Meiosis Worksheet Flashcards
What are the haploid and diploid numbers of chromosomes in humans?
How many are autosomes?
What are homologous chromosomes?
What are the sex chromosomes in males and females?
23 and 46
22 and 44
matching pair of maternal and paternal chromosomes
XY, XX
How does meiosis contribute to genetic diversity?
random assortment of chromosomes and recombination
What is the chromosome number and DNA content for each of the following?
diploid somatic cell in G1, diploid somatic cell in G2, gamete in prophase of MI, gamete in metaphase of MII, and haploid gamete
diploid somatic cell in G1: 2N, 2C diploid somatic cell in G2: 2N, 4C gamete in prophase of MI: 2N, 4C gamete in metaphase of MII: 1N, 2C haploid gamete: 1N, 1C
What are the stages of meiotic prophase?
Leptotene, Zygotene, Pachytene, Diplotene, and Diakenesis
What events occur that are specific to meiosis?
2 cellular divisions and recombination and homologous chromosome pairing (extended prophase)
What is the synaptonemal complex, and what is its function? How is chromosome pairing achieved in sex chromosomes?
a ladderlike series of proteins that aid in pairing and recombining chromosomes during meiosis; synaptonemal complex
Why is recombination necessary during meiosis? When does recombination occur during meiosis? What are chiasmata?
> genetic diversity
prophase I - completed by pachytene stage
places of crossover DNA that hold the homologous chromosomes together at the metaphase plate
When do homologous chromosomes segregate?
When do sister chromatids segregate?
Anaphase I
Anaphase II
What cell types in a diploid organism undergo meiosis? Why is this process essential for sexual reproduction?
gametes; ensures transmission of correct number of chr. to next generation