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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. Define Repressor Enzymes
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.
The physical features of an organism
The different forms of a gene. Two copies may not be identical
Proteins that attaches to the operator sequence only when a certain compound is present in the environment

2. What are characteristics of autosomal dominant traits?
The model of how bacteria turn on and off genes
The extent to which a given gene expresses itself in an individual or population
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
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. Define phenotype
The physical features of an organism
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.
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 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

4. What is Genomic Imprinting?
Organisms that have two copies of the same allele
Frequency
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
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.

5. What is Mitochondrial (maternal) Inheritance?

6. What is genetic anticipation?
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. 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
The physical features of an organism
The building up of a trait over the course of several generations.

7. What are characteristics of X-linked recessive traits?
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. 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 a second gene determines whether a first gene is expressed or not.
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).

8. What 3 ways do bacteria recombine genes and shuffle their gene pools from generation to generation in the absence of sexual reproduction?
When bacteria pick up 'naked' DNA that has spilled out of lysed bacterial cells nearby or has been placed in a surrounding environment.
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
Enzymes that can be induced/turned on when in the presence of a particular substance

9. What is the Triplet Repeat Extension? What diseases are caused by this?
In the nucleoid region
Defective proteins
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. 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

10. Describe how incomplete dominance occurs and what is it.
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.
In the nucleoid region
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
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

11. What are plasmids?
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
The building up of a trait over the course of several generations.
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
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

12. 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
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
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.

13. What is an Operon?
Is the type of genes an organism has
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. 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

14. What are characteristics of autosomal recessive traits?
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
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.
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.
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

15. Define genotype
Epigenesis
Transduction - Transformation and Conjugation
Is the type of genes an organism has
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

16. What is the Operon model?
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
Enzymes that can be induced/turned on when in the presence of a particular substance
The model of how bacteria turn on and off genes
The building up of a trait over the course of several generations.

17. Dominant trait
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
3 genes (lac Z - lac Y and lacA) - promoter region and an operator region. Function: responsible for the breakdown of lactose.
Transduction - Transformation and Conjugation

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

19. Recessive alleles when transcribed produce ___________ that cannot preform their given function
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.
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.
Defective proteins
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

20. 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
The different forms of a gene. Two copies may not be identical
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 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

21. What is Transduction?
The building up of a trait over the course of several generations.
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).
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
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.

22. In Bacteria - in what region of the cell is the DNA found?
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.
Organisms that have one copy of a dominant allele and one recessive allele
Epigenesis
In the nucleoid region

23. What is Conjugation?
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.
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
Organisms that have two copies of the same allele
The building up of a trait over the course of several generations.

24. Define Allele
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
3 genes (lac Z - lac Y and lacA) - promoter region and an operator region. Function: responsible for the breakdown of lactose.
The different forms of a gene. Two copies may not be identical
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

25. What are the parts of a lac operon? What is its function?
Frequency
Epigenesis
3 genes (lac Z - lac Y and lacA) - promoter region and an operator region. Function: responsible for the breakdown of lactose.
The physical features of an organism

26. Males cannot be carriers of sex linked traits
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
In the nucleoid region
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

27. What is a homozygous organism?
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
Organisms that have two copies of the same allele
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
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).

28. What is the process of Transformation?

29. When does Codominance occur?
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
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
The physical features of an organism

30. Who is Thomas Hunt Morgan
The building up of a trait over the course of several generations.
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.
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 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

31. Define Inducible enzymes
Transduction - Transformation and Conjugation
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
The different forms of a gene. Two copies may not be identical
Enzymes that can be induced/turned on when in the presence of a particular substance

32. What is a heterozygous organism?
Organisms that have one copy of a dominant allele and one recessive allele
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.
Defective proteins
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.

33. Genomic Imprinting is also known by what other name?
Epigenesis
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.
The model of how bacteria turn on and off genes
Transduction - Transformation and Conjugation

34. 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.
Organisms that have two copies of the same allele
Epigenesis
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

35. What does it mean to be a diploid organism?
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).
Frequency
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

36. What are R-Plasmids?
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.
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
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.
3 genes (lac Z - lac Y and lacA) - promoter region and an operator region. Function: responsible for the breakdown of lactose.

37. Define Penetrance
The extent to which a given gene expresses itself in an individual or population
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
Proteins that attaches to the operator sequence only when a certain compound is present in the environment
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

38. Describe the lac operon model
Defective proteins
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
The different forms of a gene. Two copies may not be identical

39. When does Epistasis occur?
Organisms that have two copies of the same allele
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.
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

40. What does the Law of Segregation state?
Is the type of genes an organism has
The extent to which a given gene expresses itself in an individual or population
3 genes (lac Z - lac Y and lacA) - promoter region and an operator region. Function: responsible for the breakdown of lactose.
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