(1) The varying number of muscle fibers that contract
<span>In most muscles, the number of muscle fibers in different motor units ranges from a few to hundreds. The nervous system can thus regulate the strength of contraction in a muscle by determining how many motor units are activated at a given instant and by selecting large or small motor unties to activate. </span>
some muscles are almost always partially contracted. In such muscles, the nervous system my alternate activation among the motor units, reducing the length of time any one set of fibers is contracted. Prolonged contraction can result in muscle fatigue due to the depletion of ATP and dissipation of ion gradients required for normal electrical signals.ing.
<span>(2) varying the rate at which muscle fibers are stimulated </span>
<span>single action potential produces a twitch lasting about 100 msec or less. If a second action potential arrives before the muscle fiber has completely relaxed, the two twitches add together, resulting in greater tension. Further summation occurs as the rate of stimulation increases. When the rate is so high that the muscle fiber cannot relax at all between stimuli, the twitches fuse into one smooth, sustained contraction called tetanus.</span>
<span>The best and most correct answer among the choices provided by the question is the first choice. A decrease on the pine trees would decrease the number of the woodpeckers. <span>I hope my answer has come to your help. God bless and have a nice day ahead</span></span><span>
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Animals can defend themselves against predators and extreme weather by adapting. Numerous birds may conceal themselves under long grass, while weeds, insects, and other creatures can alter their color to blend in. Predators find it challenging to locate them in search of food as a result.
<h3>What are species?</h3>
A species is a unit of biodiversity as well as the fundamental classification and taxonomic rank of an organism in biology. The biggest group of organisms in which any two individuals of the right sexes or mating types can conceive a fertile offspring, usually by sexual reproduction, is referred to as a species. A species can also be identified by its karyotype, DNA sequence, anatomy, behavior, or ecological niche. In addition, since fossil reproduction cannot be studied, paleontologists use the chrono species idea.
<h3>What are the different types of species?</h3>
- Typological Species
- Nominalistic Species
- Biological Species
- Evolutionary Species
- Taxonomic Species.
- Microspecies.
- Biological Species.
- Evolutionary Species.
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Real number : 8394000000
scientific notation : 8.394 x 10^9
Answer:
Colin MacLeod, and Maclyn McCarty showed that DNA (not proteins) can transform the properties of cells, clarifying the chemical nature of genes.
Explanation:
