Animal Transport systems Flashcards
What three parts is the mammalian circulatory system composed of?
The circulatory system is a transport system which is composed of three main parts:
Blood, the liquid which is transported all around the body.
The heart (the pump)
The blood vessels (tubes which carry fluid around the body)
What is the job of the blood?
The job of the blood is to transport nutrients (from the digestive system) and oxygen (from the lungs) to respiring cells. In addition, it transports carbon dioxide from respiring cells to the lungs.
What does a mammal’s blood contain?
A mammals blood contains two types of cells:
Red blood cells
White blood cells
and a watery fluid called plasma.
What percentage does plasma make up of our blood?
Plasma makes up about 55% of your blood.
What is the function of plasma?
Its function is to carry dissolved substances around the body. These include:
Chemical messengers or hormones, such as insulin.
Proteins such as antibodies
The soluble end products of digestion, e.g. glucose and amino acids.
Gases such as carbon dioxide.
What are the specialisations in red blood cells?
Red blood cells are specialised by:
Being small and flexible
Containing haemoglobin and having no nucleus
Having a biconcave disc (being biconcave in shape)
How many red blood cells are in our blood?
Your blood contains a huge number of red blood cells; in fact each ml/cm3 of blood contains 5.5 million cells.
How does red blood cells being small and flexible aid oxygen transport to cells?
Red blood cells are very small and flexible so that they can squeeze through even the narrowest blood vessels called capillaries.
What is the function of red blood cells?
Their function is to transport and release oxygen to respiring cells.
How does red blood cells containing haemoglobin and no nucleus aid oxygen transport to cells?
For red blood cells to carry out their job, they contain a protein substance called haemoglobin. The fact that red blood cells do not have a nucleus means they can contain lots of haemoglobin to transport oxygen.
How does red blood cells having a biconcave shape aid oxygen transport to cells?
Red blood cells have a biconcave shape which provides a large surface area, allowing them to absorb more oxygen (by diffusion) and, therefore, transport more oxygen to respiring cells.
What is haemoglobin?
Haemoglobin is a protein molecule found in red blood cells in blood vessels.
When does haemoglobin form oxyhaemoglobin?
Haemoglobin can easily join with oxygen in areas of the body where there is a high oxygen concentration, for example in the lung capillaries. When haemoglobin chemically combines with oxygen oxyhaemoglobin is produced.
When and how does oxyhaemoglobin release oxygen to cells?
When oxyhaemoglobin reaches areas of the body where oxygen concentration is low, e.g. respiring cells, oxyhaemoglobin will quickly release the oxygen, which then diffuses into the cells.
Write the word equation for oxygen combining with haemoglobin?
haemoglobin + oxygen ⇌ oxyhaemoglobin.
the reaction is reversible
What systems are white blood cells a part of?
White blood cells are part of our immune system.
What is the function of white blood cells in our body?
White blood cells are in our bodies in order to destroy pathogens entering the body.
What is a pathogen?
A pathogen is a disease-causing micro-organism.
Name three different pathogens.
Three types of pathogens are: bacteria, viruses and fungi.
What are two types of white blood cells that destroy pathogens?
Two types of white blood cells that destroy pathogens are known as phagocytes and lymphocytes.
Describe a phagocyte and its function.
A phagocyte is a type of white blood cell that kills microorganisms by engulfing and digesting them during a process called phagocytosis.
What are the shapes on pathogen surfaces recognized by?
Every pathogen has unique shapes (antigens) on its surface. These shapes are recognised by lymphocytes.