cell organisation Flashcards
what are large multicellular organisms made up of?
organ systems
what is a specialised cell?
a cell made to carry out a particular function
what is differentiation?
the process where cells become specialised for a particular job. It occurs during the development of multicellular organisms
what do specialised cells form?
tissues which form organs which form organ systems
what do large multicellular organisms have inside them?
different systems for exchanging and transporting materials
what is a tissue?
a group of similar cells that work together to carry out a particular function it can include more than one type of cell
what are examples of tissues in mammals?
muscular tissue, which contracts to move whatever it’s attached to
glandular tissue, which makes and secretes chemicals like enzymes and hormones
epithelial tissue, which covers some parts of the body e.g. inside gut
what is an organ?
a group of different tissues that work together to perform a certain function
what tissues is the stomach made up of?
muscular tissue, moves stomach wall to churn up food
glandular tissue, makes digestive juices to digest food
epithelial tissue, covers the outside and inside of the stomach
what is an organ system?
a group of organs working together to perform a particular function
what is an example of an organ system?
digestive system, breaks down and absorbs food
made up of:
glands(pancreas and salivary glands) which produce digestive juices
stomach and small intestine, which digest food
liver, which produces bile
small intestine, absorbs soluble food molecules
large intestine,absorbs water from undigested food, leaving feeces
what do organ systems work together to make?
entire organisms
what are enzymes
catalysts produced by living things
how could you usually make a reaction happen more quickly
raising the temperature, this would speed rate of useful reactions but also bad ones, there is also a limit to how far you can raise the temperature inside a living creature without damaging its cells
what do living things produce as biological catalysts
enzymes which reduce the need for high temperatures and we only have enzymes to speed up useful reactions in the body
what is a catalyst?
a substance which increases the speed of reaction, without being changed or used up
what are enzymes made up of
they are all large proteins and all proteins are made up of chains of amino acids these chains are folded into unique shapes, which enzymes need to do their jobs
why do enzymes have special shapes?
so they can catalyse a reaction
what do chemical reactions usually involve?
things being split apart or joined together
what does every enzyme have?
an active site with a unique shape that fits onto the substance involved into a reaction
how many reactions do enzymes usually catalyse
one specific reaction
why do enzymes only catalyse one specific reaction?
because for the enzyme to work the substrate has to fit into its active site, if the substrate doesn’t match the enzymes active site then the enzyme will reaction won’t be catalysed
what is the induced fit model?
the active site changes shape a little as the substrate binds to it to get a tighter fit
what is lock and key
how enzymes active site and substrate fit perfectly with eachother