There are three types of muscle tissue<span>: Visceral, </span>cardiac<span>, and </span>skeletal<span>. </span>Visceral Muscle<span>. </span>Visceral muscle<span> is found inside of organs like the </span>stomach<span>, intestines, and </span>blood vessels. The major types of muscle systems are the skeletal muscles, cardiac muscles and smooth muscles.<span> The skeletal muscles are voluntary muscles, whereas the smooth and cardiac muscles are involuntary ones.</span>
<span>C. metric ruler since millimeters are metric</span>
The nucleus contains <u>protons</u> and <u>neutrons</u><u>,</u> giving it an overall <u>positive</u> charge.
Answer:
Most cells within planarians tend to be very close to their gastrovascular cavity, in addition to their external environments. Also, planarians have the ability for oxygen and carbon dioxide to diffuse through the cells on their body walls: this makes it unnecessary for these varieties of flatworms to need a dedicated bodily system.
I think the deficiency of dedicated respiratory and circulatory systems in Planarians does not cause a problem because none of their cells are far removed from the gastrovascular cavity or from the external environment. Planarians are free-living flatworms and form the class Turbellarians in the Phylum Platyhelminthes. Flatworms have three tissue layers, that is the ectoderm, mesoderm, and endoderm.
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Explanation:
