Answer:
They form crystals
They have high melting points and high boiling points
They have higher enthalpies of fusion and vaporization than molecular compounds
They're hard and brittle
They conduct electricity when they are dissolved in water
They're good insulators
Explanation:
i hope this is what you need
Answer:
The correct answer is A. The larynx moves up against epiglottis when food is swallowed to prevent passage of food into it.
Explanation:
The epiglottis is a moist, cartilaginous structure that is part of the cartilaginous skeleton of the larynx. It also marks the boundary between the oropharynx and the laryngopharynx. The epiglottis obstructs the passage of the bolus at the time of swallowing preventing it from going to the respiratory system.
Larynx closure occurs when the vestibular and vocal folds approach the midline during swallowing. Occasionally, when you eat very fast, solid foods or liquids can enter the larynx.
Answer:
The short answers are Yes, it's random, and Yes, it "waits" for some time.
Different tRNA's just float around in the cytoplasma, and diffuse more or less freely around. When one happens to bump into the ribosome, at the right spot, right orientation, and of course which has an anticodon matching the codon in frame of the mRNA being translated, it gets bound and takes part in the synthesis step that adds the amino acid to the protein that is being synthesized.
The concentration of the various species of tRNA is such that translation occurs in a steady fashion, but there is always some waiting involved for a suitable tRNA to be bound. In that waiting time, the ribosome and mRNA stay aligned - that's because the energy that is required to move the to the next position is delivered as part of the same chemical reaction that transfers the amino acid from the tRNA to the protein that is being synthesized.
I'm not entirely sure what happens if there is significant depletion of a particular species of tRNA, but I think it's likely the ribosome / RNA complex can disassemble spontaneously. But spontaneous disassembly can't be something that occurs very easily after translation was initiated, since we would end up with lots of partial proteins which I expect would be lethal very soon.
(Can't know for sure though, but it would be very hard to set up an experiment to measure just what will happen and even if you got a measurement it would be hard to figure out how it applies to normal, living cells. I can't imagine tRNA depletion occurs in normal, healthy living cells.)
The answer is 3
Synthesize enzymes from organic molecules
