B2 Organisation Flashcards
What are cells?
The basic building blocks of life
What is a tissue?
A group of cells with a similar structure and function
What are organs?
Aggregations of tissues performing specific function
What are organs organised into?
Organised into organ systems which work together to form organisms
What is the digestive system?
An example of an organ system in which several organs work together to digest and absorb food
What are enzymes?
Biological catalysts
What do enzymes control?
Metabolism , that is the sum of all the reactions in a cell or in the body
What is the lock and key theory?
The key is the substrate the lock is the enzyme and the key hole is the active site
When the substrate the substrate and enzyme are in place they bind together and break down
What is amylase?
The enzyme that breaks down carbohydrates (starch)
What is lipids?
The enzyme that breaks down fats into fatty acids and glycerol
What do digestive enzymes convert?
They convert food into small soluble molecules that can be absorbed into the bloodstream
What do carbohydrates do?
They break down carbohydrates to simple sugars .
Amylase is a carbohydrase which breaks down starch
What is protease?
The enzyme that breaks down proteins into amino acids
What are the
What are the products of digestion used for.
They are used to build new carbohydrates,lipids and proteins. Some glucose is used in respiration
What are the products of digestion used for.
They are used to build new carbohydrates,lipids and proteins. Some glucose is used in respiration
What is made in the liver?
Bile is made in the liver and stored in the gall bladder
What is bile?
It is an alkaline to neutralise hydrochloric acid from the stomach. It a,so emulsifies fat to form small droplets which increase the surface area . These increase the rate of fat breakdown by lipase
What is blood?
Blood is a tissue consisting of plasma , in which the red blood cells ,white blood cells and platelets are suspended
What are red blood cells?
They are cells that pick up oxygen from the air in your lungs and carry it to cells where it is needed
What are the adaptations of red blood cells?
They are bioconcave discs giving them an increased surface area to volume ratio for diffusion
They pascked with a red pigment called haemoglobinthat binds to oxygen
They have no nucleus making more space for haemoglobin
What are white blood cells?
What are platelets
They are small fragments of cells
Do platelets have a Nucleus ?
No
Why are platelets important ?
They are very important in helping the blood to clot at the site of a wound
What is blood clotting?
A series of enzyme-controlled reactions that result in fibrinogen into fibrin. This produces a network of protein fibres that captures lots of red blood cells and more platelets that stops u from bleeding to death
What happens after the blood clot dries?
It hardens to form a scab which protects the new skin as it grows and stops bacteria entering the body
What do white blood cells do?
They have a nucleus and form part of the bodies defence system against harmful microorganisms. Some form antitoxins yet others engulf and digest the invading bacteria and viruses
What are the types of blood vessels?
Arteries veins capillaries
What do arteries do?
They carry blood away from your heart to the organs of ur body
What do veins do?
They carry blood away from your organs to the heart
What do capillaries do?
They form a huge network of tiny vessels linking the arteries and veins