7
votes
1answer
773 views

What is this beetle and what are the strange antennae for?

I found this wonderful creature in my yard (I live in the south of France) last night: It was about 2-3cm long, with a hard carapace and wings. It also made loud hissing noises when agitated. I ...
6
votes
2answers
536 views

Is this species a variant of a red flour beetle?

Found this little guy crawling around the back garden - South Coast of the UK. The closest things I could find online (with an admittedly weak knowledge of where to look up these things, aside a ...
7
votes
1answer
2k views

Why do pigeons kill their chicks when touched by a human?

I used to have many pigeons around the house. If by chance one of the chicks fell out of the nest, we used to put it back using gloves. Usually, if we would touch the chicks with our bare hands, ...
2
votes
2answers
114 views

Why a continuous supply of energy is needed to support a weight?

What motivates this question is the apparent discrepancy between the concept of Work in physics and in physiology. Work in physics is defined as the dot product of the force applied to move a certain ...
6
votes
1answer
83 views

Can dolphins actually communicate linguistically?

Humans use "language." By language, I mean the thing I am using right now to talk to you. I know dolphins and orcas have very complex communication systems and also seem to process linguistic and ...
1
vote
1answer
197 views

Can all animals of the same species crossbreed?

For example, take Canis lupus, the species of dog and wolf. Within their species, can all dog and wolf types crossbreed? We can forget the logistics and assume this is all done through artificial ...
4
votes
1answer
871 views

Cause of Crease in Drupe Fruit

What causes the crease through the pericarp of a drupe fruit (peach, nectarine, olive)? It may just be in exocarp as @Ilan pointed out, but I assumed (perhaps wrongly), that the division continued ...
5
votes
3answers
236 views

How can a ligand be an integral membrane protein?

My background is in mathematics, and not biology, so please bear with me. I am currently working on a project involving the effects of Epidermal growth factor treatment (EGF) on cell migration. I am ...
1
vote
2answers
166 views

Introductory book in genetics? [duplicate]

I am working in the field of neuroscience with a background in computer science. I try to find new ways of analyzing brain imaging data (mostly MRI, EEG, MEG, fMRI) with modern machine learning ...
2
votes
1answer
34 views

Do we have evidence of heritable personality traits in chimpanzees?

I have read that chimpanizees have distinct personalities. Do we have evidence of heritable personality traits in them?
3
votes
1answer
1k views

What is the difference between Single Nucleotide Polymorphism (SNP), Mutation and Structural Variation(SV)?

This is a question which plagues many people and today I was wondering it myself while writing a grant. Indeed, I've seen many people use the terms interchangeably, but they are all very different ...
4
votes
1answer
659 views

What is the optimum length of abstinence for maximum ejaculation volume in humans?

There have been papers discussing this, and whether the abstinence period should be 1 week, 2 weeks or other [1, 2]. Some think the time to maximum ejaculation volume is even longer than this. doi: ...
1
vote
1answer
3k views

Bacterial capsule vs. slime wall

I've read that the bacterial capsule protects the bacterium from phagocytes and prevents water (and nutrients, possibly?) leakage from the bacterium. A less organized and less dense version is called ...
2
votes
1answer
301 views

What is the chemical composition of an egg shell?

It ought to be some combination of C, O, and H, I presume. But really why should I care if eggshell gets in my eggs while I'm cooking?
1
vote
3answers
257 views

Trypsin and cell culture

I am doing an experiment where I have treat the cells with a drug and calculate their counts. I would like to know if is bad to trypsinize the cells in consecutive days i.e. twice within 48 hours. How ...
5
votes
5answers
97 views

Can an influenza virus carry other infectors with it?

This idea came to my mind when thinking about how many people become ill in many locations with similar symptoms (fever and rough cough) from Influenza. There are of course different types of ...
1
vote
0answers
140 views

Different names in paired-end sequence files

I am aligning paired end sequence reads using bwa mem and I get an error saying that ...
5
votes
3answers
186 views

Can we knock out Caspase-9 *and* avoid breast cancer phenotype in our mouse model?

I am trying to design a wet lab experiment with no wet lab experience to name. Right now, in my dream land, it would be excellent if it were possible to create a Caspase-9 knockout mouse (damage to ...
10
votes
1answer
1k views

What is the mass of a pigeon tail feather?

There is question at Space.SE If I drop a feather from orbit, would it burn up or “hit” the ground? there is an attempt to answer the question, but the mass of pigeon tail feather and possibly the ...
3
votes
1answer
116 views

What is the genomic position of HLA-B*1502 variation?

I've searched the position and SNP ID of HLA-B*1502 variation. However, I couldn't find that where this variant exactly located on genome or HLA-B gene.
0
votes
1answer
2k views

How to calculate biological half life of a drug that is dose dependent?

