Primary Succession is when an ecological community experiences a community changing natural disaster (volcano, glacier, etc) primary succession starts from bare rock. Secondary succession starts from pre-existing soil, and occurs from a hurricane, deforestation, etc.
Do you have a picture or something?
Answer: muscle contraction of sustained force resulting from repeated action potentials. (Option A)
Explanation: Tetanus is also called physiologic tetanus. Tetanus refers to the contraction of the muscle, which is established when the motor nerve that supply nerves to a skeletal muscle produces action potentials at a very high degree.
However, tetanic contraction is usually a normal process (such as when carrying a heavy box). Also, muscles can be shorten, lengthen or remain constant length during tetanic contractions.
