A series of four figures is shown along side. Study them carefully. These depict an important phenomenion found in plant cells. Answer the questions that folie
(a) Name the phenomenon depicted in the series of figures A to D
b) Label the parts 123 (d The figure is the normal cell. What made the cell contents to behave in
the way they did in the series of
figures A to D.
(dlf the cell shown at stage in D is placed in distilled water, what do you think is likely to happen and why? (e) Name the phenomenon that may take place when the cell D is placed in distilled water.
Answers
i) The phenomenon that is depicted here is the reflex action which is an involuntary and instant movement in response to stimuli.
(ii) The term for the point of contact between the two nerve cells is called the synapse.
(iii) (1). Sensory (Afferent neuron) (2). Dorsal ganglion
(3). White matter (4). Grey matter
(iv) The function of 5 (Synapse): It transmits the sensory impulse from sensory neurons to the motor neurons.
The function of 6 (Motor neuron/Efferent neuron): It transmits the command to the effectors part (e.g. muscles).
v) The arrangement of neurons in the spinal cord differs from that of the brain. In the brain, Gray matter is present on the outside and white matter on the inner side. In Spinal cord, white matter is present on the outside and Gray matter on the inner side.