In the nucleus of each cell, the DNA molecule is packaged into thread-like structures called chromosomes. Each chromosome is made up of DNA tightly coiled many times around proteins called histones that support its structure.
Chromosomes are not visible in the cell’s nucleus—not even under a microscope—when the cell is not dividing. However, the DNA that makes up chromosomes becomes more tightly packed during cell division and is then visible under a microscope. Most of what researchers know about chromosomes was learned by observing chromosomes during cell division.
Each chromosome has a constriction point called the centromere, which divides the chromosome into two sections, or “arms.” The short arm of the chromosome is labeled the “p arm.” The long arm of the chromosome is labeled the “q arm.” The location of the centromere on each chromosome gives the chromosome its characteristic shape, and can be used to help describe the location of specific genes.
A new study has unraveled a genetic vulnerability that exists in almost 10% of all breast cancer tumors.
The evolution of sex chromosomes is of crucial importance in biology as it stabilises the mechanism underlying sex determination and usually results in an equal sex ratio.
Bacterial speck disease, which reduces both fruit yield and quality, has been a growing problem in tomatoes over the last five years.
According to neuroscientists, misfiring brain cells that regulate vital parts of the tongue and mouth might be creating swallowing problems in kids.
Representing some of the most troublesome agricultural weeds, waterhemp, smooth pigweed, and Palmer amaranth impact crop production systems across the U.S. and elsewhere with ripple effects felt by economies worldwide.
The African baobab tree (Adansonia digitata) is called the tree of life. Baobab trees can live for more than a thousand years and provide food, livestock fodder, medicinal compounds, and raw materials. Baobab trees are incredibly significant. However, there are growing conservation concerns and until now, a lack of genetic information
A new study shows how differentiation of a single gene changes behavior in a wild songbird, determining whether the white-throated sparrow displays more, or less, aggression.
It can be hard to dispute the common adage 'survival of the fittest'. After all, "most of the genes in the genome are there because they're doing something good," says Sarah Zanders, PhD, assistant investigator at the Stowers Institute for Medical Research
Researchers at Massachusetts General Hospital (MGH) have solved a mystery that has long puzzled scientists: How do the bodies of female humans and all other mammals decide which of the two X chromosomes it carries in each cell should be active and which one should be silent?
Biological sex is typically understood in binary terms: male and female. However, there are many examples of animals that are able to modify sex-typical biological and behavioral features and even change sex.
All life is subject to evolution in the form of mutations that change the DNA sequence of an organism's offspring, after which natural selection allows the 'fittest' mutants to survive and pass on their genes to future generations.
The Y chromosome, which is relatively smaller than its counterpart, the X chromosome, has significantly reduced in size across 200 million years of evolution.
Scientists from Harvard University, CNAG, and CRG have demonstrated a pioneering technology that helps observe hundreds of genomes under the microscope.
Virginia Tech scientists have revealed how a nonfunctioning version of an ordinary gene impairs brain structure and function. The findings help explain a genetic form of microcephaly -- a condition where babies' heads are small and grow more slowly than their peers.
Current observations suggest that the coronavirus SARS-CoV-2 causes severe symptoms mainly in elderly patients with chronic disease.
Cell division is a fundamental process that organisms need to reproduce, grow, and make repairs. But when an error disrupts this complex biological process, cellular abnormalities can lead to diseases, such as cancer, where cells are enabled to grow and divide out of control.
A novel technology that integrates machine learning and high-throughput imaging could accelerate drug discovery to fight tuberculosis (TB).
A research group centered around Kobe University Graduate School of Medicine's Professor YAMADA Hideto and Associate Professor TANIMURA Kenji (Department of Obstetrics and Gynecology), and Professor ARASE Hisashi et al. of Osaka University's Research Institute for Microbial Diseases have revealed for the first time in the world the high frequency of a novel autoantibody in women suffering from recurrent pregnancy loss.
For the first time, scientists at the Morgridge Institute for Research have generated near atomic resolution images of a major viral protein complex responsible for replicating the RNA genome of a member of the positive-strand RNA viruses, the large class of viruses that includes coronaviruses and many other pathogens.
Two rereading proteins on the DNA assembly line collectively work as an emergency stop button to inhibit replication errors.