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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 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
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
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
Frequency

2. 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
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.
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.
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. What are characteristics of X-linked 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. 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 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
3 genes (lac Z - lac Y and lacA) - promoter region and an operator region. Function: responsible for the breakdown of lactose.

4. What is Conjugation?
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.
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 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.
A functional unit of gene expression made up of several related genes - an operator and promoter

5. What is Transduction?
1. You have two copies of each chromosome - one from mom and one from dad. Also - 2 copies of each gene
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.
Organisms that have one copy of a dominant allele and one recessive 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

6. What is a homozygous organism?
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
In the nucleoid region
The physical features of an organism
Organisms that have two copies of the same allele

7. Describe how incomplete dominance occurs and what is it.
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 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).
Organisms that have one copy of a dominant allele and one recessive allele

8. Who is Thomas Hunt Morgan
The different forms of a gene. Two copies may not be identical
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
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
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

9. What is Genomic Imprinting?
The physical features of an organism
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
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.

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

11. What is the process of Transformation?

12. Define phenotype
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 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
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

13. 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
In the nucleoid region
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 different forms of a gene. Two copies may not be identical

14. 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
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.
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

15. Define Repressor Enzymes
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 bacteria pick up 'naked' DNA that has spilled out of lysed bacterial cells nearby or has been placed in a surrounding environment.
Proteins that attaches to the operator sequence only when a certain compound is present in the environment
Epigenesis

16. Describe the lac operon model
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
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
In the nucleoid region

17. What is an Operon?
A functional unit of gene expression made up of several related genes - an operator and promoter
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 extent to which a given gene expresses itself in an individual or population
1. You have two copies of each chromosome - one from mom and one from dad. Also - 2 copies of each gene

18. Define genotype
Is the type of genes an organism has
The physical features of an organism
In the nucleoid region
A functional unit of gene expression made up of several related genes - an operator and promoter

19. Dominant trait
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 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
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.

20. What does the Law of Independent Assortment state?
The model of how bacteria turn on and off genes
When a second gene determines whether a first gene is expressed or not.
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
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

21. What is Mitochondrial (maternal) Inheritance?

22. In Bacteria - in what region of the cell is the DNA found?
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
In the nucleoid region
The different forms of a gene. Two copies may not be identical
Organisms that have one copy of a dominant allele and one recessive allele

23. Define Inducible enzymes
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
3 genes (lac Z - lac Y and lacA) - promoter region and an operator region. Function: responsible for the breakdown of lactose.
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

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

25. What is genetic anticipation?
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.
Frequency
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

26. 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
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 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.

27. 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 building up of a trait over the course of several generations.
Organisms that have two copies of the same allele

28. What are characteristics of autosomal dominant 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. 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. 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
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

29. What are R-Plasmids?
Enzymes that can be induced/turned on when in the presence of a particular substance
The extent to which a given gene expresses itself in an individual or population
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).
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.

30. When does Epistasis occur?
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
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 a second gene determines whether a first gene is expressed or not.
The different forms of a gene. Two copies may not be identical

31. Males cannot be carriers of sex linked traits
Proteins that attaches to the operator sequence only when a certain compound is present in the environment
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 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 bacteria pick up 'naked' DNA that has spilled out of lysed bacterial cells nearby or has been placed in a surrounding environment.

32. What are plasmids?
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
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
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
Defective proteins

33. What are characteristics of autosomal recessive traits?
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
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
3 genes (lac Z - lac Y and lacA) - promoter region and an operator region. Function: responsible for the breakdown of lactose.

34. Recessive alleles when transcribed produce ___________ that cannot preform their given function
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.
Is the type of genes an organism has
Defective proteins
Proteins that attaches to the operator sequence only when a certain compound is present in the environment

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

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

37. Genomic Imprinting is also known by what other name?
Transduction - Transformation and Conjugation
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
Epigenesis

38. What is a heterozygous 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
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.
3 genes (lac Z - lac Y and lacA) - promoter region and an operator region. Function: responsible for the breakdown of lactose.
Organisms that have one copy of a dominant allele and one recessive allele

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

40. What is the Triplet Repeat Extension? What diseases are caused by this?
The physical features of an organism
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
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