Calorie reduction lowers protein linked to the aging process
Reduced calorie intake has been shown to improve health and lifespan in laboratory animals, and recent research shows these benefits may extend to humans as well.
17 hours ago
0
171
Reduced calorie intake has been shown to improve health and lifespan in laboratory animals, and recent research shows these benefits may extend to humans as well.
17 hours ago
0
171
Understanding which cells give rise to which areas of cancer can improve our understanding of how a tumor has grown and developed, including how it has changed genetically over time. This has been made possible using a new ...
Aug 10, 2022
0
41
British health authorities said Friday the monkeypox outbreak across the country may be peaking and that the epidemic's growth rate has slowed.
Aug 05, 2022
0
6
Health Minister Mark Butler today announced Australia had secured 450,000 doses of a third-generation monkeypox vaccine, 22,000 of which will arrive later this week.
Aug 04, 2022
0
3
Right now, more than 1 in 10 Americans take medicines for depression—a number that has risen during the pandemic.
Jul 23, 2022
1
38
Changes that occur in the body in response to an increase in belly fat have been put under the microscope as part of a study from TwinsUK, offering new insight into the cause of metabolic disease.
Jul 19, 2022
0
3
The discovery of 14 inherited genetic changes which significantly increase the risk of a person developing a symptomless blood disorder associated with the onset of some types of cancer and heart disease is published today ...
Jul 14, 2022
0
83
To date most research on obesity has focused on studying those with a high body mass index (BMI), but a research group in China is taking a different approach. In a study published July 14 in the journal Cell Metabolism, ...
Jul 14, 2022
1
165
Using new technologies to study thousands of genes simultaneously within immune cells, researchers at Gladstone Institutes, UC San Francisco (UCSF), and Stanford School of Medicine have created the most detailed map yet of ...
Jul 11, 2022
0
101
A new study reveals why a highly infectious variant of the cholera bug, which caused large disease outbreaks in the early 1990s, did not cause the eighth cholera pandemic as feared—but instead unexpectedly disappeared.
Jul 05, 2022
0
75
In biology, mutations are changes to the nucleotide sequence of the genetic material of an organism. Mutations can be caused by copying errors in the genetic material during cell division, by exposure to ultraviolet or ionizing radiation, chemical mutagens, or viruses, or can be induced by the organism itself, by cellular processes such as hypermutation. In multicellular organisms with dedicated reproductive cells, mutations can be subdivided into germ line mutations, which can be passed on to descendants through the reproductive cells, and somatic mutations, which involve cells outside the dedicated reproductive group and which are not usually transmitted to descendants. If the organism can reproduce asexually through mechanisms such as cuttings or budding the distinction can become blurred. For example, plants can sometimes transmit somatic mutations to their descendants asexually or sexually where flower buds develop in somatically mutated parts of plants. A new mutation that was not inherited from either parent is called a de novo mutation. The source of the mutation is unrelated to the consequence, although the consequences are related to which cells were mutated.
Mutations create variation within the gene pool. Less favorable (or deleterious) mutations can be reduced in frequency in the gene pool by natural selection, while more favorable (beneficial or advantageous) mutations may accumulate and result in adaptive evolutionary changes. For example, a butterfly may produce offspring with new mutations. The majority of these mutations will have no effect; but one might change the color of one of the butterfly's offspring, making it harder (or easier) for predators to see. If this color change is advantageous, the chance of this butterfly surviving and producing its own offspring are a little better, and over time the number of butterflies with this mutation may form a larger percentage of the population.
Neutral mutations are defined as mutations whose effects do not influence the fitness of an individual. These can accumulate over time due to genetic drift. It is believed that the overwhelming majority of mutations have no significant effect on an organism's fitness. Also, DNA repair mechanisms are able to mend most changes before they become permanent mutations, and many organisms have mechanisms for eliminating otherwise permanently mutated somatic cells.
Mutation is generally accepted by the scientific community as the mechanism upon which natural selection acts, providing the advantageous new traits that survive and multiply in offspring or disadvantageous traits that die out with weaker organisms.
This text uses material from Wikipedia, licensed under CC BY-SA