18

Short answer: Chimpanzees are indeed closer, but perhaps...too close. Almost all invasive research on non-human great apes has halted for some time over ethical concerns. Rhesus macaques are the main non-human primate still used in research (some others are also used, like marmosets). "Pretty much the closest" is in reference to which species are available ...


12

It is not like someone painted a zebra one color (say white) and then painted lines of the other color (say black) on top. But it does not mean we can't give some thoughts on the question. What causes these patterns? The colors are caused by pigments. Melanocytes either produce black pigments or do not and this cause the alternation of white and black ...


11

It is naïve to think that the extent of protein similarity is sufficient to determine what is the best animal model for a human disease. The physiology of the animal and the question of compensatory genes are all factors that contribute. Indeed, if the protein is functionally similar, it may be irrelevant if it has diverged in other regions. And, of course,...


8

Zebra embryos start off black and develop white stripes late in development. This is widely used to conclude that zebras are actually black with white stripes, and it's as good an argument as any for this essentially semantic question.


7

There are many seabirds smaller than partridges. The smallest seabird (according to the National Trust of Scotland) is the European Storm Petrel, which weighs in at an average of 28g. That's not quite as small as the European Wren (6 - 10 g), but it definitely counts as 'small', nonetheless. Being seabirds which spend their life at sea except during ...


5

Mice are mammals, like humans, so their proteins tend to show more homology with human proteins than non-mammalian options. They are also actually more closely related to humans than cats or dogs due to the relatively recent (~80 million year) separation of lineages that led to modern rodents and primates. Mice breed fairly quickly year-round and have ...


5

Such genome transplantation was performed between two Mycoplasma species in Craig Venter institute Genome transplantation in bacteria: changing one species to another. They found that the donor genome completely changes the recipient cell to accept the identity of the original donor cell. Note of caution: the above experiment was conducted between two ...


4

Biology is a large field of knowledge! As you give examples drawn from population biology (logistic population growth and Lotka-Voltera models), I will assume you are mainly interested in ecology and evolution. For analytical models used in ecology and evolution, I highly recommend the book A Biologist's Guide to Mathematical Modeling in Ecology and ...


4

The IHH gene encodes the Indian hedgehog homolog protein, a member of the family of hedgehog proteins that regulates bone formation. The ihh-/- notation represents an animal which is homozygous for a null mutation in the gene (i.e. the animal has no functional IHH gene).


4

Yeah, it's not good: Social isolation (SI) rearing in rodents causes a variety of behavioral changes, including hyperlocomotion, anxiety, impulsivity, aggression, and learning and memory deficits. These behavioral abnormalities in rodents may be related to the symptoms in patients with neuropsychiatric disorders, such as attention-deficit hyperactivity ...


3

The Cotton Pigmy Goose for example is about 26 cm long and weight about 160grams (smaller than a grey partridge) can take off and land on water. Have a look at this video for example. As @WYSIWYG said, any young of "water fowl" species are small and are still "water fowls". I would also bet that if you put a dead hummingbird on standing water, it would ...


3

959 Somatic Cells according to WormBase and The WormBook.


3

The animal is very suggestive for Dog whelk-like mollusc removed from its shell. I try to mark the organs, do not rely on these marks as an absolut. Testis Renal vein Gill Mantle Prostate Osphradium 10 and others - digestive and reproductive systems, cannot mark precisely. Digestive gland source for comparing etc


3

These are allele notations or nomenclatures and they refer to a gene, and what changes a particular gene has undergone, if any. In this case, the -/- refers to the fact that the Ihh gene is homozygous for a null mutation as correctly stated by @Alan Boyd. This page has further examples of allele nomenclatures. This page, which can be reached from the ...


3

Why do bird sing? The main reason, male bird sing to attract mates (often, only males sing). Birds may also sing to communicate to their peers. For example a song can mean "This is my territory, you'd better not approach!". There are other reasons birds can sing (although I think I cited the two most important ones); you'll find much more information if you ...


