<span>No.The involuntary muscles of the muscular system are not striated or furrowed.
</span>
<span><span>These muscles that are
not striated are very smooth to the sight which is why they are also
called Smooth muscles.</span> Involuntary muscles
are not striated. Even among the striated muscles that are voluntary,
the heart which is also a muscle, is involuntary.
On the other hand the striated muscles, which
are voluntary are highly fibrous and their primary function is to move
the body voluntarily, and producing heat as a result of this muscle
action.
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Lets understand the given passage.
An ecologist <u>observes that the diet of a bird species consists primarily of large grass seeds</u> (as opposed to smaller grass seeds or the seeds of other herbaceous plants found in the area).
<u>He hypothesizes that the birds are choosing the larger seeds because they have a higher concentrations of nitrogen than do other types of seeds at the site</u><u>.</u>
<u>To test the hypothesis, the ecologist compares the large grass seeds with the other types of seeds, and the results clearly show that the large grass seeds do indeed have a much higher concentration of nitrogen.</u>
No, he cannot conclude that the birds select the larger grass seeds because of their higher concentrations of nitrogen. The hypothesis testing done by the ecologist is incomplete as he failed to set up a control in the experiment. The control would have been the birds feeding on large seeds that lack or are low on nitrogen content. This will establish a relation between the bird's diet and the size of the seeds and the nitrogen content of the seeds. It could be true that birds do not care about the nitrogen content but simply prefer larger seed sizes.
Another problem associated with his field experiment is the failure in noting the beak sizes of the birds. The beak size and shape enable a bird to break and eat seeds. Larger beaks fail at breaking open smaller seeds. This observation would add bird beak size as another variable of the experiment.
Answer:
The elodea Cells do not burst because they have cell walls that keep them rigid.
Explanation:
With the exception of echinoderms, invertebrates are protostomes; chordates, echinoderms and vertebrates are deuterostomes.