Podcast
Questions and Answers
During which cellular process are chromosomes replicated to facilitate the creation of additional cells?
During which cellular process are chromosomes replicated to facilitate the creation of additional cells?
- Translation
- Transcription
- Mitosis (correct)
- Meiosis
Following DNA replication and condensation, a mitotic chromosome consists of what?
Following DNA replication and condensation, a mitotic chromosome consists of what?
- A single DNA strand attached to a centromere.
- A fragmented set of DNA pieces.
- Two identical sister chromatids joined at the centromere. (correct)
- Multiple homologous chromosomes intertwined at the chiasmata.
According to the central dogma of molecular biology, what is the correct order of information flow in most biological systems?
According to the central dogma of molecular biology, what is the correct order of information flow in most biological systems?
- RNA → DNA → Protein
- Protein → RNA → DNA
- DNA → RNA → Protein (correct)
- Protein → DNA → RNA
What is the primary function of mRNA in the context of the central dogma?
What is the primary function of mRNA in the context of the central dogma?
Which of the following processes represents an exception to the central dogma of molecular biology, as observed in certain viruses?
Which of the following processes represents an exception to the central dogma of molecular biology, as observed in certain viruses?
What genetic anomaly is most likely detected using karyotyping?
What genetic anomaly is most likely detected using karyotyping?
Which of the following mutations results in a shift in the reading frame during translation, provided the change does not involve a multiple of three nucleotides?
Which of the following mutations results in a shift in the reading frame during translation, provided the change does not involve a multiple of three nucleotides?
In Mendel's model of heredity, what determines the traits exhibited by an individual?
In Mendel's model of heredity, what determines the traits exhibited by an individual?
A researcher identifies a mutation where a segment of DNA within a chromosome has been flipped 180 degrees. Which type of mutation is this?
A researcher identifies a mutation where a segment of DNA within a chromosome has been flipped 180 degrees. Which type of mutation is this?
Which type of chromosomal mutation involves the exchange of DNA segments between two non-homologous chromosomes?
Which type of chromosomal mutation involves the exchange of DNA segments between two non-homologous chromosomes?
What term describes an individual with two different alleles for a particular gene?
What term describes an individual with two different alleles for a particular gene?
A geneticist is analyzing a patient's karyotype and notices that chromosome 2 and chromosome 9 have exchanged segments. There's no apparent gain or loss of genetic material. Which of the following is the most likely type of mutation?
A geneticist is analyzing a patient's karyotype and notices that chromosome 2 and chromosome 9 have exchanged segments. There's no apparent gain or loss of genetic material. Which of the following is the most likely type of mutation?
In a Punnett square, what do the inner boxes represent?
In a Punnett square, what do the inner boxes represent?
Which scientist(s) demonstrated that genes are located on chromosomes through experiments with Drosophila melanogaster?
Which scientist(s) demonstrated that genes are located on chromosomes through experiments with Drosophila melanogaster?
What is the function of restriction enzymes in recombinant DNA technology?
What is the function of restriction enzymes in recombinant DNA technology?
Reverse transcriptase is an enzyme that performs which of the following functions?
Reverse transcriptase is an enzyme that performs which of the following functions?
What is the primary application of Polymerase Chain Reaction (PCR)?
What is the primary application of Polymerase Chain Reaction (PCR)?
Consider a scenario where a researcher aims to insert a human gene into a bacterial plasmid. After successfully isolating both the gene of interest and the plasmid, which enzyme is indispensable for creating a stable, recombinant DNA molecule?
Consider a scenario where a researcher aims to insert a human gene into a bacterial plasmid. After successfully isolating both the gene of interest and the plasmid, which enzyme is indispensable for creating a stable, recombinant DNA molecule?
What is the total number of chromosomes found in a typical human diploid cell?
What is the total number of chromosomes found in a typical human diploid cell?
Which best describes the arrangement of genes on a chromosome?
Which best describes the arrangement of genes on a chromosome?
