Expert: John Locke - 3/6/2009

Question
Im Dislexic abd Im home schooled and Im terrible with science.  This is one of my test.  Could you please go over it and tell me which answers are wrong?

Question
1. All except three codons provide codes for amino acids. These three codons are used as _______ signals.

 A. speed-up
  B. stop
  C. slow-down
  D. go
   
C   
   
2. Units of actin and myosin are arranged end to end in order to

 A. form a muscle cell.
  B. produce actin-myosin bonds.
  C. activate actin molecules.
  D. separate actin from myosin.
  
A    
   
3. In the double helix shape of DNA, what series of nucleotides would match the nucleotide series G-A-C-T?

 A. A-G-T-C.
  B. C-T-G-A.
  C. T-C-A-G.
  D. A-C-G-A.
      
D  
 
4. Which one of the following statements best expresses the concept of emergence in organisms?

 A. Growth patterns, such as those of a beehive, are a sum of various parts.
  B. Simple units don't follow simple rules.
  C. The multiplication of many interactions produces an overall product.
  D. The true meaning of any organization can be seen in each of its individual parts.
   
B   
   
5. Which one of the following statements regarding proteins is true?

 A. The sequence of amino acids in a protein chain molecule defines its shape, but not its function.
  B. Water-liking molecules of amino acids in a protein chain molecule tend to stay on the outside surface where they can do their work.
  C. Proteins are chain molecules consisting of different linking molecules for each amino acid.
  D. Fat-liking amino acids turn outward and join together in strong bonds.
 
B     
   
6. Louis Pasteur's experiments brought to an end the theory of _______ generation.

 A. spontaneous
  B. vital
  C. life
  D. experimental
      
C
   
7. Which one of the following types of molecules serves to interact with the world around us?

 A. DNA
  B. RNA
  C. Proteins
  D. Ribosomes
     
A
   
8. Your job among enzymes on the DNA replication team is to keep single DNA strands from getting tangled. You're a complex of four protein subunits called a(n)

 A. initiator.
  B. untwister.
  C. straightener.
  D. stitcher.
    
C  
   
9. The inheritance factors hypothesized by Gregor Mendel came to be called

 A. chromosomes.
  B. genes.
  C. traits.
  D. mutations.
    
A  
   
10. What happens to an allosteric enzyme when the concentration of substrate around the molecule increases?

 A. It becomes essentially non-functional.
  B. It increases its processing capacity.
  C. The substrate binding sites become inaccessible.
  D. It becomes less sensitive to the action of signal molecules.
   
C   
   
11. What enzyme is present in cancer cells, which, scientists believe, allows the cancer cells to keep growing indefinitely?

 A. Morphogen
  B. Glucagon
  C. Oxytocin
  D. Telomerase
      
C
   
12. Which one of the following parts by itself can carry no information?

 A. Genome
  B. Chromosome
  C. Codon
  D. Nucleotide
     
D
   
13. The process by which a web-spinning spider makes a "sketch" of a web design before making the permanent web is called

 A. lock-step sequence.
  B. simulation.
  C. trial and error.
  D. cinch and attach.
      
A
   
14. To make a specific protein, ribosomes, a set of twenty strands of tRNA, and a strand of messenger RNA work together in a process called

 A. translation.
  B. transcription.
  C. replication.
  D. reproduction.
      
D
   
15. Through a series of experiments with sterilized broth, Louis Pasteur disproved the idea of

 A. gene sequencing.
  B. DNA fingerprinting.
  C. spontaneous generation.
  D. evolution.
      
C
   
16. In the telophase stage of mitosis, microtubules gather along the cell's equator. The purpose of these microtubules is to

 A. supply nutrients to the cell as it burns more energy.
  B. protect the cell's two groups of chromosomes.
  C. form spindle fibers that duplicate the cell's DNA.
  D. assemble materials that will form the new cell wall.
    
B  
   
17. When the repair mechanism for DNA fails, the result is a

 A. weak bond.
  B. replication.
  C. transcription.
  D. mutation.
    
A  
   
18. An allosteric receptor embedded in a cell membrane will change shape only

 A. when a molecule attempting to dock with the enzyme doesn't actually fit.
  B. in response to a signal from within the cell.
  C. as cellular changes demand it.
  D. when a signal molecule fits the shape of the receptor

A

Answer
Thanks for using AllExperts. I prefer not to simply answer homework questions directly, so here's what I'll do: I will tell you which answers appear to be incorrect, and leave it up to you to determine what the correct answer actually is. That process of looking up and reviewing the material will very much help you to understand this information. Science is often difficult and requires a lot of attention; I'm sure, however, that you will be able to master it at this level.

These answers should be the ones you review:

1, 2, 3, 4, 6, 9, 11, 13, 14, 16, 17, 18

Seven is a poorly-worded question, and I cannot determine what the correct answer should be. I would disregard it.

Eight is also unclear. The enzymes most similar to the description provided are helicase and topoisomerase, both of which you should look up to get an appreciation of DNA transcription.

Good luck.