Unit 30C Cell Division, Genetics, and Molecular
... For most cells, the nuclear division that occurs during mitosis marks only a small part of their cycle. The stage between division phases, called interphase, is marked by a period of rapid growth (gap 1, or G1), the duplication of chromosomes (synthesis, or S), another period of growth (gap 2, or G2 ...
... For most cells, the nuclear division that occurs during mitosis marks only a small part of their cycle. The stage between division phases, called interphase, is marked by a period of rapid growth (gap 1, or G1), the duplication of chromosomes (synthesis, or S), another period of growth (gap 2, or G2 ...
The genomic landscape of meiotic crossovers and gene
... eLife digest Most living organisms package their DNA into bundles called chromosomes. These chromosomes generally form pairs, with each chromosome in the pair containing the same number of genes. The genes also come in the same order, but the exact sequence of DNA bases within the genes can be diffe ...
... eLife digest Most living organisms package their DNA into bundles called chromosomes. These chromosomes generally form pairs, with each chromosome in the pair containing the same number of genes. The genes also come in the same order, but the exact sequence of DNA bases within the genes can be diffe ...
View PDF - G3: Genes | Genomes | Genetics
... the data, we compared the genetic composition of four pairs of segregants derived from each ascus such that each pair represented adjoining spores in the ascus. Among the nine linear asci analyzed, 21 among 36 pairs were discordant for alleles of at least one among the four markers; two of them were ...
... the data, we compared the genetic composition of four pairs of segregants derived from each ascus such that each pair represented adjoining spores in the ascus. Among the nine linear asci analyzed, 21 among 36 pairs were discordant for alleles of at least one among the four markers; two of them were ...
MOLECULAR CYTOGENETIC ANALYSES IN WHEAT AND
... make detailed studies on the degree of relationship between the various plant species and varieties and on their genome structures. In recent decades many results have been achieved in this field. Basic breeding material with more favourable agronomic properties have been developed carrying genes or ...
... make detailed studies on the degree of relationship between the various plant species and varieties and on their genome structures. In recent decades many results have been achieved in this field. Basic breeding material with more favourable agronomic properties have been developed carrying genes or ...
My PP Genetics
... determine traits consist of two separate alleles. Half of the sex cells an individual produces carry one allele, and the other half carry the second ...
... determine traits consist of two separate alleles. Half of the sex cells an individual produces carry one allele, and the other half carry the second ...
Cot-1 banding of human chromosomes using fluorescence
... to chromosome spreads (Lichter et al., 1988, 1990a, 1990b). Particularly, its use for gene mapping by the fluorescence in situ hybridization (FISH) becomes increasingly important. However, little is known about the relationship between the human Cot-1 DNA and the conventional chromosome banding such ...
... to chromosome spreads (Lichter et al., 1988, 1990a, 1990b). Particularly, its use for gene mapping by the fluorescence in situ hybridization (FISH) becomes increasingly important. However, little is known about the relationship between the human Cot-1 DNA and the conventional chromosome banding such ...
THE EFFECT OF STRUCTURAL HETEROZYGOSITY ON
... This apparent reduction in crossing-over potential agrees with a similar observation based upon cytological data by DOYLE (1960). The testcross results for the two types of interspecific duplexes (Tables 1 and 2) show that the presence of the inversion exerts an important effect on the degree of pre ...
... This apparent reduction in crossing-over potential agrees with a similar observation based upon cytological data by DOYLE (1960). The testcross results for the two types of interspecific duplexes (Tables 1 and 2) show that the presence of the inversion exerts an important effect on the degree of pre ...
Dragon Investigations
... From Genotypes to Phenotypes: Teacher Information For Question 1, from “Dragon Genetics” (the left box at the top of the preceding page) you know that male dragons are XX and female dragons are XY. From “Two Dragon Genotypes” (the right box at the top of the preceding page) you can see that Sandy h ...
... From Genotypes to Phenotypes: Teacher Information For Question 1, from “Dragon Genetics” (the left box at the top of the preceding page) you know that male dragons are XX and female dragons are XY. From “Two Dragon Genotypes” (the right box at the top of the preceding page) you can see that Sandy h ...
Forche et al. 2008 PLoS Biology
... precisely halve the DNA content in the cell, often for the formation of haploid gametes from diploid precursor cells. This specialized form of cell division involves one round of DNA replication followed by two successive rounds of DNA division. Each round of DNA division is unique. During the first ...
... precisely halve the DNA content in the cell, often for the formation of haploid gametes from diploid precursor cells. This specialized form of cell division involves one round of DNA replication followed by two successive rounds of DNA division. Each round of DNA division is unique. During the first ...
The Parasexual Cycle in Candida albicans Provides an
... precisely halve the DNA content in the cell, often for the formation of haploid gametes from diploid precursor cells. This specialized form of cell division involves one round of DNA replication followed by two successive rounds of DNA division. Each round of DNA division is unique. During the first ...
... precisely halve the DNA content in the cell, often for the formation of haploid gametes from diploid precursor cells. This specialized form of cell division involves one round of DNA replication followed by two successive rounds of DNA division. Each round of DNA division is unique. During the first ...
Pairing of homologous regions in the mouse genome is associated
... factor binding to cis regulatory regions, modifications of DNA and chromatin, position of the gene in nuclear space, and an intricate network of chromosome associations in trans determine the expression state of a particular gene. Often, co-regulated genes are found in the same transcription factory ...
... factor binding to cis regulatory regions, modifications of DNA and chromatin, position of the gene in nuclear space, and an intricate network of chromosome associations in trans determine the expression state of a particular gene. Often, co-regulated genes are found in the same transcription factory ...
Haploids and Doubled Haploids in Plant Breeding
... numbers of haploids from any genotype. Pollination with maize is also effective for inducing haploid embryos in several other cereals, such as barley, triticale (x Triticosecale), rye (Secale cereale) and oats (Avena sativa) (Wędzony, 2009). Similar processes of paternal chromosome elimination occur ...
... numbers of haploids from any genotype. Pollination with maize is also effective for inducing haploid embryos in several other cereals, such as barley, triticale (x Triticosecale), rye (Secale cereale) and oats (Avena sativa) (Wędzony, 2009). Similar processes of paternal chromosome elimination occur ...
Do gametes woo? Evidence for non-random unions at
... The most prominent exceptions to random segregation are the rare naturally-occurring examples of transmission ratio distortion (TRD) that have been described in fungi,4 corn,5 flies,6-10 mice,1116 humans,17, 18 and other species.19-22 Biased sex ratios have also been reported.23-29 These exceptions ...
... The most prominent exceptions to random segregation are the rare naturally-occurring examples of transmission ratio distortion (TRD) that have been described in fungi,4 corn,5 flies,6-10 mice,1116 humans,17, 18 and other species.19-22 Biased sex ratios have also been reported.23-29 These exceptions ...
A Three-Dimensional Structural Dissection of Drosophila Polytene
... be maintained in structures that allow site-specific regulated transcription and temporally controlled DNA replication. Normally, it is not possible to resolve individual chromosomes in the interphase nucleus by light microscopy. However, due to the process of polytenization, the giant salivary glan ...
... be maintained in structures that allow site-specific regulated transcription and temporally controlled DNA replication. Normally, it is not possible to resolve individual chromosomes in the interphase nucleus by light microscopy. However, due to the process of polytenization, the giant salivary glan ...
6.3 Mendel and Heredity
... – Mendel used purebred pea plants. This meant that a line of pea plants had self-pollinated for so long that they were genetically uniform. – He was able to breed selectively by interrupting and controlling the pollination process. – Because he used purebred pea plants, he knew that any genetic vari ...
... – Mendel used purebred pea plants. This meant that a line of pea plants had self-pollinated for so long that they were genetically uniform. – He was able to breed selectively by interrupting and controlling the pollination process. – Because he used purebred pea plants, he knew that any genetic vari ...
Warm Up: Mon 8/1
... Atoms of the same element can have different numbers of neutrons; these variations of an element are called:______ An atom’s Atomic Number is equal to that element’s number of :______________ An element’s Atomic Mass is equal to its number of _________ plus its number of ...
... Atoms of the same element can have different numbers of neutrons; these variations of an element are called:______ An atom’s Atomic Number is equal to that element’s number of :______________ An element’s Atomic Mass is equal to its number of _________ plus its number of ...
1 Sister chromatids are often incompletely cohesed
... During preliminary investigations we occasionally found three or four instead of one or two FISH signals for chromosome-specific ~100 kb segments in 4C nuclei of A. thaliana indicating that not only homologues but also sister chromatids may occupy separate positions within a nucleus. Therefore, we b ...
... During preliminary investigations we occasionally found three or four instead of one or two FISH signals for chromosome-specific ~100 kb segments in 4C nuclei of A. thaliana indicating that not only homologues but also sister chromatids may occupy separate positions within a nucleus. Therefore, we b ...
LIST OF CHECK-UP QUESTIONS for
... a) are found in plant cells; b) have two membranes; c) contain DNA; d) are found in animal cells; CORRECT e) contain a matrix. 3. The way of formation of somatic cells in human body is: a) amitosis b) mitosis CORRECT c) meiosis d) gametogenesis 4. In what phase of the cell cycle the period when DNA ...
... a) are found in plant cells; b) have two membranes; c) contain DNA; d) are found in animal cells; CORRECT e) contain a matrix. 3. The way of formation of somatic cells in human body is: a) amitosis b) mitosis CORRECT c) meiosis d) gametogenesis 4. In what phase of the cell cycle the period when DNA ...
Deep Insight Section
... prevailed, namely trisomy 16 in one third of the cases, and trisomies 21, 22 and 15, each accounting for about 10 % of the lot, thus making up altogether some two thirds of the trisomies observed in these abortuses. And since, as a rule, meiotic mis-segregation must result in as many nullisomie as d ...