Approximately what percentage of the human genome is composed of genes (coding DNA)?
Approximately what percentage of the human genome is composed of genes (coding DNA)?
What is the primary function of histone proteins in chromosome structure?
What is the primary function of histone proteins in chromosome structure?
During which phase of the cell cycle are chromosomes most tightly condensed and visible under a light microscope?
During which phase of the cell cycle are chromosomes most tightly condensed and visible under a light microscope?
What distinguishes chromatin from a condensed mitotic chromosome?
What distinguishes chromatin from a condensed mitotic chromosome?
A researcher isolates a cell and finds it contains 23 chromosomes. This cell is MOST likely a:
A researcher isolates a cell and finds it contains 23 chromosomes. This cell is MOST likely a:
A geneticist is studying a newly discovered gene and determines that it contains 1.2 x 10^6 base pairs. Given that the haploid human genome contains approximately 3 x 10^9 base pairs, what percentage of the haploid genome does this gene represent?
A geneticist is studying a newly discovered gene and determines that it contains 1.2 x 10^6 base pairs. Given that the haploid human genome contains approximately 3 x 10^9 base pairs, what percentage of the haploid genome does this gene represent?
Which type of chromosomal mutation involves a segment of a chromosome being removed and then reinserted in the reverse orientation?
Which type of chromosomal mutation involves a segment of a chromosome being removed and then reinserted in the reverse orientation?
A genetic mutation results in the following change to the mRNA sequence: 5'-AUG UUC AGU-3' to 5'-AUG UUC UGA-3'. What type of point mutation is most likely responsible for this change?
A genetic mutation results in the following change to the mRNA sequence: 5'-AUG UUC AGU-3' to 5'-AUG UUC UGA-3'. What type of point mutation is most likely responsible for this change?
A researcher is studying a new gene and observes that an insertion mutation has occurred, adding a single base pair within the coding region. Which of the following is the most likely consequence of this mutation?
A researcher is studying a new gene and observes that an insertion mutation has occurred, adding a single base pair within the coding region. Which of the following is the most likely consequence of this mutation?
Which of the following mutations is least likely to have a significant impact on the function of the encoded protein?
Which of the following mutations is least likely to have a significant impact on the function of the encoded protein?
Considering the intricate mechanisms of DNA repair and the redundancy of the genetic code, what is the probability that a single base pair mutation in a non-coding, intronic region of a human gene will result in a phenotypic change detectable at the organismal level, assuming no other mutations are present?
Considering the intricate mechanisms of DNA repair and the redundancy of the genetic code, what is the probability that a single base pair mutation in a non-coding, intronic region of a human gene will result in a phenotypic change detectable at the organismal level, assuming no other mutations are present?
During meiosis I, what structure is formed at the site of crossing-over between homologous chromosomes?
During meiosis I, what structure is formed at the site of crossing-over between homologous chromosomes?
In which phase of meiosis do homologous chromosomes separate, leading to a reduction in chromosome number?
In which phase of meiosis do homologous chromosomes separate, leading to a reduction in chromosome number?
Unlike mitosis, during metaphase I of meiosis, a unique configuration is observed regarding kinetochore attachment. Which of the following accurately describes this?
Unlike mitosis, during metaphase I of meiosis, a unique configuration is observed regarding kinetochore attachment. Which of the following accurately describes this?
What is the primary significance of crossing over during prophase I of meiosis?
What is the primary significance of crossing over during prophase I of meiosis?
Which phase of meiosis is most similar to the phases of mitosis in terms of the events that occur?
Which phase of meiosis is most similar to the phases of mitosis in terms of the events that occur?
If sister chromatids were to separate during anaphase I of meiosis instead of anaphase II, what would be the most immediate consequence for the resulting daughter cells?
If sister chromatids were to separate during anaphase I of meiosis instead of anaphase II, what would be the most immediate consequence for the resulting daughter cells?
Throughout meiosis I, sister chromatids remain joined at their centromeres. What is the functional significance of this cohesion until anaphase II?
