State the word which is used to describe a pair of muscles that act against each other to perform opposite actions.Â
Classify the following alphabetical list of organisms into their skeleton type in the table below.Â
- Amphibians
- Arachnids
- Birds
- Centipedes
- Crustaceans
- Fish
- Insects
- Mammals
- Molluscs
- Reptiles
Internal Skeletons | Exoskeletons |
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The diagram shows a myofibril strand in a relaxed muscle fibre.
Describe the effect of muscle fibre contraction on the length of the A-band and the sarcomere.
Explain the presence of a large number of mitochondria in the sarcoplasm of a muscle fibre.Â
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