Cells in organisms Cells are the building blocks of all living things
Euglena have only one cell. They live in water and make their own food from sunlight.
Multicellular organisms. • Humans contain many different cells for various functions. • Red blood cells carry oxygen • Muscle cells move bones and organs • Nerve cells conduct messages • Stomach lining cells make digestive juices • Cells are studied with a microscope
Setup • Adjust the mirror to maximise the light • Rotate the lowest power lens (the shortest) above the hole in the stage • Place object (eg slide) above hole • Turn focussing knob till lens just above hole (view this from the side) • View through eyepiece and wind objective lens away from stage till focussed.
Wet slide • Letter e should be reversed