Throughout meiosis I, sister chromatids remain joined at their centromeres. What is the functional significance of this cohesion until anaphase II?
In mitosis, each sister chromatid's kinetochore attaches to spindle fibers from opposite poles. How does kinetochore attachment in meiosis I fundamentally differ from this, and what is the direct functional outcome of this difference?
In mitosis, each sister chromatid's kinetochore attaches to spindle fibers from opposite poles. How does kinetochore attachment in meiosis I fundamentally differ from this, and what is the direct functional outcome of this difference?
Post DNA replication and chromosome condensation, what is the configuration of a mitotic chromosome?
Post DNA replication and chromosome condensation, what is the configuration of a mitotic chromosome?
Which of the following cellular functions is MOST directly dependent on the information encoded within chromosomes?
Which of the following cellular functions is MOST directly dependent on the information encoded within chromosomes?
During meiosis, chromosomes are segregated to produce gametes. What is the PRIMARY purpose of this segregation?
During meiosis, chromosomes are segregated to produce gametes. What is the PRIMARY purpose of this segregation?
In the context of the central dogma of molecular biology, reverse transcriptase, an enzyme found in certain viruses, catalyzes which of the following reactions?
In the context of the central dogma of molecular biology, reverse transcriptase, an enzyme found in certain viruses, catalyzes which of the following reactions?
Consider a hypothetical scenario in which a novel synthetic molecule is introduced into a cell, selectively disrupting the function of ribosomal RNA (rRNA). What immediate downstream effect would most likely be observed?
Consider a hypothetical scenario in which a novel synthetic molecule is introduced into a cell, selectively disrupting the function of ribosomal RNA (rRNA). What immediate downstream effect would most likely be observed?
A chromosome breaks, and a fragment reattaches to the original chromosome in reverse order. Which type of chromosomal mutation is this?
A chromosome breaks, and a fragment reattaches to the original chromosome in reverse order. Which type of chromosomal mutation is this?
A point mutation causes a codon to change from coding for an amino acid to a stop codon. What type of point mutation is this?
A point mutation causes a codon to change from coding for an amino acid to a stop codon. What type of point mutation is this?
Which of the following mutations would least likely result in a frameshift?
Which of the following mutations would least likely result in a frameshift?
During genetic sequencing, a researcher identifies a mutation in a coding region of a gene that does not alter the amino acid sequence of the resulting protein. Which of the following best describes this type of mutation?
During genetic sequencing, a researcher identifies a mutation in a coding region of a gene that does not alter the amino acid sequence of the resulting protein. Which of the following best describes this type of mutation?
In a hypothetical scenario, a novel tRNA modification enzyme malfunctions, leading to misreading of the genetic code during translation. One specific codon, normally coding for serine, is now frequently misinterpreted as alanine. Assuming no other cellular mechanisms compensate for this error, what would be the most likely long-term consequence on the proteome of the affected organism, considering the chemical properties of serine and alanine?
In a hypothetical scenario, a novel tRNA modification enzyme malfunctions, leading to misreading of the genetic code during translation. One specific codon, normally coding for serine, is now frequently misinterpreted as alanine. Assuming no other cellular mechanisms compensate for this error, what would be the most likely long-term consequence on the proteome of the affected organism, considering the chemical properties of serine and alanine?
What is the role of chiasmata during meiosis I?
What is the role of chiasmata during meiosis I?
During metaphase I of meiosis, how do the kinetochores of a condensed chromosome attach to the spindle fibers?
During metaphase I of meiosis, how do the kinetochores of a condensed chromosome attach to the spindle fibers?
Which of the following events is unique to meiosis I, distinguishing it from mitosis?
Which of the following events is unique to meiosis I, distinguishing it from mitosis?
What is the consequence if sister chromatids separate during anaphase I instead of anaphase II?
What is the consequence if sister chromatids separate during anaphase I instead of anaphase II?
During which phase of meiosis do sister chromatids finally separate?
During which phase of meiosis do sister chromatids finally separate?
