Many genes in the human genome are no longer expressed because mutations have introduced stop codons within the coding sequence or transposons have disrupted gene function. These genes are now considered

Question

A.  pseudogenes.
B.  orthologs.
C.  paralogs.
D.  homologues.

Clarify Question
  · What is the key concept addressed by the question?
· What type of thinking is required?
· What key words does the question contain and what do they mean?
 
Gather Content
· What do you already know about pseudogenes?
 
Consider Possibilities
· Consider the different answer options. Which can you rule out?

  Choose Answer
· Given what you now know, what information and/or problem solving approach is most likely to produce the correct answer?
 
Reflect on Process
· Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?

Answer 1

A.  pseudogenes.

Clarify Question
  · What is the key concept addressed by the question?
        o This question addresses pseudogenes.
· What type of thinking is required?
        o This question is asking you to take what you already know and apply it to this unfamiliar situation.
· What key words does the question contain and what do they mean?
        o If a gene is no longer expressed, that means it is not transcribed and translated into protein.
        o Transposons are small pieces of DNA that can hop into new locations.
 
Gather Content
· What do you already know about pseudogenes?
        o Pseudogenes are inactive.
        o They do not produce a functional product due to premature stop codons, missense mutations, or deletions.
 
Consider Possibilities
· Consider the different answer options. Which can you rule out?
        o Do we call inactive genes homologues, orthologs, or paralogs? No. These are all terms that describe the evolutionary relationship between a pair of genes. They do not indicate whether a gene is functional or not.

  Choose Answer
· Given what you now know, what information and/or problem solving approach is most likely to produce the correct answer?
        o Is an inactive gene a pseudogene? Yes, that is the correct term for an inactive gene that remains in the genome.
 
Reflect on Process
· Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
        o This question asked what term describes genes that have become nonfunctional due to mutations.
        o The question required you to take what you already know and apply it to this unfamiliar situation.
        o Did you remember that nonfunctional or nonexpressed genes in the genome are called pseudogenes?