The simplest answer is that these all have a backbone/notochord and all have internal skeletons of some type,
The phenomenon of populations of organisms changing from generation to generation is known as biological evolution.
<h3>What is biological evolution?</h3>
Biological evolution is a scientific term that deals with the change in inherited traits through successive generations in an organism's population. For example, penguins have typical wings over swim-friendly flippers which were there for many generations. It is also called microevolution. Biological evolution is important because it helps us to understand why an organism is the way they are. Mutation, genetic drift, gene flow, and non-random mating are some of the causes of biological evolution. Heredity and Reproduction are the top conditions for biological evolution.
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Answer:
1. Isometric contraction is best defined as a contraction that is not associated with any movement. It can be used by the therapist to increase strength and elasticity.
An example of an isometric contraction is carrying an object in front of you. The weight of the object would be pulling downward, but your hands and arms would be opposing the motion with equal force going upwards. Since your arms are neither raising or lowering, your biceps will be isometrically contracting.
2.
a. At threshold just a few muscle fibers are being recruited.
b. At the maximal stimulus is 100% of recruitable fibers are contracting.
c. Above maximal stimulus, the number of contracting fibers cannot increase.
Explanation:
