What is prophase I of meiosis I?
Prophase I is the first stage of meiosis I, followed by prophase II, anaphase I, anaphase II, metaphase I and metaphase II. In order to understand Prophase I of meiosis I, one should be familiar with the terms associated with this process. Meiosis only occurs in eukaryote cells.
What is the first stage of meiosis called?
Stage 1: Leptotene. At this first stage of Prophase I of meiosis I chromosomes are visible under electron microscopy and look like ‘a string of beads’, where the beads are referred to as nucleosomes. If fully stretched out, some DNA may be nearly a centimeter long – much too large for a cell nucleolus.
When do sister chromatids appear during meiosis?
Contrast the genetic content and the origin of sister versus nonsister chromatids during their earliest appearance in prophase I of meiosis. Sister chromatids are genetically identical, except where mutations may have occurred during DNA replication.
What is the post S phase structure of replicated chromosomes?
are the "post-S phase" structure of replicated chromosomes. Because they are composed of two chromatids joined by a centromere, they are also called sister chromatids are synapsed homologous chromosomes, which are composed of four chromatids.
What is sister chromatid?
sister chromatids. - separate during anaphase of mitosis and anaphase II of meiosis. - contain identical nucleotide sequences prior to crossing over. homologous chromosomes. - separate during anaphase I of meiosis. - crossover between them contributes to genetic diversity. - in a pair, one is maternal origin and the other is paternal origin.
What are kinetochores?
kinetochores. - They are complex structures attached to the centromeres of chromosomes that bind to spindle microtubules. - They are required for the segregation of chromosomes during anaphase of mitosis or meiosis. synaptonemal complex.
How many chromosomes are in a mustard plant?
The diploid number of chromosomes in the mustard plant, Arabidopsis thaliana, is 10. Knowing this, answer the following questions about the stages of mitosis. How many chromosomes will be found in each cell during prophase?
Which part of the meiosis cycle is required for moving homologs to opposite sides of the poles?
microtubules. - they are required for moving homologs to opposite sides of the poles during anaphase I of meiosis. - They are filaments in mitotic and meiotic spindles. - They are required for moving sister chromatids to opposite sides of the poles during anaphase II of meiosis and anaphase of mitosis. cohesin protein.
How many copies of gene A are in AaBC?
AaBC (This gamete contains two copies of gene "A". Proper segregation would have separated A from a and allowed only one copy per gamete)
Which allele is dominant in peas?
In peas, the smooth allele is dominant over the wrinkled allele. A plant with round peas was crossed to a plant with wrinkled peas and all of the resulting plants had smooth peas. What are the genotypes of the parents in this cross?
Is independent assortment homozygous or heterozygous?
T/F. Independent assortment occurs only in cells that are heterozygous for two genes (AaBb) and not in cells that are completely homozygous (AABB or aabb).
