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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. 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
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 model of how bacteria turn on and off genes
The different forms of a gene. Two copies may not be identical

2. 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. 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 different forms of a gene. Two copies may not be identical
Frequency

3. What does the Law of Segregation state?
The model of how bacteria turn on and off genes
Organisms that have one copy of a dominant allele and one recessive allele
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.

4. What does the Law of Independent Assortment state?
Epigenesis
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
A functional unit of gene expression made up of several related genes - an operator and promoter
Proteins that attaches to the operator sequence only when a certain compound is present in the environment

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

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

7. What is a Polygene?
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.
The different forms of a gene. Two copies may not be identical
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.
Proteins that attaches to the operator sequence only when a certain compound is present in the environment

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

9. Who is Thomas Hunt Morgan
Organisms that have one copy of a dominant allele and one recessive allele
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
Transduction - Transformation and Conjugation
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

10. Define Inducible enzymes
Enzymes that can be induced/turned on when in the presence of a particular substance
Is the type of genes an organism has
In the nucleoid region
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

11. Define Allele
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 extent to which a given gene expresses itself in an individual or population
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

12. In Bacteria - in what region of the cell is the DNA found?
In the nucleoid region
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.
Defective proteins
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.

13. What is the Operon model?
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.
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 a second gene determines whether a first gene is expressed or not.

14. Define genotype
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. You have two copies of each chromosome - one from mom and one from dad. Also - 2 copies of each gene
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
Is the type of genes an organism has

15. Describe the lac operon model
Epigenesis
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
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

16. What is Mitochondrial (maternal) Inheritance?

17. Genomic Imprinting is also known by what other name?
Is the type of genes an organism has
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
Organisms that have two copies of the same allele

18. What are characteristics of X-linked recessive traits?
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
When a second gene determines whether a first gene is expressed or not.
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

19. What is Transduction?
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 two copies of the same allele
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 extent to which a given gene expresses itself in an individual or population

20. What is a homozygous organism?
Organisms that have two copies of the same allele
A functional unit of gene expression made up of several related genes - an operator and promoter
Organisms that have one copy of a dominant allele and one recessive allele
Frequency

21. 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
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
The model of how bacteria turn on and off genes

22. 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).
Organisms that have one copy of a dominant allele and one recessive allele
Epigenesis
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

23. Define Penetrance
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.
Epigenesis
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

24. 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
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
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.

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

26. Dominant trait
Frequency
Proteins that attaches to the operator sequence only when a certain compound is present in the environment
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

27. What is an Operon?
When bacteria pick up 'naked' DNA that has spilled out of lysed bacterial cells nearby or has been placed in a surrounding environment.
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.
A functional unit of gene expression made up of several related genes - an operator and promoter

28. What is the Triplet Repeat Extension? What diseases are caused by this?
Epigenesis
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 model of how bacteria turn on and off genes

29. Describe how incomplete dominance occurs and what is it.
Defective proteins
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
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
Is the type of genes an organism has

30. When does Epistasis occur?
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
3 genes (lac Z - lac Y and lacA) - promoter region and an operator region. Function: responsible for the breakdown of lactose.
A functional unit of gene expression made up of several related genes - an operator and promoter

31. What are R-Plasmids?
A functional unit of gene expression made up of several related genes - an operator and promoter
Plasmids that contain antibiotic resistance genes - which code for enzymes that may break down or interfere with antibiotics.
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.

32. What is the process of Transformation?

33. What is Genomic Imprinting?
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
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
When bacteria pick up 'naked' DNA that has spilled out of lysed bacterial cells nearby or has been placed in a surrounding environment.
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.

34. What are characteristics of autosomal dominant traits?
The extent to which a given gene expresses itself in an individual or population
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 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
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

35. What is Conjugation?
Process that occurs between bacterial cells though cytoplasmic extensions that allow plasmids to move between cells.
When a second gene determines whether a first gene is expressed or not.
When bacteria pick up 'naked' DNA that has spilled out of lysed bacterial cells nearby or has been placed in a surrounding environment.
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.

36. What is genetic anticipation?
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 model of how bacteria turn on and off genes
The building up of a trait over the course of several generations.
The physical features of an organism

37. 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
Frequency
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

38. What are the parts of a lac operon? What is its function?
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
Is the type of genes an organism has
1. You have two copies of each chromosome - one from mom and one from dad. Also - 2 copies of each gene
3 genes (lac Z - lac Y and lacA) - promoter region and an operator region. Function: responsible for the breakdown of lactose.

39. What does it mean to be a diploid organism?
Transduction - Transformation and Conjugation
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
Frequency

40. Define Repressor Enzymes
Transduction - Transformation and Conjugation
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
Proteins that attaches to the operator sequence only when a certain compound is present in the environment
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