Unit 2 - Key Area 6 - Transport Systems In Animals Flashcards
What is the function of blood?
Blood transports nutrients, oxygen, and carbon dioxide around the body and helps fight infections.
What is the function of red blood cells?
Carry oxygen
What is the function of white blood cells?
Help to fight infection
What is the function of plasma?
Carries nutrients (glucose and amino acids), carbon dioxide, and wastes.
What is the importance of a biconcave disc shape?
Red blood cells have a biconcave disc shape to increase the surface area for carrying oxygen.
What is the importance of having no nucleus?
They have no nucleus which makes space for carrying more oxygen.
What is the importance of pigment haemoglobin?
They have a large volume of haemoglobin to carry oxygen.
Describe the relationship between oxygen and haemoglobin
Haemoglobin binds with oxygen at a high concentration (in the lungs) and forms oxyhaemoglobin.
Haemoglobin + Oxygen → Oxyhaemoglobin
Haemoglobin releases oxygen (in the cells) where the oxygen concentration is low
Oxyhaemoglobin → Haemoglobin + Oxygen
The oxygen then diffuses into the cells.
What are white blood cells?
White blood cells are part of the immune system and are involved in destroying pathogens.
What are pathogens?
Pathogens are disease causing micro-organisms (bacteria, viruses and fungi).
Describe the function of phagocytes
Phagocytosis (cell eating) by engulfing and digesting pathogens.
Describe the function of lymphocytes
Produce antibodies which destroy pathogens. Each antibody are specific to a particular pathogen.
What is the direction of arteries
Away from the heart
What is the direction of veins
Back to the heart
Why does the heart contain valves?
The heart contains valves to prevent the back flow of blood.
What do the coronary arteries do?
The heart muscle cells are supplied with blood by the coronary arteries. These are the first arteries to branch off from the aorta.
Blockage of the coronary arteries can deprive part of the heart muscle of oxygen, causing it to die.
Describe arteries
Thick muscular walls
Narrow central channel
Carry blood under high pressure AWAY from the heart
Describe capillaries
Thin walled to allow efficient exchange of materials
Capillaries form networks through organs and tissues and have a large surface area
Describe veins
Thin muscular walls
A wide central channel
Carry blood under low pressure to the heart
Contain valves to prevent backflow of blood
Describe the blood vessels
Arteries divide up into capillaries, which then join up to make veins.
Describe the pathway of blood around the body
Oxygenated Blood:
Vena Cava → Right Atrium → Right Ventricle → Pulmonary Artery → Lungs →
Deoxygenated Blood:
Pulmonary Vein → Left Atrium → Left Ventricle → Aorta → Body
