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GRE Molecular Biology

Instructions:

Answer 40 questions in 15 minutes.
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Match each statement with the correct term.
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1. What is the Triplet Repeat Extension? What diseases are caused by this?
The model of how bacteria turn on and off genes
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
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.

2. What are the parts of a lac operon? What is its function?
3 genes (lac Z - lac Y and lacA) - promoter region and an operator region. Function: responsible for the breakdown of lactose.
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
Is the type of genes an organism has
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

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

4. When does Epistasis occur?
The different forms of a gene. Two copies may not be identical
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.
The building up of a trait over the course of several generations.
When a second gene determines whether a first gene is expressed or not.

5. Genomic Imprinting is also known by what other name?
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. 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
The extent to which a given gene expresses itself in an individual or population
Epigenesis

6. Males cannot be carriers of sex linked traits
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
Epigenesis
The physical features of an organism

7. Recessive alleles when transcribed produce ___________ that cannot preform their given function
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.
Defective proteins
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
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

8. 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.
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
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.
The physical features of an organism

9. What is Transduction?
Epigenesis
1. You have two copies of each chromosome - one from mom and one from dad. Also - 2 copies of each gene
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 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.

10. Describe the lac operon model
When a second gene determines whether a first gene is expressed or not.
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
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
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

11. Define Inducible enzymes
Transduction - Transformation and Conjugation
Enzymes that can be induced/turned on when in the presence of a particular substance
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
Proteins that attaches to the operator sequence only when a certain compound is present in the environment

12. What is the Operon model?
The model of how bacteria turn on and off genes
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.
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
Is the type of genes an organism has

13. Describe how incomplete dominance occurs and what is it.
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
The physical features of an organism
The model of how bacteria turn on and off genes
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

14. Define Allele
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 different forms of a gene. Two copies may not be identical
Epigenesis
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

15. When does Codominance occur?
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.
Transduction - Transformation and Conjugation
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
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

16. What is a homozygous organism?
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.
Organisms that have two copies of the same allele
3 genes (lac Z - lac Y and lacA) - promoter region and an operator region. Function: responsible for the breakdown of lactose.
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

17. What does the Law of Independent Assortment state?
In the nucleoid region
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
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

18. Define Penetrance
Frequency
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).
The building up of a trait over the course of several generations.
The extent to which a given gene expresses itself in an individual or population

19. What is genetic anticipation?
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).
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.
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 building up of a trait over the course of several generations.

20. Define genotype
Is the type of genes an organism has
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
Defective proteins

21. What is an Operon?
When a second gene determines whether a first gene is expressed or not.
A functional unit of gene expression made up of several related genes - an operator and promoter
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
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

22. What is a heterozygous organism?
In the nucleoid region
Frequency
Organisms that have one copy of a dominant allele and one recessive allele
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

23. What are characteristics of X-linked recessive traits?
Is the type of genes an organism has
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. 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
3 genes (lac Z - lac Y and lacA) - promoter region and an operator region. Function: responsible for the breakdown of lactose.

24. Define phenotype
The physical features of an organism
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
Epigenesis

25. What is Genomic Imprinting?
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
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.
The extent to which a given gene expresses itself in an individual or population

26. Who is Thomas Hunt Morgan
The physical features of an organism
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
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.

27. What does the Law of Segregation state?
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
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.
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.
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

28. 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.
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.
In the nucleoid region
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.

29. What are R-Plasmids?
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.
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
Is the type of genes an organism has

30. What are characteristics of autosomal dominant 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
Organisms that have one copy of a dominant allele and one recessive allele
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

31. What is Mitochondrial (maternal) Inheritance?

32. What 3 ways do bacteria recombine genes and shuffle their gene pools from generation to generation in the absence of sexual reproduction?
Transduction - Transformation and Conjugation
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
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.

33. What are plasmids?
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
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
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 one copy of a dominant allele and one recessive allele

34. What is the process of Transformation?

35. What is Conjugation?
3 genes (lac Z - lac Y and lacA) - promoter region and an operator region. Function: responsible for the breakdown of lactose.
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.
Transduction - Transformation and Conjugation
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

36. What are characteristics of autosomal recessive traits?
A functional unit of gene expression made up of several related genes - an operator and promoter
Defective proteins
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. 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

37. Define Repressor Enzymes
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.
The building up of a trait over the course of several generations.
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

38. What is a Polygene?
Epigenesis
Enzymes that can be induced/turned on when in the presence of a particular substance
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

39. 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
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.
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).

40. What does it mean to be a diploid organism?
1. You have two copies of each chromosome - one from mom and one from dad. Also - 2 copies of each gene
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.
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
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.