L1 - Cell Structure Flashcards
what are cells made up of?
organelles & cytoplasm
what surrounds the cell?
extracellular fluid
what marks the boundary between intracell and extracell?
plasma membrane (selectively permeable)
through where do ions enter and exit the cell?
via ion channels embedded in the plasma membrane
through where does water enter and exit the cell?
aquaporins
what are the three types of movement in the cell?
- diffusion
- facilitated diffusion
- active transport
what percent of the body is water?
50-60%
how is the water distributed?
1/3 in extracellular fluid and 2/3 in intracellular fluid
what is the function of the nervous system?
monitor the internal and external environment of the body - detecting changes via sensory receptors
how does the nervous system carry out its regulatory function?
the neurones’ ability to generate action potentials
what are the three types of neurones?
sensory, motor and interneurone
are neurones myelinated?
they can be either
what is the function of a neurone?
to transmit information around the body - by generating an electrical signal called an action potential