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GRE Molecular Biology

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Answer 40 questions in 15 minutes.
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Match each statement with the correct term.
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1. When does Codominance occur?
This is a genetic inheritance pattern that results from the fact that certain alleles seem to be encoded differently depending upon which parent the allele comes from.
When the different alleles for a trait each code for enough protein so that - when they occur together - two different - normal proteins are made and show up in the organisms phenotype. For examples - blood types Ia - Ib - and Ia and Ib will be codom
A functional unit of gene expression made up of several related genes - an operator and promoter
Is the type of genes an organism has

2. Males cannot be carriers of sex linked traits
RNA polymerase attaches to promoter sequence immediately prior to the gene that is to be transcribed - follows along the DNA strand - reading DNA into mRNA ? repressor protein (controlled by a regulatory gene) binds to operator not allowing RNA to mo
Males only have one X chromosomes in addition to their Y chromosome. If this X has the mutant gene on it - there is no normal gene to override. Female have a chance of having a normal gene on the other X that can produce enough normal protein that th
Defective proteins
The physical features of an organism

3. What is genetic anticipation?
The building up of a trait over the course of several generations.
The degree to which one expresses a trait depends upon the ratio of dominant to recessive alleles in that group of gene. Is responsible - for example - the variations in skin color.
Proteins that attaches to the operator sequence only when a certain compound is present in the environment
RNA polymerase attaches to promoter sequence immediately prior to the gene that is to be transcribed - follows along the DNA strand - reading DNA into mRNA ? repressor protein (controlled by a regulatory gene) binds to operator not allowing RNA to mo

4. What is the Triplet Repeat Extension? What diseases are caused by this?
1. When some genes normally contain terminal regions of C-A-G nucleotide repeats or other repeats that can extend up to 50 repeats long in normal - healthy individuals. 2. Huntingtons disease and the Fragile X Syndrome
Males only have one X chromosomes in addition to their Y chromosome. If this X has the mutant gene on it - there is no normal gene to override. Female have a chance of having a normal gene on the other X that can produce enough normal protein that th
The extent to which a given gene expresses itself in an individual or population
When a second gene determines whether a first gene is expressed or not.

5. What are R-Plasmids?
Small loops of dsDNA that exist within bacterial cells - but not as a part of the single - large chromosome.They replicate independently of the larger chromosome and can be freely exchanged from bacterial cell to bacterial cell via extensions of cyto
Organisms that have two copies of the same allele
RNA polymerase attaches to promoter sequence immediately prior to the gene that is to be transcribed - follows along the DNA strand - reading DNA into mRNA ? repressor protein (controlled by a regulatory gene) binds to operator not allowing RNA to mo
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.

6. Dominance has nothing to do with __________. Dominant alleles are not more common in populations than recessive alleles. Dominance is not an allele that overpowers a recessive allele.
When a second gene determines whether a first gene is expressed or not.
Frequency
Males only have one X chromosomes in addition to their Y chromosome. If this X has the mutant gene on it - there is no normal gene to override. Female have a chance of having a normal gene on the other X that can produce enough normal protein that th
Proteins that attaches to the operator sequence only when a certain compound is present in the environment

7. What is an Operon?
The physical features of an organism
When bacteria pick up 'naked' DNA that has spilled out of lysed bacterial cells nearby or has been placed in a surrounding environment.
A functional unit of gene expression made up of several related genes - an operator and promoter
Transduction - Transformation and Conjugation

8. Define Penetrance
The extent to which a given gene expresses itself in an individual or population
Males only have one X chromosomes in addition to their Y chromosome. If this X has the mutant gene on it - there is no normal gene to override. Female have a chance of having a normal gene on the other X that can produce enough normal protein that th
That genes for one trait separate independent of genes for other traits. So - the variation of the different combinations you could get between Ww and Yy. Can find this out by doing a hybrid cross
The model of how bacteria turn on and off genes

9. Define Inducible enzymes
Organisms that have one copy of a dominant allele and one recessive allele
1. All daughters of a male who has the trait will also have the trait 2. There is no male-to-male transmission 3. A female who has the trait may or may not pass on the affected X to her son or daughter (unless she has two affected X'S).
Enzymes that can be induced/turned on when in the presence of a particular substance
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.