Which of the following best describes the outcome of meiosis I?
Which of the following best describes the outcome of meiosis I?
Which of the following phases of meiosis most closely resembles the events of mitosis?
Which of the following phases of meiosis most closely resembles the events of mitosis?
Imagine a scenario where, due to a cellular error, the cohesin complex fails to maintain the cohesion of sister chromatids throughout meiosis I. Assuming this error does not trigger cell cycle arrest, what is the most likely downstream consequence regarding chromosome segregation?
Imagine a scenario where, due to a cellular error, the cohesin complex fails to maintain the cohesion of sister chromatids throughout meiosis I. Assuming this error does not trigger cell cycle arrest, what is the most likely downstream consequence regarding chromosome segregation?
Which of the following correctly ranks the severity of mutation effects, from most to least severe?
Which of the following correctly ranks the severity of mutation effects, from most to least severe?
Sickle-cell anemia results from a single point mutation in the gene encoding hemoglobin B. This mutation leads to which of the following consequences?
Sickle-cell anemia results from a single point mutation in the gene encoding hemoglobin B. This mutation leads to which of the following consequences?
House-keeping genes are expressed by all cells continuously. What is a likely characteristic of house-keeping genes?
House-keeping genes are expressed by all cells continuously. What is a likely characteristic of house-keeping genes?
Epigenetic modifications, such as DNA methylation and histone modification, lead to altered expressions of genes. Which of the following is an accurate description of epigenetic modifications?
Epigenetic modifications, such as DNA methylation and histone modification, lead to altered expressions of genes. Which of the following is an accurate description of epigenetic modifications?
Mitochondrial inheritance differs significantly from nuclear inheritance. A genetic counselor is advising a family with a history of a mitochondrial disorder. Which of the following statements accurately describes mitochondrial inheritance?
Mitochondrial inheritance differs significantly from nuclear inheritance. A genetic counselor is advising a family with a history of a mitochondrial disorder. Which of the following statements accurately describes mitochondrial inheritance?
Which of the following best describes the primary purpose of the S phase within the cell cycle?
Which of the following best describes the primary purpose of the S phase within the cell cycle?
At which stage of mitosis are the condensed mitotic chromosomes, each consisting of two sister chromatids, aligned along the equatorial plane of the cell?
At which stage of mitosis are the condensed mitotic chromosomes, each consisting of two sister chromatids, aligned along the equatorial plane of the cell?
What event characterizes anaphase during both mitosis and meiosis II?
What event characterizes anaphase during both mitosis and meiosis II?
Which of the following events occurs during telophase?
Which of the following events occurs during telophase?
What is the ploidy of somatic cells in humans, and how do they typically reproduce?
What is the ploidy of somatic cells in humans, and how do they typically reproduce?
What is the correct number of chromosomes in a human gamete, and how are gametes produced?
What is the correct number of chromosomes in a human gamete, and how are gametes produced?
What is the immediate result of sperm and egg fusing?
What is the immediate result of sperm and egg fusing?
What cellular process reduces the chromosome number from diploid to haploid?
What cellular process reduces the chromosome number from diploid to haploid?
How many haploid cells are produced from one diploid germline cell after meiosis?
How many haploid cells are produced from one diploid germline cell after meiosis?
During what specific phase of meiosis does synapsis occur?
During what specific phase of meiosis does synapsis occur?
During which stage of meiosis does crossing over contribute to genetic variation?
During which stage of meiosis does crossing over contribute to genetic variation?
What is the direct result of the independent assortment of chromosomes during metaphase I?
What is the direct result of the independent assortment of chromosomes during metaphase I?
Why are mutations in gamete DNA considered inheritable?
Why are mutations in gamete DNA considered inheritable?
What is the function of DNA polymerase during DNA replication?
What is the function of DNA polymerase during DNA replication?
Which of the following chromosomal abnormalities leads to a trisomic individual?
Which of the following chromosomal abnormalities leads to a trisomic individual?
