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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 process of Transformation?

2. 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
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
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
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

3. Define genotype
Defective proteins
Is the type of genes an organism has
When bacteria pick up 'naked' DNA that has spilled out of lysed bacterial cells nearby or has been placed in a surrounding environment.
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

4. Recessive alleles when transcribed produce ___________ that cannot preform their given function
Transduction - Transformation and Conjugation
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.
Defective proteins
1. You have two copies of each chromosome - one from mom and one from dad. Also - 2 copies of each gene

5. What is the Operon model?
Defective proteins
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 model of how bacteria turn on and off genes

6. Define phenotype
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 physical features of an organism
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.
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

7. What are plasmids?
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
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.
Defective proteins
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

8. What is a Polygene?
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 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.
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

9. Define Allele
Organisms that have two copies of the same allele
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
When bacteria pick up 'naked' DNA that has spilled out of lysed bacterial cells nearby or has been placed in a surrounding environment.

10. What are characteristics of X-linked recessive traits?
Proteins that attaches to the operator sequence only when a certain compound is present in the environment
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.
Is the type of genes an organism has

11. What are the parts of a lac operon? What is its function?
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
A functional unit of gene expression made up of several related genes - an operator and promoter
3 genes (lac Z - lac Y and lacA) - promoter region and an operator region. Function: responsible for the breakdown of lactose.

12. What is Transduction?
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.
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

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

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

15. What is an Operon?
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
A functional unit of gene expression made up of several related genes - an operator and promoter
Enzymes that can be induced/turned on when in the presence of a particular substance

16. What is Mitochondrial (maternal) Inheritance?

17. What is a homozygous organism?
When bacteria pick up 'naked' DNA that has spilled out of lysed bacterial cells nearby or has been placed in a surrounding environment.
Organisms that have two copies of the same allele
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

18. 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. 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 two copies of the same allele
Transduction - Transformation and Conjugation

19. Describe the lac operon model
1. You have two copies of each chromosome - one from mom and one from dad. Also - 2 copies of each gene
Frequency
The building up of a trait over the course of several generations.
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

20. Males cannot be carriers of sex linked traits
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.
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

21. 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
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
3 genes (lac Z - lac Y and lacA) - promoter region and an operator region. Function: responsible for the breakdown of lactose.

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

23. What is a heterozygous organism?
Organisms that have two copies of the same allele
Is the type of genes an organism has
The physical features of an organism
Organisms that have one copy of a dominant allele and one recessive allele

24. When does Codominance occur?
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. 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
A functional unit of gene expression made up of several related genes - an operator and promoter
The physical features of an organism

25. What are characteristics of autosomal recessive traits?
The model of how bacteria turn on and off genes
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
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

26. Genomic Imprinting is also known by what other name?
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
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
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

27. Who is Thomas Hunt Morgan
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
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
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.

28. 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
Defective proteins
Organisms that have two copies of the same allele
Epigenesis

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

30. What is genetic anticipation?
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.
Proteins that attaches to the operator sequence only when a certain compound is present in the environment
The building up of a trait over the course of several generations.

31. 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.
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
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

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

33. What does the Law of Independent Assortment state?
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
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
Organisms that have one copy of a dominant allele and one recessive allele

34. What are R-Plasmids?
The building up of a trait over the course of several generations.
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.
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
Proteins that attaches to the operator sequence only when a certain compound is present in the environment

35. What is Genomic Imprinting?
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
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.

36. When does Epistasis occur?
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.
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 a second gene determines whether a first gene is expressed or not.
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

37. 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
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
In the nucleoid region

38. What are characteristics of autosomal dominant traits?
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
Enzymes that can be induced/turned on when in the presence of a particular substance
Organisms that have one copy of a dominant allele and one recessive allele

39. Define Penetrance
Is the type of genes an organism has
The extent to which a given gene expresses itself in an individual or population
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

40. What is Conjugation?
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.
When bacteria pick up 'naked' DNA that has spilled out of lysed bacterial cells nearby or has been placed in a surrounding environment.
Is the type of genes an organism has
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