10. What are plasmids?
Defective proteins
The extent to which a given gene expresses itself in an individual or population
Small loops of dsDNA that exist within bacterial cells - but not as a part of the single - large chromosome.They replicate independently of the larger chromosome and can be freely exchanged from bacterial cell to bacterial cell via extensions of cyto
Means that a trait is expressed even if there is only one copy of the allele. Both sex linked and autosomal traits will be expressed if coded for by a dominant gene - regardless of the other copy of the gene on the homologous chromosome

11. Define phenotype
Organisms that have one copy of a dominant allele and one recessive allele
Small loops of dsDNA that exist within bacterial cells - but not as a part of the single - large chromosome.They replicate independently of the larger chromosome and can be freely exchanged from bacterial cell to bacterial cell via extensions of cyto
Males only have one X chromosomes in addition to their Y chromosome. If this X has the mutant gene on it - there is no normal gene to override. Female have a chance of having a normal gene on the other X that can produce enough normal protein that th
The physical features of an organism

12. What does it mean to be a diploid organism?
The different forms of a gene. Two copies may not be identical
This is a genetic inheritance pattern that results from the fact that certain alleles seem to be encoded differently depending upon which parent the allele comes from.
1. You have two copies of each chromosome - one from mom and one from dad. Also - 2 copies of each gene
Transduction - Transformation and Conjugation

13. Define Allele
The different forms of a gene. Two copies may not be identical
1. Males and females are equally likely to have the trait 2. Traits often skip generations 3. only homozygous individuals have the trait 4. Traits can appear in siblings without appearing in parents 5. If a parent has the trait - those offspring who
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.
When a second gene determines whether a first gene is expressed or not.

14. What are the parts of a lac operon? What is its function?
1. You have two copies of each chromosome - one from mom and one from dad. Also - 2 copies of each gene
When the different alleles for a trait each code for enough protein so that - when they occur together - two different - normal proteins are made and show up in the organisms phenotype. For examples - blood types Ia - Ib - and Ia and Ib will be codom
3 genes (lac Z - lac Y and lacA) - promoter region and an operator region. Function: responsible for the breakdown of lactose.
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.

15. What are characteristics of autosomal dominant traits?
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.
RNA polymerase attaches to promoter sequence immediately prior to the gene that is to be transcribed - follows along the DNA strand - reading DNA into mRNA ? repressor protein (controlled by a regulatory gene) binds to operator not allowing RNA to mo
Small loops of dsDNA that exist within bacterial cells - but not as a part of the single - large chromosome.They replicate independently of the larger chromosome and can be freely exchanged from bacterial cell to bacterial cell via extensions of cyto
1. Males and females are equally likely to have the trait 2. Traits do not skip generations 3. The trait is present if the corresponding gene is present 4. there is male to male and female - to - female transmission

16. What is the process of Transformation?

17. Genomic Imprinting is also known by what other name?
This is a genetic inheritance pattern that results from the fact that certain alleles seem to be encoded differently depending upon which parent the allele comes from.
Epigenesis
1. Males and females are equally likely to have the trait 2. Traits often skip generations 3. only homozygous individuals have the trait 4. Traits can appear in siblings without appearing in parents 5. If a parent has the trait - those offspring who
Organisms that have one copy of a dominant allele and one recessive allele

18. Describe the lac operon model
When one'S cellular organelles derive entirely from the mother - all genes present in one'S organelles have a maternal - rather than paternal origin. Sperm contains no organelles that are transferred to the egg upon fertilization
RNA polymerase attaches to promoter sequence immediately prior to the gene that is to be transcribed - follows along the DNA strand - reading DNA into mRNA ? repressor protein (controlled by a regulatory gene) binds to operator not allowing RNA to mo
1. You have two copies of each chromosome - one from mom and one from dad. Also - 2 copies of each gene
1. When some genes normally contain terminal regions of C-A-G nucleotide repeats or other repeats that can extend up to 50 repeats long in normal - healthy individuals. 2. Huntingtons disease and the Fragile X Syndrome

19. What is Conjugation?
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.
Small loops of dsDNA that exist within bacterial cells - but not as a part of the single - large chromosome.They replicate independently of the larger chromosome and can be freely exchanged from bacterial cell to bacterial cell via extensions of cyto
1. You have two copies of each chromosome - one from mom and one from dad. Also - 2 copies of each gene
When a second gene determines whether a first gene is expressed or not.