A man with a known chromosomal translocation is phenotypically normal, yet during meiosis, his chromosomes misalign, leading to unbalanced gametes with partial duplications and deletions. If he and a woman with a normal karyotype conceive, what is the most likely outcome for their offspring?
A man with a known chromosomal translocation is phenotypically normal, yet during meiosis, his chromosomes misalign, leading to unbalanced gametes with partial duplications and deletions. If he and a woman with a normal karyotype conceive, what is the most likely outcome for their offspring?
A researcher is investigating a gene responsible for regulating metabolism. They discover a mutation in a gene that encodes a protein which binds to a specific region of DNA to enhance transcription. This mutation significantly reduces the protein's binding affinity. What is the most likely outcome?
A researcher is investigating a gene responsible for regulating metabolism. They discover a mutation in a gene that encodes a protein which binds to a specific region of DNA to enhance transcription. This mutation significantly reduces the protein's binding affinity. What is the most likely outcome?
A couple, both phenotypically normal, have a child diagnosed with a rare recessive genetic disorder. After genetic counseling, they discover that each parent carries a loss-of-function mutation in the same gene but on different chromosomes. Further analysis reveals that the wild-type gene product is essential for the correct folding of another protein expressed in the cytoplasm. Given that the wild-type protein level is just sufficient for proper folding under normal circumstances, what is the most likely mechanism leading to the child's affected phenotype?
A couple, both phenotypically normal, have a child diagnosed with a rare recessive genetic disorder. After genetic counseling, they discover that each parent carries a loss-of-function mutation in the same gene but on different chromosomes. Further analysis reveals that the wild-type gene product is essential for the correct folding of another protein expressed in the cytoplasm. Given that the wild-type protein level is just sufficient for proper folding under normal circumstances, what is the most likely mechanism leading to the child's affected phenotype?
What does it mean to be homozygous?
What does it mean to be homozygous?
What is a key function of Histone proteins?
What is a key function of Histone proteins?
What holds the two DNA strands together?
What holds the two DNA strands together?
Which type of cell undergoes Mitosis?
Which type of cell undergoes Mitosis?
Which phase of cell division occurs first?
Which phase of cell division occurs first?
Flashcards
Allele Inheritance
Allele Inheritance
Each individual inherits two alleles for each gene, one from each parent.
Genotype
Genotype
The genetic makeup of an individual, describing the specific alleles they possess.
Phenotype
Phenotype
The observable traits or characteristics of an individual, determined by the genotype.
Homozygous
Homozygous
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Heterozygous
Heterozygous
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Punnett Square
Punnett Square
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Restriction Enzymes
Restriction Enzymes
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Polymerase Chain Reaction (PCR)
Polymerase Chain Reaction (PCR)
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Mitotic Chromosome Composition
Mitotic Chromosome Composition
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Gene Function
Gene Function
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Mitosis
Mitosis
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Meiosis
Meiosis
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DNA vs. RNA Function
DNA vs. RNA Function
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Diploid Cells
Diploid Cells
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Haploid Cells
Haploid Cells
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Genome
Genome
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Gene
Gene
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Locus
Locus
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Chromatin
Chromatin
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Nucleosome
Nucleosome
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Condensed Chromosomes
Condensed Chromosomes
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Karyotype
Karyotype
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Karyotyping Use
Karyotyping Use
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Insertions (genetics)
Insertions (genetics)
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Deletions (genetics)
Deletions (genetics)
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Inversions (genetics)
Inversions (genetics)
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Crossing Over
Crossing Over
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Chiasmata
Chiasmata
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Metaphase I Uniqueness
Metaphase I Uniqueness
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Sister Chromatids I
Sister Chromatids I
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Meiosis I Segregation
Meiosis I Segregation
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Meiosis II Segregation
Meiosis II Segregation
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Anaphase II
Anaphase II
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Meiosis Character
Meiosis Character
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Deletion (chromosomal)
Deletion (chromosomal)
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Point Mutation
Point Mutation
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Silent Mutation
Silent Mutation
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Nonsense Mutation
Nonsense Mutation
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Missense Mutation
Missense Mutation
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Centromere
Centromere
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Chromosome Arms