... prevailed, namely trisomy 16 in one third of the cases, and trisomies 21, 22 and 15, each accounting for about 10 % of the lot, thus making up altogether some two thirds of the trisomies observed in these abortuses. And since, as a rule, meiotic mis-segregation must result in as many nullisomie as d ...
Induced chromosome doubling in plants
... make up of the F 1 generation is more predictable. The inbreds With a desirable trait are generated by back-crossing a het ...
... make up of the F 1 generation is more predictable. The inbreds With a desirable trait are generated by back-crossing a het ...
Completion of a parasexual cycle in Candida
... traditionally been classi®ed as a diploid, asexual organism. However, mating-competent forms of the organism were recently described that produced tetraploid mating products. In principle, the C.albicans life cycle could be completed via a sexual process, via a parasexual mechanism, or by both mecha ...
... traditionally been classi®ed as a diploid, asexual organism. However, mating-competent forms of the organism were recently described that produced tetraploid mating products. In principle, the C.albicans life cycle could be completed via a sexual process, via a parasexual mechanism, or by both mecha ...
Evidence for Mitotic Crossing-over During the
... of chromosome 11. This diploid was temperature sensitive, white, and unable to produce haploid segregants capable of axenic growth, and had thus become homozygous for all four markers. But even here it is not necessary to invoke complete dupIication of a chromosome since a crossover event between th ...
... of chromosome 11. This diploid was temperature sensitive, white, and unable to produce haploid segregants capable of axenic growth, and had thus become homozygous for all four markers. But even here it is not necessary to invoke complete dupIication of a chromosome since a crossover event between th ...
Title: FISH analysis comparing the gene composition of the Onager
... Department of Biology, Crestview Hills, KY 41017, University of Kentucky2, M.H. Gluck Equine Research Center, Department of Veterinary Science, Lexington, KY 40546-0099, Conservation and Research for Endangered Species3, Zoological Society of San Diego, San Diego, CA 92027 The onager [E. hemionus on ...
... Department of Biology, Crestview Hills, KY 41017, University of Kentucky2, M.H. Gluck Equine Research Center, Department of Veterinary Science, Lexington, KY 40546-0099, Conservation and Research for Endangered Species3, Zoological Society of San Diego, San Diego, CA 92027 The onager [E. hemionus on ...
Mutants of the Drosophila ncd microtubule motor
... spindles in oocytes of ncd null mutants (Wald, 1936; Kimble and Church, 1983) has led to the idea that the primary defect is the oocyte microtubule organizing center (Kimble and Church, 1983). Localization of ncd to meiotic spindles from Drosophila oocytes (Hatsumi and Endow, 1992a) and the minus-en ...
... spindles in oocytes of ncd null mutants (Wald, 1936; Kimble and Church, 1983) has led to the idea that the primary defect is the oocyte microtubule organizing center (Kimble and Church, 1983). Localization of ncd to meiotic spindles from Drosophila oocytes (Hatsumi and Endow, 1992a) and the minus-en ...
Meiosis
Meiosis /maɪˈoʊsɨs/ is a specialized type of cell division which reduces the chromosome number by half. This process occurs in all sexually reproducing single-celled and multi-celled eukaryotes, including animals, plants, and fungi. Errors in meiosis resulting in aneuploidy are the leading known cause of miscarriage and the most frequent genetic cause of developmental disabilities. In meiosis, DNA replication is followed by two rounds of cell division to produce four daughter cells each with half the number of chromosomes as the original parent cell. The two meiotic divisions are known as meiosis I and meiosis II. Before meiosis begins, during S phase of the cell cycle, the DNA of each chromosome is replicated so that it consists of two identical sister chromatids. In meiosis I, homologous chromosomes pair with each other and can exchange genetic material in a process called chromosomal crossover. The homologous chromosomes are then segregated into two new daughter cells, each containing half the number of chromosomes as the parent cell. At the end of meiosis I, sister chromatids remain attached and may differ from one another if crossing-over occurred. In meiosis II, the two cells produced during meiosis I divide again. Sister chromatids segregate from one another to produce four total daughter cells. These cells can mature into various types of gametes such as ova, sperm, spores, or pollen.Because the number of chromosomes is halved during meiosis, gametes can fuse (i.e. fertilization) to form a zygote with a complete chromosome count containing a combination of paternal and maternal chromosomes. Thus, meiosis and fertilization facilitate sexual reproduction with successive generations maintaining the same number of chromosomes. For example, a typical diploid human cell contains 23 pairs of chromosomes (46 total, half of maternal origin and half of paternal origin). Meiosis produces haploid gametes with one set of 23 chromosomes. When two gametes (an egg and a sperm) fuse, the resulting zygote is once again diploid, with the mother and father each contributing 23 chromosomes. This same pattern, but not the same number of chromosomes, occurs in all organisms that utilize meiosis. Thus, if a species has 30 chromosomes in its somatic cells, it will produce gametes with 15 chromosomes.