20. What 3 ways do bacteria recombine genes and shuffle their gene pools from generation to generation in the absence of sexual reproduction?
The physical features of an organism
Organisms that have two copies of the same allele
RNA polymerase attaches to promoter sequence immediately prior to the gene that is to be transcribed - follows along the DNA strand - reading DNA into mRNA ? repressor protein (controlled by a regulatory gene) binds to operator not allowing RNA to mo
Transduction - Transformation and Conjugation

21. What does the Law of Independent Assortment state?
1. You have two copies of each chromosome - one from mom and one from dad. Also - 2 copies of each gene
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.
Males only have one X chromosomes in addition to their Y chromosome. If this X has the mutant gene on it - there is no normal gene to override. Female have a chance of having a normal gene on the other X that can produce enough normal protein that th
That genes for one trait separate independent of genes for other traits. So - the variation of the different combinations you could get between Ww and Yy. Can find this out by doing a hybrid cross

22. What is a Polygene?
The degree to which one expresses a trait depends upon the ratio of dominant to recessive alleles in that group of gene. Is responsible - for example - the variations in skin color.
1. You have two copies of each chromosome - one from mom and one from dad. Also - 2 copies of each gene
The model of how bacteria turn on and off genes
In the nucleoid region

23. What is a homozygous organism?
Organisms that have two copies of the same allele
Transduction - Transformation and Conjugation
1. You have two copies of each chromosome - one from mom and one from dad. Also - 2 copies of each gene
1. Males and females are equally likely to have the trait 2. Traits often skip generations 3. only homozygous individuals have the trait 4. Traits can appear in siblings without appearing in parents 5. If a parent has the trait - those offspring who

24. What is Mitochondrial (maternal) Inheritance?

25. Define Repressor Enzymes
1. You have two copies of each chromosome - one from mom and one from dad. Also - 2 copies of each gene
In the nucleoid region
1. Males and females are equally likely to have the trait 2. Traits do not skip generations 3. The trait is present if the corresponding gene is present 4. there is male to male and female - to - female transmission
Proteins that attaches to the operator sequence only when a certain compound is present in the environment

26. What does the Law of Segregation state?
1. Males and females are equally likely to have the trait 2. Traits often skip generations 3. only homozygous individuals have the trait 4. Traits can appear in siblings without appearing in parents 5. If a parent has the trait - those offspring who
That two alleles for a given trait separate from each other during meiosis - and thus - end up in different sperm or egg cells. So an organism can pass on a W or a w from a set of Ww - but never both
When one'S cellular organelles derive entirely from the mother - all genes present in one'S organelles have a maternal - rather than paternal origin. Sperm contains no organelles that are transferred to the egg upon fertilization
Epigenesis

27. Describe how incomplete dominance occurs and what is it.
When the different alleles for a trait each code for enough protein so that - when they occur together - two different - normal proteins are made and show up in the organisms phenotype. For examples - blood types Ia - Ib - and Ia and Ib will be codom
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.
1. Incomplete dominance occurs when the dominant allele does not code for enough of a given protein. You see the full effect of the gene when two copies of the dominant allele are present in the cell. Like with flowers - 2 red alleles are red - 2 whi
Enzymes that can be induced/turned on when in the presence of a particular substance

28. What are characteristics of autosomal recessive traits?
1. Trait is far more common in males than in females 2. All daughters of a male who has the trait are heterozygous carriers 3. There is no male-to-male transmission 4. Mothers of males who have the trait are either heterozygous carriers or homozygous
1. Males and females are equally likely to have the trait 2. Traits often skip generations 3. only homozygous individuals have the trait 4. Traits can appear in siblings without appearing in parents 5. If a parent has the trait - those offspring who
A functional unit of gene expression made up of several related genes - an operator and promoter
Epigenesis

29. When does Epistasis occur?
Enzymes that can be induced/turned on when in the presence of a particular substance
When a second gene determines whether a first gene is expressed or not.
The degree to which one expresses a trait depends upon the ratio of dominant to recessive alleles in that group of gene. Is responsible - for example - the variations in skin color.
1. Incomplete dominance occurs when the dominant allele does not code for enough of a given protein. You see the full effect of the gene when two copies of the dominant allele are present in the cell. Like with flowers - 2 red alleles are red - 2 whi

30. Define genotype
1. Trait is far more common in males than in females 2. All daughters of a male who has the trait are heterozygous carriers 3. There is no male-to-male transmission 4. Mothers of males who have the trait are either heterozygous carriers or homozygous
When bacteria pick up 'naked' DNA that has spilled out of lysed bacterial cells nearby or has been placed in a surrounding environment.
Is the type of genes an organism has
When a second gene determines whether a first gene is expressed or not.

