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Table 16-7-1







Relay neurone

Cell body in root cell ganglion


Sensory neurone

Motor neurone

No axon


Relay neurone

Gland, muscle
(effector organ)

Schwann cells

Change In Membrane Permeability Leading To The Generation Of An Action Potential

The Role Of The Neurone Membrane In The Establishment Of A Resting Potential

The All-Or Nothing Nature Of Nerve Impulses

Refractory Period

Factors Affecting the Speed of Conductance: Myelin, Axon Diameter, Temperature

Synaptic Transmission

Aspects Of Synaptic Transmission

The Mechanisms Of Transmission At An Excitatory Synapse

Knowledge Of Transmitters Limited To Acetylcholine And Noradrenaline

The Agonistic And Antagonistic Effects Of Chemicals On Synaptic Transmission

Spinal Reflexes

The Pathway and Adaptive Value of a Simple Spinal Reflex Involving 3 Neurones

Autonomic Nervous System (ANS)

Outline of the Functions of Parasympathetic and Sympathetic Divisions of the ANS

Table 16-10-1: The ANS controls internal glands + muscles beyond conscious control

Target Organ/Tissue
Effect on organ:
Motor neurone releases:

Parasympathetic Stimulation
Inhibitory effect / relaxation
Acetylcholine (ACh)

Sympathetic Stimulation
Excitatory effect / stress
Norepinephrine (noradrenlaine)

Iris of eyes

Constricts pupil

Dilates pupil

Bronchi, bronchioles

Constricts tubes

Dilates tubes

Blood vessels

- Dilates blood vessel
- Lowers blood pressure

- Constricts blood vessels
- Raises blood pressure


- Lowers heart rate
- Lowers stroke volume

- Raises heart rate
- Raises stroke volume

Intercostal muscles

Lowers breathing rate

Raises breathing rate

Salivary glands

Stimulates secretion of salvia

Inhibits secretion of salvia


Stimulates peristalsis

Inhibits peristalsis

Sweat glands

No effect

Increases sweat production


Specific Physiology in the Context of the Control of Heart Rate