mitosis/stem cells/the nervous system Flashcards
mitosis
Mitosis is a type of cell division in which a cell copies itself and divides into two identical daughter cells.
interphase
The cell spends most of its life in this phase. The DNA in chromosomes copies itself ready for mitosis.
prophase
the nucleus starts to break down and spindle fibres appear
metaphase
the chromosomes are lined up on the spindle fibres across the middle of the cell
anaphase
the chromosome copies are split up and moved to either end of the cell
telophase
a membrane forms around each set of chromosomes to form nuclei
cytokenesis
a cell surface membrane forms to separate the 2 cells
growth
increase in size as a result in an increased number of cells
stem cells found in plants
meristems
stem cells found in the embryo
embryonic stem cells
stem cells used for tissue growth and replacement of damaged cells
adult stem cells
what makes up the nervous system
the central nervous system, the spinal chord
neurotransmission
the transmission of impulses
direction of impulse through a receptor cell
dendrite (receives impulses from receptor cells), dendron, cell body, axon, axon terminals (passes impulses to other neuron)
motor neuron
carries impulses to the effectors
effectors
carries out an action that is recieved from the impulse
relay neuron
found in the spinal cord, where they link motor and sensory neurones
what do reflex arcs do
bypass parts of the brain involved with processing information to create quicker responses
synapses
small gaps between neurones
why are synapses used
to keep the flow of impulses in one direction
what is the direction of the reflex arc
the reflex arc goes straight to the spinal cord and then to the muscle
