Podcast
Questions and Answers
What important event must take place during interphase before a cell proceeds to division?
What important event must take place during interphase before a cell proceeds to division?
DNA replication must take place during interphase before.
What two structures make up a single replicated chromosome?
What two structures make up a single replicated chromosome?
Sister chromatids make up a single replicated chromosome.
How many replicated chromosomes does the cell contain during prophase?
How many replicated chromosomes does the cell contain during prophase?
The cell contains 4 replicated chromosomes during prophase.
At what stage in meiosis I do the pairs of homologous chromosomes come together?
At what stage in meiosis I do the pairs of homologous chromosomes come together?
Once the chromosomes have formed a pair, what are they called?
Once the chromosomes have formed a pair, what are they called?
At the end of meiosis I, two cells have been produced. How many chromosomes are in each of these cells?
At the end of meiosis I, two cells have been produced. How many chromosomes are in each of these cells?
At what stages of meiosis I are the cells diploid and at what stages are they haploid?
At what stages of meiosis I are the cells diploid and at what stages are they haploid?
Describe the relationship between the cells at the end of telophase I and the original cell.
Describe the relationship between the cells at the end of telophase I and the original cell.
Will the cells at the end of telophase I be genetically identical to each other?
Will the cells at the end of telophase I be genetically identical to each other?
In meiosis I, during anaphase I, which structures separated—homologous chromosomes or sister chromatids?
In meiosis I, during anaphase I, which structures separated—homologous chromosomes or sister chromatids?
During anaphase II, what structures separated: sister chromatids or homologous chromosomes?
During anaphase II, what structures separated: sister chromatids or homologous chromosomes?
At the end of meiosis II, are there four daughter cells that are haploid or diploid?
At the end of meiosis II, are there four daughter cells that are haploid or diploid?
Describe the relationship between the cells at the end of meiosis II and the original cell.
Describe the relationship between the cells at the end of meiosis II and the original cell.
When does crossing over occur in meiosis?
When does crossing over occur in meiosis?
When the chromosomes come together as homologous pairs, what are the crossover points called?
When the chromosomes come together as homologous pairs, what are the crossover points called?
Describe what happens to the chromatids during crossover.
Describe what happens to the chromatids during crossover.
What phrase is used to describe the chromatids after crossing over takes place and the homologous chromosomes separate?
What phrase is used to describe the chromatids after crossing over takes place and the homologous chromosomes separate?
Are the genes on a recombinant chromatid the same as the original chromatid?
Are the genes on a recombinant chromatid the same as the original chromatid?
Are the alleles on a recombinant chromatid the same as the original chromatid?
Are the alleles on a recombinant chromatid the same as the original chromatid?
If there were three sets of homologous chromosomes in the cell, how many possible arrangements would there be for the tetrads in late prophase I?
If there were three sets of homologous chromosomes in the cell, how many possible arrangements would there be for the tetrads in late prophase I?
Explain how meiotic events, as well as the random fertilization of eggs and sperm, together lead to genetic variation.
Explain how meiotic events, as well as the random fertilization of eggs and sperm, together lead to genetic variation.
Flashcards
What must happen before a cell divides?
What must happen before a cell divides?
DNA replication must take place during interphase before a cell proceeds to division.
What makes up a replicated chromosome?
What makes up a replicated chromosome?
Sister chromatids make up a single replicated chromosome.
How many chromosomes in prophase?
How many chromosomes in prophase?
The cell contains 4 replicated chromosomes during prophase.
When do homologous chromosomes pair up?
When do homologous chromosomes pair up?
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What is the name for a pair of homologous chromosomes?
What is the name for a pair of homologous chromosomes?
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How many chromosomes after meiosis I?
How many chromosomes after meiosis I?
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When are cells diploid/haploid in meiosis I?
When are cells diploid/haploid in meiosis I?
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Relationship between cells after meiosis I?
Relationship between cells after meiosis I?
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Are cells after meiosis I genetically identical?
Are cells after meiosis I genetically identical?
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What separates during anaphase I?
What separates during anaphase I?
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What separates during anaphase II?
What separates during anaphase II?
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Are cells after meiosis II haploid?
Are cells after meiosis II haploid?
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Relationship between cells after meiosis II?
Relationship between cells after meiosis II?
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When does crossing over occur?
When does crossing over occur?
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What is the name for the crossover points?
What is the name for the crossover points?
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What happens during crossing over?
What happens during crossing over?
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What is the name for chromatids after crossing over?
What is the name for chromatids after crossing over?
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Are genes the same on recombinant chromatids?
Are genes the same on recombinant chromatids?
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Are alleles the same on recombinant chromatids?
Are alleles the same on recombinant chromatids?
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How many arrangements if 3 sets of homologous chromosomes?
How many arrangements if 3 sets of homologous chromosomes?
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How do meiotic events and fertilization lead to genetic variation?
How do meiotic events and fertilization lead to genetic variation?
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Study Notes
Meiosis Overview
- DNA replication occurs during interphase, essential before cell division.
- A single replicated chromosome comprises two sister chromatids.
Chromosome Count in Meiosis
- During prophase, a cell contains 4 replicated chromosomes.
- At the end of meiosis I, each of the two resulting cells has 2 chromosomes.
Homologous Chromosomes and Meiosis Stages
- Homologous chromosome pairs come together at the end of prophase I, forming tetrads.
- Cells are diploid during prophase, metaphase, and anaphase, and shift to haploid after telophase I when two cells divide to form four.
Genetic Information Post-Meiosis
- Cells at the end of telophase I contain half of the genetic information of the original cell, meaning they are not genetically identical due to different alleles on separated homologous pairs.
- At the end of meiosis II, four daughter cells are haploid, each with one chromosome pair.
Crossing Over and Genetic Variation
- Crossing over occurs during prophase I, allowing chromatids to exchange genetic material.
- Crossover points where chromatids interact are known as chiasmata.
- The resulting chromatids post-crossover are referred to as recombinant chromatids.
Alleles and Genes on Chromatids
- Genes on recombinant chromatids remain the same as original chromatids but may possess different alleles due to the switch during crossover.
- The likelihood of different arrangements during tetrad formation is significant, with 8 potential configurations for three sets of homologous chromosomes.
Role of Random Fertilization
- Genetic variation is enhanced by random fertilization of eggs and sperm, influenced by the random assortment of alleles during meiosis.
- Each zygote created through fertilization has a unique genetic makeup, underscoring the diversity in offspring.
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Description
Test your knowledge on key events of meiosis with this set of flashcards. Understand the processes that occur during interphase and the structure of replicated chromosomes. Perfect for students studying cell division.