Experiments with Invertibrates

Electrocardiography

Why do we find a cellar warm in winter but pleasantly coolin summer?

Electromyography

We investigate our muscular power - electromyography

Principle

With the exception of the heart muscle, the contractions of striated muscles can be controlled at will. This characteristic enables the observation of the activities of individual muscle groups. An electromyogram (EMG) can be used to measure (record) ...

Electrooculography

Mechanical stimulation at the front end of earthworm

Electrical stimulation of an anaesthetised earthworm

Muscle stretch reflex and determination of the conductingvelocity

Recording of nerve and muscle potentials by mechanical stimulation at the rear end of an earthworm (Cobra3)

Principle and tasks

To work on the following themes by measuring nerve and muscle potentials:

• the course of a biphasic action potential over time
• estimation of the conduction velocity
• coding of the stimulant intensity as frequency modulation ...

Recording of nerve and muscle potentials by mechanical stimulation at the front end of an earthworm (Cobra3)

Principle and tasks

To work on the following themes by measuring nerve and muscle potentials:

• The difference in sensitivity of the front and rear ends
• The facilitation effect
• Conduction velocity and fibre diameter
• Synaptic depress ...

Recording of nerve potentials after the electrical stimulation of an anaesthetised earthworm (with the Cobra3 Basic-Unit

Principle and tasks

To work on the following themes by measuring nerve and muscle potentials:

• The action of an anaesthetic
• The different conduction velocities of median and lateral giant fibres
• Refractory period of the median giant fibre

Electromyography (EMG) on the upper arm (with the Cobra3 Basic-Unit)

Principle and tasks

To prepare an electromyogram (EMG) from a contracting or relaxing upper arm muscle (biceps) using surface electrodes. Measurement of the frequency and the amplitude of the EMG at maximum concentration.

What you can learn about

Muscle stretch reflex and determination of the conducting velocity (with Cobra3 Basic-Unit)

Principle and tasks

To trigger a stretch reflex in the lower leg musculature by tapping the Achilles tendon (Achilles tendon reflex). To record the compound action potential and determine the reflex latency and the conduction velocity.

What you can learn about< ...