Summary Topic 14 - Control & Coordination

14.1 - Control and Co-ordination in
Mammals
NERVOUS VS ENDOCRINE SYSTEM

Mammalian nervous system - central nervous system (brain and spinal cord) + peripheral nervous
system (cranial and spinal nerves)

Differences

Nervous Endocrine

Communication Impulse Hormone

Nature of Electrical (and Chemical
Communication chemical)

Mode of Transmission Neurone (synapse) Blood

Response Destination Muscle/gland (effector) Target organs (receptor on cell surface
membrane)

Transmission Speed Faster Slower

Effects Localised Widespread

Response Speed Faster Slower

Duration Short-lived (temporary) Long-lasting (permanent)

Receptor Location Cell surface membrane Cell surface membrane or within cell

*Similarities

Cell Signaling Both involve cell signaling

Detail Both involve signal molecule binding to receptor

Chemicals Both involve chemicals

,NEURONES

SENSORY NEURONE

1.Transmit impulses from sensory receptors to the central nervous system (CNS)

 Cell body in middle of axon
 Nucleus in cell body
 Long dendron
 Shorter axon
 Many mitochondria (in cell body)
 Many RER (in cell body)
 Synaptic knobs
 Terminal dendrites
 Schwann cells
 Myelin sheath - covers some of length, made by Schwann cells
 Nodes of Ranvier




MOTOR NEURONE

3.Transmit impulses from the CNS to the effectors (muscles and glands)

 Cell body at one end of axon
 Nucleus in cell body
 Short dendron
 Long axon
 Many mitochondria (at synaptic knob)
 Many RER (in cell body)
 Synaptic vesicles
 Schwann cells - make myelin sheath
 Node of Ranvier
 Dendrites have receptors for neurotransmitters

, RELAY NEURONE

2.Pass impulses on to the motor neurone

 Found in the central nervous system




Name of Cell Part Function/Description of Cell Part
Mitochondria Providing ATP for active transport



Nucleus Control the functions of the nerve cell and contains cell's DNA



Dendrites Connect to other neurones or receptors - carry information towards cell
body

Cell Body Where most of the processes take place - e.g. metabolism



Myelin Sheath Lipid covering around the axon of a neurone - insulates axon



Schwann Cell Surround the axon - form the myelin sheath