Sow Flashcards
What occurs during Prophase I of meiosis?
Chromosomes condense, nuclear envelope dismantles, homologous chromosomes pair, diploid cell with double chromatids is present
Prophase I is critical for genetic recombination.
What is the key event happening in Metaphase I?
Homologous chromosomes align at the cell equator, diploid cell with double chromatids
This alignment is crucial for proper chromosome segregation.
What happens during Anaphase I?
Separation of homologous chromosomes to opposite poles, formation of two haploid cells with double chromatids
This stage reduces the chromosome number by half.
What occurs in Telophase I?
Two chromosome sets at each pole, cytoplasm divides equally, formation of two haploid cells with double chromatids
This marks the end of the first meiotic division.
What characterizes Prophase II?
Individualized chromosomes in each cell, haploid cells with double chromatids
This phase prepares the cells for the second meiotic division.
What happens during Metaphase II?
Chromosomes align at the equator, haploid cells with double chromatids
Similar to Metaphase I but involves haploid cells.
What is the key event in Anaphase II?
Separation of chromatids after centromere rupture, migration of identical chromosome sets to opposite poles, formation of four new haploid cells with single chromatids
This step completes the meiotic process.
What occurs during Telophase II?
Formation of nuclear envelope around each set, chromosomes decondense, cytoplasm divides into four haploid daughter cells with single chromatids
This concludes meiosis, resulting in gametes.
Define Brassage Interchromosomique.
Genetic mixing occurring between Prophase I and Metaphase I, involving independent genes on different chromosome pairs
It leads to various genetic combinations due to random alignment.
What is Brassage Intrachromosomique?
Mixing of linked genes on the same chromosome pair through crossing-over between Prophase I and Metaphase I
This process generates new allele combinations.
What is the significance of fertilization?
Random union of two gametes increases genetic mixing, represented by a Punnett square for future zygote allele combinations
This process enhances genetic diversity.
Fill in the blank: Meiosis generates _______ haploid cells crucial for sexual reproduction.
four
These cells are gametes that participate in fertilization.
True or False: Genetic diversity is only influenced by meiosis.
False
Genetic diversity is also influenced by fertilization and environmental factors.
What are the two main types of genetic mixing during meiosis?
- Brassage Interchromosomique
- Brassage Intrachromosomique
Both processes contribute to the genetic variability of offspring.
What is the overall conclusion regarding meiosis?
Meiosis, through two successive divisions, generates genetic diversity essential for species evolution
This diversity is critical for adaptation and survival in changing environments.
