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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. What is genetic anticipation?
Frequency
The building up of a trait over the course of several generations.
Organisms that have one copy of a dominant allele and one recessive 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

2. What are characteristics of X-linked recessive traits?
The model of how bacteria turn on and off genes
3 genes (lac Z - lac Y and lacA) - promoter region and an operator region. Function: responsible for the breakdown of lactose.
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. 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. What does the Law of Independent Assortment state?
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 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
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.

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

5. 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.
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
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
Frequency

6. 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
When a second gene determines whether a first gene is expressed or not.
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 physical features of an organism

7. What is a homozygous 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
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
Organisms that have two copies of the same allele

8. Genomic Imprinting is also known by what other name?
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
Epigenesis
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.
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

9. 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.
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
Proteins that attaches to the operator sequence only when a certain compound is present in the environment
In the nucleoid region

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

11. Describe how incomplete dominance occurs and what is it.
The different forms of a gene. Two copies may not be identical
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.
Is the type of genes an organism has

12. Who is Thomas Hunt Morgan
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. 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
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
A functional unit of gene expression made up of several related genes - an operator and promoter

13. What is Conjugation?
The extent to which a given gene expresses itself in an individual or population
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.
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

14. What is a heterozygous organism?
Proteins that attaches to the operator sequence only when a certain compound is present in the environment
Organisms that have one copy of a dominant allele and one recessive allele
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

15. What does the Law of Segregation state?
Enzymes that can be induced/turned on when in the presence of a particular substance
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.
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.

16. What is the process of Transformation?

17. What are characteristics of autosomal dominant traits?
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
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
Organisms that have two copies of the same allele

18. What is the Operon model?
The model of how bacteria turn on and off genes
Organisms that have two copies of the same allele
Enzymes that can be induced/turned on when in the presence of a particular substance
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

19. Recessive alleles when transcribed produce ___________ that cannot preform their given function
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
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
Defective proteins

20. What are characteristics of autosomal recessive traits?
In the nucleoid region
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.
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

21. Define phenotype
The physical features of an 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.
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

22. What are R-Plasmids?
1. You have two copies of each chromosome - one from mom and one from dad. Also - 2 copies of each gene
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
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

23. Define Repressor Enzymes
Proteins that attaches to the operator sequence only when a certain compound is present in the environment
Is the type of genes an organism has
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. 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. Define Inducible enzymes
Organisms that have one copy of a dominant allele and one recessive allele
The model of how bacteria turn on and off genes
Enzymes that can be induced/turned on when in the presence of a particular substance
Epigenesis

25. What is a Polygene?
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 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.
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

26. 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
Proteins that attaches to the operator sequence only when a certain compound is present in the environment
Transduction - Transformation and Conjugation
Organisms that have one copy of a dominant allele and one recessive allele

27. Males cannot be carriers of sex linked traits
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.
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

28. Define Allele
Transduction - Transformation and Conjugation
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.
When bacteria pick up 'naked' DNA that has spilled out of lysed bacterial cells nearby or has been placed in a surrounding environment.

29. What are 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
The building up of a trait over the course of several generations.
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
Transduction - Transformation and Conjugation

30. When does Epistasis occur?
Defective proteins
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
When a second gene determines whether a first gene is expressed or not.
Enzymes that can be induced/turned on when in the presence of a particular substance

31. Dominant trait
Is the type of genes an organism has
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. 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

32. What is Mitochondrial (maternal) Inheritance?

33. When does Codominance occur?
Organisms that have one copy of a dominant allele and one recessive allele
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
Is the type of genes an organism has
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

34. Describe the lac operon model
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 model of how bacteria turn on and off genes
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.

35. What does it mean to be a diploid organism?
In the nucleoid region
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. 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

36. What is Transduction?
Organisms that have two copies of the same allele
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.
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

37. What is an Operon?
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
A functional unit of gene expression made up of several related genes - an operator and promoter
Epigenesis
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

38. 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.
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
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
Organisms that have one copy of a dominant allele and one recessive allele

39. What is Genomic Imprinting?
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.
Frequency
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
Epigenesis

40. Define genotype
Organisms that have two copies of the same allele
Frequency
Is the type of genes an organism has
3 genes (lac Z - lac Y and lacA) - promoter region and an operator region. Function: responsible for the breakdown of lactose.