B3-B4 Flashcards
What is a tissue
A group of cells with a similar structure and function
What is an organ?
A collection of tissues performing a specific function
What is a organ system
A group of organs organised together to perform a function eg. The digestive system
What is an organism
Many organ systems working together to create an organism
What major organs make up the digestive system and state the functions
Mouth (breaks down food) Salivary glands (releases enzymes) Gullet Pancreas(enzymes) Stomach (digestion) Small intestine (digestion) Large intestine (transport Anus(release of waste)
What are carbohydrates made up of
Units of sugar
What happens to blue Benedict solution when a carbohydrate of only one or two sugars is heated in it?
It turns brick red
What sugar units are complex carbohydrates made up of
They are made up of chains of simple sugar units bonded together
What colour does starch change the yellow red iodine solution?
It turns black blue
What do lipids consist of
3 molecules of fatty acids bonded together with one molecule of glycerol
What does the ethanol test indicate
It indicates the presents of lipids
What are protein molecules made up of
They are made up of long chains of amino acids
When the blue biuret reagent is in the presence of protiens what colour does it change to
In the presence of proteins it turns purple
What do catalysts do
They increase the rate of chemical reactions
What are enzymes
Enzymes are biological catalysts that catalyse specific reactions in organisms due to their active site and lock and key mechanism
What what factors effect enzyme activity
It is affected by temperature and ph
What happens if the temperature is to high
The enzyme begins to denature and change shape
Where are protease enzymes found
Tye stomach
What conditions do the enzymes in the small intestine and pancreas need to work best at
They need alkaline conditions
What makes up the human circulatory system
The blood, blood vessels and the heart
What is the function if the human circulatory system
To transport substances to and from other body cells
What does plasma do
Plasma has blood cells suspended in it and transports proteins and other chemicals around the body
What does blood contain to allow to transport oxygen
Haemoglobin which binds the red blood cell with the oxygen
What do white blood cells do
They help protect against infection in the body
What are platelets
They are cell fragments that start clotting at wounded areas
What are the main type of blood vessels
Veins, arteries and capillaries
What happens to substances in capillaries
They diffuse in and out of the blood
What do valves in the heart prevent
They prevent back flow making it so the blood goes in the right direction
What is the name of the system that transports oxygen from mouth through heart to lungs
A double circulatory system
What are stents
They keep narrowed vessels open
What are statins
They reduce cholesterol levels and therefore reduce risk of coronary heart disease
What protects your lungs
Your rib cage
How have aviolli adapted to increase difusion
They have a large surface area and a rich supply of blood
What does xylem tissues transport
They transport mineral irons and water
What does the phloem tissues transport
They transport dissolved sugars
What is transpiration
The loss of water vapour from plant leaves
What do stomata and guard cells control
They control gas exchange and water loss
What factors effect photosynthesis
Temperature
Humidity
Air flow
Light intensity
