Search results
Results from the WOW.Com Content Network
Aneuploidy is the presence of an abnormal number of chromosomes in a cell, for example a human somatic cell having 45 or 47 chromosomes instead of the usual 46. [1] [2] It does not include a difference of one or more complete sets of chromosomes. A cell with any number of complete chromosome sets is called a euploid cell. [1]
Aneuploidy of autosomes is not well tolerated and usually results in miscarriage of the developing fetus. Fetuses with aneuploidy of gene-rich chromosomes—such as chromosome 1 —never survive to term, [ 9 ] and fetuses with aneuploidy of gene-poor chromosomes—such as chromosome 21 — are still miscarried over 23% of the time. [ 10 ]
Aneuploidy is the state where one or more individual chromosomes of a normal set are absent or present in more than their usual number of copies (excluding the absence or presence of complete sets, which is considered euploidy). Unlike euploidy, aneuploid karyotypes will not be a multiple of the haploid number.
Normal cells make errors in chromosome segregation in 1% of cell divisions, whereas cells with CIN make these errors approximately 20% of cell divisions. Because aneuploidy is a common feature in tumour cells, the presence of aneuploidy in cells does not necessarily mean CIN is present; a high rate of errors is definitive of CIN. [6]
Anaphase lag is a consequence of an event during cell division where sister chromatids do not properly separate from each other because of improper spindle formation. [1] The chromosome or chromatid does not properly migrate during anaphase and the daughter cells will lose some genetic information.
Organisms in which a particular chromosome, or chromosome segment, is under- or over-represented are said to be aneuploid (from the Greek words meaning "not", "good", and "fold"). Aneuploidy refers to a numerical change in part of the chromosome set, whereas polyploidy refers to a numerical change in the whole set of chromosomes. [44]
Human anatomy, physiology, and biochemistry are basic medical sciences, which are generally taught to medical students in their first year at medical school. Human anatomy can be taught regionally or systemically; [ 1 ] that is, respectively, studying anatomy by bodily regions such as the head and chest, or studying by specific systems, such as ...
Gross anatomy is the study of structures large enough to be seen with the naked eye, and also includes superficial anatomy or surface anatomy, the study by sight of the external body features. Microscopic anatomy is the study of structures on a microscopic scale, along with histology (the study of tissues), and embryology (the study of an ...