Hot answers tagged

21

I found this post by Russ Altman quite good. Below is his opinion about the two similar but distinct fields: Computational biology: the study of biology using computational techniques. The goal is to learn new biology, knowledge about living sytems. It is about science. Bioinformatics: the creation of tools (algorithms, databases) that ...


19

When dealing with humans, there are only two Biological genders as defined by the presence or absence of the Y-Chromosome. If the Y-Chromosome is not present, or through some process gets totally deactivated, the human will appear and function as a Female. XX = Female XY = Male XXY = Male (Klinefelter's Syndrome) XYY = Male (Aneuploidy - Normal ...


17

I think you might be confusing sex and gender. The terms are often used interchangeably, but strictly speaking, they have different biological meanings. Sex refers to the biological categorization based on genetics, reproductive organs, or similar things, whereas gender is based on social identity. For humans, there are only two sex chromosomes, X and Y, ...


12

Such projections are more formally known as spiculations. Most commonly, we talk about spiculations with respect to the radiographic appearance of malignant breast and lung lesions. This paper* describes the correlation between the mammorgraphic appearance of spiculated breast lesions and their pathology (microscopic appearance), which is a reasonable start ...


12

The whole point of Darwin's theory was that transition from one species to another is extremely slow and gradual. There are plenty of quotes in "Origin of Species" stating this, and also affirming that there is no clear boundary between species and subspecies, or "races". Quotes from Origin of Species > Variation under Nature (Chapter 2) Quote 1 ...


10

I don't know if they are classified as organs, but basically, blood vessels match the criteria for being organs. Quoting SIU School of Medicine: Blood vessels are basically tubular organs found within other organs. Biology Reference states the same: Even the glands within the integument can be considered organs; any gland is primarily secretory ...


9

I think this question is on topic here, although yes you would definitely get a lot of answers at BioStars. But consider this from the bioinformatics tag wiki on this site. Bioinformatics is a broad field that interfaces a variety of life science disciplines (biology, genetics, biochemistry, biophysics, etc) with a variety of quantitative sciences (...


9

Bioavailability is a concept which applies to nutrients and drugs which pass through first-pass metabolism, i.e. orally (and to some extent nasally) consumed substances. Anything absorbed in the gut first passes through the liver before reaching the rest of the circulation, and both the gut and liver may metabolise it to some extent. The liver in specific ...


9

The cardiovascular system is usually lumped together as an organ. So blood vessels would be included here but you are right in that this is a bit strange being that it includes the heart and the vasculature.


7

This phenomenon is described as regressive evolution (the loss of a phenotypic trait). There are several reasons why this occurs: Neutral mutations which become fixed through genetic drift. Positive selection of regressive mutations that are beneficial. Pleiotropic antagonism: positive selection for one trait may have the consequence of disrupting ...


7

Detritivores consume (eat) detritus. Saprotrophs feed on dead organic matter by the means of extracellular digestion. Saprozoic organisms are protozoans that are saprotrophs. This actually comes from an obsolete classification of plants and animals where bacteria and fungi were grouped with plants and were therefore called saprophytes if they are ...


6

Cytokines is the general class of molecules to which chemokines, interferons, interleukins and others belong. Biologists dispute whether something is a hormone or a cytokine, but generally the consensus goes with if it's to do with immunology it's a cytokine or if the resting concentration is in the picomolar range, but that's a very rough distinction. ...


6

Aside from the actual microbial cells themselves, biofilms are a slime matrix made of a variety of substances, including DNA, lipids, proteins, and other signaling molecules, but the major component is something called extracellular polymeric substance (EPS), also known as exopolysaccharides. Succinoglycan from Sinorhizobium meliloti These are high ...


6

It seems to me that the difference is mainly semantic, although the aims of synthetic biology are undoubtedly more ambitious than those of genetic engineering in, say, the 80s and 90s. The Wikipedia page on genetic engineering has this definition of the difference: Synthetic biology is an emerging discipline that takes genetic engineering a step ...


6

Besides the etymologic explanation that @aandreev gave, in cell culture this term is commonly used to describe the density of adherent cells and it is used as a measure of their proliferation. It is usually combined with an estimated (or counted) percentage, so 10% confluency means that 10% of the surface the dish or flask used is covered with cells, 100% ...