Chromosome Arms
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DNA Replication
DNA Replication
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Deoxyribonucleic Acid (DNA)
Deoxyribonucleic Acid (DNA)
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Duplication (chromosomal)
Duplication (chromosomal)
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Inversion (chromosomal)
Inversion (chromosomal)
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Translocation (chromosomal)
Translocation (chromosomal)
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Frameshift Mutation
Frameshift Mutation
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Mutation Severity Order
Mutation Severity Order
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Sickle-Cell Anemia
Sickle-Cell Anemia
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Epigenetics
Epigenetics
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Meiosis Outcome
Meiosis Outcome
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Independent Assortment
Independent Assortment
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Mutation
Mutation
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Mutagens
Mutagens
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DNA Repair Enzymes
DNA Repair Enzymes
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Trisomic
Trisomic
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Monosomic
Monosomic
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Homologous Recombination
Homologous Recombination
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Metaphase I Attachment
Metaphase I Attachment
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Sister Chromatid Cohesion (Meiosis I)
Sister Chromatid Cohesion (Meiosis I)
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Meiosis II Outcome
Meiosis II Outcome
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Anaphase II Separation
Anaphase II Separation
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Meiosis I Uniqueness
Meiosis I Uniqueness
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Cell Cycle
Cell Cycle
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S Phase
S Phase
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M Phase
M Phase
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C Phase
C Phase
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Kinetochore
Kinetochore
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Prophase
Prophase
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Metaphase
Metaphase
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Synapsis
Synapsis
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Autosomal Recessive
Autosomal Recessive
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Histone Proteins
Histone Proteins
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Meiosis II
Meiosis II
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DNA Polymerase
DNA Polymerase
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Reverse Transcriptase
Reverse Transcriptase
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Gene Therapy
Gene Therapy
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Taq Polymerase
Taq Polymerase
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Genetic Variation (Meiosis)
Genetic Variation (Meiosis)
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Transcription
Transcription
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Translation
Translation
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Transcription
Transcription
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DNA Structure
DNA Structure
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No Frameshift
No Frameshift
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Heterozygous Expression
Heterozygous Expression
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RNA vs. DNA Bases
RNA vs. DNA Bases
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Post-Transcriptional Splicing
Post-Transcriptional Splicing
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Diploid
Diploid
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Allele
Allele
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Reverse Transcription
Reverse Transcription
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ADA Gene Therapy
ADA Gene Therapy
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Chromosome Replication
Chromosome Replication
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Meiosis Location
Meiosis Location
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Ribosome Function
Ribosome Function
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Sickle-Cell Mutation
Sickle-Cell Mutation
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What is an Allele?
What is an Allele?
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Study Notes
Okay, I can do that for you, here are the updated study notes:
The Birth of Genetics
- Gregor Mendel is considered the "Father of modern genetics."
- Mendel, an Austrian Augustine monk, studied trait inheritance in garden pea plants from 1822-1884.
- Mendel analyzed the results of plant crosses not only by describing them but by counting and analyzing numbers.
- Mendel described simple trait inheritance and variation.
Genetic Definitions
- Genetics: the study of heredity and the variation of inherited characteristics.
- Traits: physical appearance or characteristic of an organism that may be inherited, environmentally determined, or a combination of both.
- Inherited traits or characteristics, are determined by inherited genes.
Mendel's Studied Traits
- Each trait studied had 2 alternate forms and variations.
- Each trait form was determined by a unique allele, with little influence from the environment.
- Allele: alternate version of a gene.
Mendel's Model of Heredity
- Gene: information for a trait passed from parents to offspring, Genes cause the trait.
- Genes correspond to specific DNA segments.
- Alleles: alternate versions of a gene, are designated by a letter, with the dominant allele as capital and the recessive allele as lowercase.
