Animals exhibit variations in any physical or chemical process required for cells as a collective unit of the muscle system to carry out their normal functions or activities or be able to perceive and respond to stimuli, compared to control animals.
Animals die during embryonic development. In C. elegans, often assayed as refractile eggs that fail to hatch; when applied to large-scale RNAi screens in C. elegans, more than 10% of embryos die.