15 Control and coordination
All the activities of multicellular organisms require coordinating, some very rapidly and some more slowly. The
nervous
... [Show More] system and the endocrine system provide coordination in mammals. Coordination systems also exist in
plants.
15.1 Control and coordination in
mammals
Learning outcomes
Candidates should be able to:
1 describe the features of the endocrine system with reference to
the hormones ADH, glucagon and insulin (see 14.1.8, 14.1.9 and
14.1.10)
2 compare the features of the nervous system and the endocrine
system
3 describe the structure and function of a sensory neurone and a
motor neurone and state that intermediate neurones connect
sensory neurones and motor neurones
4 outline the role of sensory receptor cells in detecting stimuli and
stimulating the transmission of impulses in sensory neurones
5 describe the sequence of events that results in an action
potential in a sensory neurone, using a chemoreceptor cell in a
human taste bud as an example
6 describe and explain changes to the membrane potential of
neurones, including:
• how the resting potential is maintained
• the events that occur during an action potential
• how the resting potential is restored during the refractory
period
7 describe and explain the rapid transmission of an impulse in a
myelinated neurone with reference to saltatory conduction
8 explain the importance of the refractory period in determining
the frequency of impulses
9 describe the structure of a cholinergic synapse and explain how
it functions, including the role of calcium ions
10 describe the roles of neuromuscular junctions, the T-tubule
system and sarcoplasmic reticulum in stimulating contraction in
striated muscle
11 describe the ultrastructure of striated muscle with reference to
sarcomere structure using electron micrographs and diagrams
12 explain the sliding filament model of muscular contraction
including the roles of troponin, tropomyosin, calcium ions and
ATP
15.2 Control and coordination in
plants
Learning outcomes
Candidates should be able to:
1 describe the rapid response of the Venus fly trap to stimulation
of hairs on the lobes of modified leaves and explain how the
closure of the trap is achieved
2 explain the role of auxin in elongation growth by stimulating
proton pumping to acidify cell walls
3 describe the role of gibberellin in the germination of barley (see
16.3.4) [Show Less]