- Dominant alleles (such as P) produce dominant traits, like the purple flower, while recessive alleles (such as p) produce recessive traits, like the white flower.
- Different alleles have differences in their DNA sequences.
- Each individual receives two alleles, copies of each gene, from the father's sperm and the mother's egg or ovum.
- The alleles an individual possesses, is the genotype, determines what traits are exhibited, phenotype.
- A true-breeding purple flower has a PP genotype and a purple flower phenotype.
- Alleles don't seem to blend or change as they are transmitted to offspring.
- A particular allele's presence does not ensure its trait will appear; recessive allele traits can be masked.
- Mendel described the simplest form of trait inheritence in sexual animals and plants, called Mendelian Genetics.
- Homozygous: individual with two identical alleles and Homo of Greek origin means same.
- Homozygous dominant is PP and the true-breeding purple flower plant.
- Homozygous recessive is pp and the true-breeding white flower plant.
- Heterozygous: individual with two alleles that are different and Hetero of Greek origin means different
- Pp heterozygous is the purple hybrid plant and not true-breeding.
- The white flower trait of p is masked.
Punnett Square Analysis
- Punnett Square Analysis can show the results of a genetic cross.
- Possible alleles in pollen or egg are indicated in the outside boxes of the square.
- The inner boxes represent plants that could be formed, specifically when the intersecting male pollen fertilizes the intersecting female egg.
Discovering the Gene
- In the 1910s, Thomas Hunt Morgan showed that genes are found in chromosomes through experiments with Drosophila melanogaster, fruit flies.
- From 1920s-1940s, DNA was determined to be the molecule containing our genes.
- In 1953 Watson & Crick solved and described the molecular structure of DNA: Two strands of DNA base pair to form a double helix.
Recent Advances in Molecular Biology
- In the 1970s: Recombinant DNA Technology was further researched,
- Restriction enzymes were discovered to cut DNA at specific sequences, which allowed for the formation of DNA fragment patterns and DNA fingerprinting.
- Enzymes were discovered to chemically link two DNA fragments back together with ligases.
- Cloning vectors, bacterial plasmid DNA that can be altered to carry specific genes, were further investigated.
- Discovery of reverse transcriptase, an enzyme that can produce a DNA copy of an RNA molecule, was discovered.
- In the 1980's: a method was developed for amplifying DNA, called Polymerase Chain Reaction or PCR, which allows DNA to be amplified quickly in a test tube.
- Faster research advances were possible, including DNA sequencing.
- Nucleic acid detection of microbial diseases was now possible.
- In the 1990's the Human Genome Sequencing Project completed in 2000.
- First Gene Therapy Trials also began for immunocompromised children where the correct allele, DNA, was inserted into hematopoeitic stem cells.
Recent Advances in Molecular Genetics
- Since 2000 there has been:
- Large scale systemic analysis of RNA in transcriptomics, proteins in proteomics, and metabolites in metabolomics.
- More identification of new genetic risk factors for diseases, and studies of how genes influence treatment responses.
- Also Next Generation Sequencing and Advances in Gene Mapping which enables the sequencing/mapping of individual genomes, such as 23 and me testing.
- This also has led to Personalized medicine, with customization of healthcare based on patient genetic information.
Basic Molecular Genetics
- Chromosome: Includes location, structure, and organization.
- Nucleic acids: DNA and RNA
- Includes structure, gene organization, DNA synthesis by replication, RNA synthesis by transcription, protein synthesis by mRNA translation, DNA mutation and repair.
- Also included are Mitosis and Meiosis.
The Nucleus
- The cell's genetic material, the chromosome, is located in the nucleus.
- The nucleus stores genetic material of the cell called DNA.
- It's surrounded by the nuclear envelope which contains two phospholipid bilayers, with inner and outer membranes, that contain nuclear pores.
- Nuclear pores permit the passage of molecules between the nucleus and cytoplasm; RNA can exit and nuclear proteins can enter.
- Inside lies nucleoplasm
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