The System of Flexing and Extending Muscles Makes Movement of Appendages

question 37

Multiple Choice

The system of flexing and extending muscles makes movement of appendages easy to understand. But how are some actions possible (sticking out your tongue, beating of your heart) when these structures have no bone structure with opposing flexors and extensors in them?

• A) One set of muscle cells must therefore be able to both contract and expand.
• B) These structures must be empty chambers, and fluids forced into them expand them.
• C) Since muscle cells can only contract and relax, muscle cells running diagonally or crosswise amidst the longitudinal muscles must contract and force the long relaxed muscle cells to elongate.
• D) This cannot be explained at present.

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Definitions:

Population Distribution

The distribution of a characteristic within an entire population, described by parameters such as mean, variance, and standard deviation.

Null Hypothesis

A hypothesis that suggests there is no statistical significance between two variables, often used as a default hypothesis in testing.

Standard Deviation

A measure of the dispersion or spread of a set of values, indicating how much the values deviate from the mean of the data.

Test Statistic

A value calculated from sample data during a hypothesis test used to decide whether to reject the null hypothesis.