Answer:
The trachea, commonly known as the windpipe, is a most important organ as it allows the passage of air into the lungs. Because the trachea has a soft tissue tubular formation, it needs a base of stronger, yet flexible stuff that will give it support, protect it, and still allow the passage of air into the lungs.
This is precisely the task of the tracheal rings, or cartilage rings in the trachea. These rings are made out of cartilaginous tissue, which is much stronger than the soft tissue of the tubule, but are still flexible enough to not close down the tube when air is flowing in. Thus, the tracheal rings have two tasks: one, provide support and protection for the much softer and more vunerable tube of soft tissue through which the air passes, and two, provide flexibility so that air can flow easily.
If these tracheal rings did not exist, if they are crushed, or removed, a person´s trachea would simply collapse and the person would die as air would not be able to flow through to the lungs.
Answer: plants have roots, stems, or leaves
Algae and plants are similar organisms because both are autotrophic organisms which are able to produce their own food by the process of photosynthesis. The main difference between the two is the level of complexity. Algae are comparatively simple organisms, their structure ranges from single celled to multi-cellular organisms. They do not exhibit true roots, stems and leaves like plants. The plants exhibit complex specialized structure for transport of water, nutrients and to perform reproduction. The smallest to largest plant will exhibit roots, stems and leaves.
<h3><u>Answer;</u></h3>
D) frequently, and sometimes rapidly
<h3><u>Explanation;</u></h3>
- The hypothesis that the Grants have been testing was about the natural selection shaping the beaks of different bird populations.
- <em><u>The Grants documented that natural selection takes place in the wild finch population frequently, and sometimes rapidly.
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- The Grants' work showed that variation within a species increases the likelihood of the species' adapting to and surviving environmental change.
Answer: a. tRNA
Explanation: The transference RNA is a nucleic acid that participates of the protein synthesis. tRNA is a small RNA with folding as a trefoil. The tRNA has a site where aminoacid is loaded and a anticodon site that is complementary to the codon in the mRNA, ensuring the proper aminoacid sequence in the resulting polypeptide.