6

Optical Density is synonymous with absorbance which is based on the principle of absorption of light. The machine that is used to measure absorbance is called a spectrophotometer. Spectrometer does not indicate that light absorbance is being measured. A spectrometer can measure any spectrum; for e.g. Mass Spectrometer measures the spectrum of molecular mass (...


6

They get used somewhat interchangeably, which blurs the lines on the definitions. When I had my anatomy classes, sinews were regarded as an inclusive class, which included both ligaments and tendons. For the breakdown: Tendon: Fibrous tissue that connects muscle to bone. Ligament: Fibrous tissue that connects bone to bone. Sinew: Includes both of the ...


6

If you read the lines immediately following your quoted line (on p.391, left column, last paragraph in the linked article) it becomes clear what relay competent means (and I quote): As a result, the cells sense and move toward a source of cAMP, and they relay the signal as well by secreting cAMP. [..] After about 8 h of starvation randomly located cells, ...


6

Broad means wide as in a wide range. Normally, antibodies have one epitope they recognize, i.e., one specific target; they are said to have a narrow range of targets. Some antibodies, however, recognize multiple targets, i.e. the number of targets they recognize is larger and their target range is widened. They are said to have a broad cross-...


6

Sexual Conflict is the word you are looking for! Sexual Conflict occurs whenever the optimal mating strategy for the female and the male differ. For example, in Drosophila, it is beneficial for a male to mate as much as possible, while it is beneficial for a female to mate only a few times.


5

The figure of 350 - 600 Units per mg refers to the specific activity of the enzyme. The Unit is International Unit or IU and is usually defined as that amount of enzyme that will catalyze the transformation of 1 micromole of substrate (or product) per min, under defined assay conditions (such as pH, temperature, substrate concentration, presence of Mg++, ...


5

From the page linked from your link: Unit Definition One unit will convert 1.0 μmole of phospho(enol)pyruvate to pyruvate per min at pH 7.6 at 37 °C. So, the unit is defined by activity, and there is no way to know how many molecules or milligrams of protein are included


5

I'm actually not sure myself. If I were to use something, I would go with "Mitos'd" and "Meios'd". However, you may not win over many fans, depending on the audience. If it's with students or maybe a professor, you could get away with shortening the processes. If it's in any formal setting, be as precise and descriptive as possible. It's not a lot of ...


5

How about "splicing fragments"? It might be easier to refer to them according to the mechanism of production.


5

Intelligence is something which has to have a definition, and there are many, but I would cautiously say no. The reason that I say this is because swarming behavior can be largely reproduced by a simple set of rules - matching distance to your neighbors and direction and speed as well. To me this really removes any intention or even conscious element to ...


5

I think the main question here is: Is there a term…which describes a bipolar disorder of lesser severity[?] Yes. There are a couple ways to think about this, but you’re clearly accustomed to differentiating the manic and depressive phases of bipolar disorder, so I’ll start with that. There is mania (excerpted from DSM 5*): A. A distinct period of ...


5

Short answer The distinction between Gram positive (Gram+) and negative bacteria (Gram-) has absolutely nothing to do with membrane potentials; it is all about the Gram staining procedure. Background The Gram staining was named after the Danish bacteriologist Hans Christian Gram, who originally devised it in 1882 (Gram, 1884). Gram staining is a common ...


5

No, not necessarily! The terms might be confusing I agree. The most common allele (the wild type allele) might be a mutant of one other type of allele (one mutant allele) present in the population. The reason we call the least common alleles the mutant alleles is that beneficial mutations are rare compared to neutral or deleterious mutations. If at a given ...


5

Short answer V stands for voltage. Background The various leads in an ECG montage are shown below: ECG electrodes. Source: American Heart Association I am not an expert in ECGs, but as far as I can see, RA, LA and LL are return electrodes as they are situated far away from the heart. In other words, they act as reference electrodes. RL is the ground, ...


5

Parasitism – a parasite that lives on or in an host, obtaining food from the host and harming it. Example: Ixodes ticks use white tailed deer as a host Parasite is smaller and weaker than the host Parasite may feed over the host from outside or inside In parasite-host relationship a weaker organism is benefitted Host specificity is more common The host ...



Only top voted, non community-wiki answers of a minimum length are eligible