood in veins travels at at a low pressure
What’s the problem of veins having low blood pressure
Due to the low blood pressure there is a risk of backflow of blood, so they have valves to prevent this from happening
What size are capillaries
Capillaries are microscopic blood vessels
What do the capillaries connect
They connect to arteries to the veins
What are capillaries and what does it allow
They are branched networks which cover a large surface area of tissues and organs. This allows for rapid diffusion of materials to and from blood.
What size are capillaries walls and why
Their walls are one cell thick to allow materials to diffuse quickly from and to blood
Why are red blood cells specialised in their structure
Red blood cells are specialised in their structure so that they can carry oxygen efficiently in the form of oxyhaemoglobin
What do red blood cells have and why (3)
- A bioncave shape to increase the surface area over which oxygen can bind
- no nucleus so that they can contain more haemoglobin
- haemoglobin which combines with oxygen to form oxyhaemoglobin
What are white blood cells
White blood cells are part of the immune system and are involved in destroying pathogens
Pathogens
Pathogens are biological agents that cause disease or illness to their host
There are two main types of white blood cells involved
Phagocytes
Lymphocytes
What do phagocytes do
Phagocytes carry out phagocytosis by engulfing bacteria
How do phagocytes carry out phagocytosis in detail
- Phagocytes recognise molecules on the bacteria’s surface.
- They bind with the bacterium and engulf it
- Once the bacterium is inside the phagocyte, lysosomes help to digest the bacterium
What do some lymphocytes produce
Proteins called antibodies
What are antibodies
Antibodies are proteins that destroy pathogens
Each antibody is….
Specific to a particular antigen
What happens when the antibody binds to its specific antigen
This inactivates the pathogen and makes it more susceptible to phagocytosis
