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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 does it mean to be a diploid organism?
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.
Enzymes that can be induced/turned on when in the presence of a particular substance
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

2. Who is Thomas Hunt Morgan
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
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.
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
Transduction - Transformation and Conjugation

3. What is the process of Transformation?

4. What is Mitochondrial (maternal) Inheritance?

5. Define Penetrance
The extent to which a given gene expresses itself in an individual or population
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.
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).

6. What is a Polygene?
A functional unit of gene expression made up of several related genes - an operator and promoter
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
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.
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

7. Define phenotype
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
Is the type of genes an organism has
Organisms that have one copy of a dominant allele and one recessive allele
The physical features of an organism

8. Define genotype
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. 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
Proteins that attaches to the operator sequence only when a certain compound is present in the environment

9. Define Inducible enzymes
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
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
Enzymes that can be induced/turned on when in the presence of a particular substance

10. What 3 ways do bacteria recombine genes and shuffle their gene pools from generation to generation in the absence of sexual reproduction?
The extent to which a given gene expresses itself in an individual or population
Transduction - Transformation and Conjugation
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.
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

11. What are characteristics of autosomal recessive traits?
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
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 a second gene determines whether a first gene is expressed or not.

12. What is Genomic Imprinting?
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
When a second gene determines whether a first gene is expressed or not.
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 model of how bacteria turn on and off genes

13. Define Allele
The different forms of a gene. Two copies may not be identical
When a second gene determines whether a first gene is expressed or not.
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
Proteins that attaches to the operator sequence only when a certain compound is present in the environment

14. What is Conjugation?
Epigenesis
The model of how bacteria turn on and off genes
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.
The extent to which a given gene expresses itself in an individual or population

15. What is a homozygous organism?
Organisms that have one copy of a dominant allele and one recessive allele
Proteins that attaches to the operator sequence only when a certain compound is present in the environment
Frequency
Organisms that have two copies of the same allele

16. 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
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
A functional unit of gene expression made up of several related genes - an operator and promoter
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

17. What are R-Plasmids?
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.
Enzymes that can be induced/turned on when in the presence of a particular substance
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

18. Define Repressor Enzymes
Frequency
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.
Proteins that attaches to the operator sequence only when a certain compound is present in the environment

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

20. Dominant trait
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
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
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.

21. In Bacteria - in what region of the cell is the DNA found?
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
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.
In the nucleoid region
When a second gene determines whether a first gene is expressed or not.

22. What is the Operon model?
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
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 model of how bacteria turn on and off genes

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

24. Describe the lac operon model
Transduction - Transformation and Conjugation
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
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. 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.
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
Frequency
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.
Enzymes that can be induced/turned on when in the presence of a particular substance

26. Describe how incomplete dominance occurs and what is it.
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
The different forms of a gene. Two copies may not be identical
Organisms that have two copies of the same 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

27. Recessive alleles when transcribed produce ___________ that cannot preform their given function
The model of how bacteria turn on and off genes
Defective proteins
Organisms that have one copy of a dominant allele and one recessive 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

28. When does Codominance occur?
The extent to which a given gene expresses itself in an individual or population
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 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

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 physical features of an organism
1. You have two copies of each chromosome - one from mom and one from dad. Also - 2 copies of each gene

30. What does the Law of Independent Assortment state?
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. 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).
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
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

31. 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
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 a second gene determines whether a first gene is expressed or not.
Is the type of genes an organism has

32. Genomic Imprinting is also known by what other name?
Epigenesis
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
The building up of a trait over the course of several generations.

33. 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.
The extent to which a given gene expresses itself in an individual or population
Transduction - Transformation and Conjugation
Proteins that attaches to the operator sequence only when a certain compound is present in the environment

34. 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.
In the nucleoid region
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 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.

35. What are characteristics of X-linked recessive traits?
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. 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
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
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

36. What are characteristics of autosomal dominant traits?
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
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

37. What is an Operon?
A functional unit of gene expression made up of several related genes - an operator and promoter
Transduction - Transformation and Conjugation
The extent to which a given gene expresses itself in an individual or population
In the nucleoid region

38. What is the Triplet Repeat Extension? What diseases are caused by this?
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.
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.
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
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

39. What does the Law of Segregation state?
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
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
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

40. What is a heterozygous organism?
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
Organisms that have one copy of a dominant allele and one recessive 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
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).