31. What is the Operon model?
Organisms that have one copy of a dominant allele and one recessive allele
Is the type of genes an organism has
The model of how bacteria turn on and off genes
Proteins that attaches to the operator sequence only when a certain compound is present in the environment

32. What are characteristics of X-linked recessive traits?
Is the type of genes an organism has
Proteins that attaches to the operator sequence only when a certain compound is present in the environment
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.
1. Trait is far more common in males than in females 2. All daughters of a male who has the trait are heterozygous carriers 3. There is no male-to-male transmission 4. Mothers of males who have the trait are either heterozygous carriers or homozygous

33. Who is Thomas Hunt Morgan
The degree to which one expresses a trait depends upon the ratio of dominant to recessive alleles in that group of gene. Is responsible - for example - the variations in skin color.
Rediscovered mendels work to help figure out why traits were passed on in the patterns that he saw. Helped to discover the concept of gene linkage
That two alleles for a given trait separate from each other during meiosis - and thus - end up in different sperm or egg cells. So an organism can pass on a W or a w from a set of Ww - but never both
In the nucleoid region

34. Dominant trait
Proteins that attaches to the operator sequence only when a certain compound is present in the environment
Frequency
Small loops of dsDNA that exist within bacterial cells - but not as a part of the single - large chromosome.They replicate independently of the larger chromosome and can be freely exchanged from bacterial cell to bacterial cell via extensions of cyto
Means that a trait is expressed even if there is only one copy of the allele. Both sex linked and autosomal traits will be expressed if coded for by a dominant gene - regardless of the other copy of the gene on the homologous chromosome

35. What is a heterozygous organism?
Organisms that have one copy of a dominant allele and one recessive allele
The building up of a trait over the course of several generations.
Rediscovered mendels work to help figure out why traits were passed on in the patterns that he saw. Helped to discover the concept of gene linkage
When one'S cellular organelles derive entirely from the mother - all genes present in one'S organelles have a maternal - rather than paternal origin. Sperm contains no organelles that are transferred to the egg upon fertilization

36. In Bacteria - in what region of the cell is the DNA found?
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.
A functional unit of gene expression made up of several related genes - an operator and promoter
In the nucleoid region
Rediscovered mendels work to help figure out why traits were passed on in the patterns that he saw. Helped to discover the concept of gene linkage

37. What are characteristics of X-Linked dominant traits?

38. What is Transduction?
The process by which viruses infect certain bacterial cells - allowing new baby viruses to trap bacterial genes. Can transfer DNA to new cells - which can integrate into the host cells chromosomes.
Means that a trait is expressed even if there is only one copy of the allele. Both sex linked and autosomal traits will be expressed if coded for by a dominant gene - regardless of the other copy of the gene on the homologous chromosome
The different forms of a gene. Two copies may not be identical
When bacteria pick up 'naked' DNA that has spilled out of lysed bacterial cells nearby or has been placed in a surrounding environment.

39. What is Genomic Imprinting?
The extent to which a given gene expresses itself in an individual or population
This is a genetic inheritance pattern that results from the fact that certain alleles seem to be encoded differently depending upon which parent the allele comes from.
That genes for one trait separate independent of genes for other traits. So - the variation of the different combinations you could get between Ww and Yy. Can find this out by doing a hybrid cross
When a second gene determines whether a first gene is expressed or not.

40. Recessive alleles when transcribed produce ___________ that cannot preform their given function
That genes for one trait separate independent of genes for other traits. So - the variation of the different combinations you could get between Ww and Yy. Can find this out by doing a hybrid cross
A functional unit of gene expression made up of several related genes - an operator and promoter
1. Incomplete dominance occurs when the dominant allele does not code for enough of a given protein. You see the full effect of the gene when two copies of the dominant allele are present in the cell. Like with flowers - 2 red alleles are red - 2 whi
Defective proteins