2

The evidence shows that the tusk is innervated, and acts as a sensory organ to the outside environment, as well as a mating tool. Sensory ability in the narwhal tooth organ system


2

The answers are: Yes, they know when to stop eating. See this paper. Yes, they store extra energy as fat in the intestine. This one is a little more complicated. They can use extra energy, but not to move faster. Movement doesn't take much energy, and until they're close to death from starvation, they continue to move quite well. As for eggs, they do indeed ...


2

Dpy is a class of genes. Usually they're written in lowercase when referring to a mutant allele. The name Dpy itself stands for dumpy and comes from the morphological change that occurs when one or more of the genes are mutated: the worms appear short and fat, or dumpy. Another big class is Unc. Mutations in those genes cause uncoordinated movement. For ...


2

In my opinion the terms inducible and conditional are synonyms. Together with the term constitutive they refer to how transcription takes place, that is, the second phase in the central dogma that states that genetic information is propagated from replication to transcription to translation. The proteins that are produced during translation by ribosomes can ...


2

From personal experience, it should be sufficient to observe zebrafish at 10-20x magnification for broad structural changes during development. If your microscope has a 10x eyepiece, then that would be 1-2x zoom. If you are observing sub-cellular changes, you would benefit from higher magnification.


2

Your second interpretation is correct. The mice have been reconstituted from stem cells that were "transduced" (using a viral vector) with a construct containing the appropriate geneX. The link gives comparison of transduction vs. transfection. https://www.vectalys.com/blog/what-are-the-differences-between-transfection-and-transduction-222


2

There is no super-term that I can think of but you could say genetically modified (mouse) samples/specimens?


2

I don't think you missed anything important! You could investigate the cyclic behaviour around the equilibrium. For example, looking at the variable aphid population size can start above its equilibrium point, then overshoot it and overshoot it again to finally reach the equilibrium point. If you zoom close to the equilibrium point, you might see long ...


1

Intravenous delivery of pathogen produces infection more efficiently than transmucosal delivery. 10^7 is 2 orders of magnitude less than 10^9. It is not the volume that is different (although it may be), it is CFUs or "colony forming units" which is a proxy for viable pathogens in the inoculum. The oral dose is 100x that of the IV. Getting germs directly ...


1

Short answer is no. Human disease take a long time to develop naturally, far longer than the lifespan of animals models used (mice, rats or fish). Also the cost of the drugs far exceed the cost of the animal. There is little point in spending $40k to make a non-commercial anti cancer drug to save the life of a pet mouse who has developed the rare cancer. ...


1

Yes, in the fields population dynamics/ecology, the standard predator-prey system is routinely described in terms of a negative feedback loop. See e.g. Lewontin & Levins, 2007 for an online exemple (the term is commonly found in articles and textbooks though).


1

From my experience, "negative feedback" is more often used in the context of processes in the body which attenuate themselves or in the context of stimuli and sensors. However predator-prey dynamics could fit the general definition of the term. In general, negative feedback is just when a process or output of a system leads back into the system to attenuate ...


1

technically speaking, Large hadron Collider allowed humans to sense quite a bit of information about particles. Also, we can sense pretty well how electrons and photons behave, using other tools. We even can sense how they behave in absence of particles (it's called theoretical physics). Closer to your point, however, it is verified that human eye (and ...


1

Typically when working with compounds I come from two directions: Does the drug appear in the literature and what concentration do they use? I think a quick literature search is a wonderful thing because like many problems, often times someone else has asked your question (what's the right concentration?), and done the necessary legwork to find you a ...


1

The Cochrane Collaboration has a great deal of this type of analysis. One of my favourite features of a Cochrane Review is the routine use of Funnel Plots, where there are sufficient data to produce them. Sensible interpretation of funnel plots can give some fairly strong hints about the reproducibility of published literature. Funnel plots show datapoints ...


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