I would like to calculate the half-life of a biological drug. This biological drug is said to have a biological half-life of: ...
2
votes
1answer
40 views

MTHFR recessive alleles and B-vitamins

I know that being heterozygous or homozygous recessive for the MTHFR gene prevents that person from being able to process and use folate and B-12. It causes an unhealthy level of homocysteine to ...
5
votes
1answer
517 views

Time spent in phases of cell cycle

I am looking for references to papers containing the time intervals spent in different phases of the cell cycle (ej., G0, G1, S, G2, M for eukaryotes) for different cells. In particular, I am ...
1
vote
1answer
42 views

Mitochondrial inner membrane

I know that the cristae of the inner membrane can be tubular or vesicular but I would like to know what are the functions of each .
6
votes
1answer
117 views

Are there terrestrial plants that thrive on sea water?

Given the existence of coastal deserts such as in the picture below, I was wondering whether terrestrial plants can survive on sea water alone? If yes, why then do coastal deserts exist, instead of ...
3
votes
1answer
39 views

How high into the air are spores of molds commonly occurring?

I understand so far that most of the air surrounding us contains mold spores so that given the right environment and a food source they start to grow. I assume this is true for air close to the earth. ...
3
votes
1answer
49 views

What makes a strong polyadenylation signal a strong signal?

I was wondering why is it that "AAUAAA" is a strong Polyadenylation signal whereas the rest of the polyadenylation signals show reduced cleavage and polyadenylation efficiency?
2
votes
1answer
108 views

Consequence of Plants as Incomplete Protein Source

Some years ago, in a 1000~ level biology course we learned that the DNA essentially encodes formulas for creating proteins from amino acids. While the human body can synthesize many many amino acids, ...
11
votes
4answers
7k views

Will the heart keep beating if it is separated from the body?

The heart is a vital organ in our body, as it drives blood circulation. I was wondering if a heart keeps beating if it is separated from the body? If yes, then why?
13
votes
4answers
10k views

Are trees the only source of large amounts of oxygen?

Trees use carbon dioxide and produce oxygen in the presence of sunlight. But is there any other source? If yes, are trees the most important source of oxygen, or is there any other source which ...
0
votes
0answers
38 views

To what extent do different species of plants help each other in the defense against herbivores?

Many plant species developed the ability to sense mechanical damage and herbivory attacks. In case of such, some produces airborne chemicals (among others), to signal not only it's other parts, but ...
1
vote
1answer
79 views

Leaves growing on a leaf of a Begonia

I've a Begonia species. Somehow it started to grow new leaves on top and right in the center of an existing leaf which you can see in the center of the image. Why is it doing this? Apparently it is ...
5
votes
1answer
78 views

Identify the plant

Can anyone tell me which plant or flower is this. I have found it in Darjeeling, West Bengal, India.
2
votes
1answer
71 views

How do I find the number of child terms associated with a specific GO term?

I am trying to figure out how to find the number of child terms associated with a specific Gene Ontology (GO) term using QuickGO, without just counting the amount of terms in a list. For example when ...
3
votes
0answers
43 views

Expected reproduction rate of a dandelion and/or fern

I am working a basic mathematical/computer simulation of an ecosystem, and I need to know the birth rate of each organism in my simulation. However, I could not find any data for how often a small, ...
17
votes
3answers
6k views

Are humans the only animal that requires “clean water”?

I've seen a number of animals - dogs, cats, squirrels, ducks and geese, etc drink from puddles, some of them were muddy, others had green flora growing under water. Same goes for lakes and rivers. A ...
1
vote
0answers
58 views

Is there a comprehensive model of human attraction and sexuality? [closed]

I'm interested if modern (2015) biology has a comprehensive model of how human sexuality works. From my research, it appears that the drive for mating is primarily mediated by ...
0
votes
1answer
112 views

How can succinylcholine cause myorelaxation?

I first thought that this is because of prolonged depolarisations. However, I am not sure anymore, because after reading PubChem, the only possible pathways are are Choline agonist. So I would say ...
5
votes
1answer
42 views

One Sample, Different Methylation Values

I'm hoping that somebody here can explain this unusual result that I'm getting with some pyrosequencing data. I have bisulphite converted a few samples a couple of times over the years for different ...
2
votes
2answers
218 views

Value of mathematical models in biology [closed]

Sorry if this is too much of a soft question or if it is too broad for this site. As a person who has much more experience with math than biology, I've always been really interested in the ...
1
vote
0answers
31 views

Can photosyntetic cells be genetically modified to grow at a faster rate?

I hope the question is not silly, but I wonder if a sort of genetically modified plant "cancer" could be used for carbon sequestration. For example, cancer cells like HeLa have been reproduced in ...
0
votes
1answer
385 views

Choosing a book to gain general knowledge about biology [duplicate]

I will be first year undergraduate at Physics department next year and last year I was at the Medicine faculty. I want do double major in the second year of faculty with Molecular Biology and ...
21
votes
2answers
2k views

Can rats pass on memories of a maze to their offspring?

A friend of mine told me once about a documentary movie he saw some years ago. On this movie he saw scientists talking about particular experiment. This experiment involved rats and probably ...
3
votes
2answers
265 views

Neomycin resistance gene in E. coli stb3 cells

We use a lentivirus packaging vector called pLenti_puro_DEST. We use puromycin to select for the cloned gene in 293T cells. However, the pLenti_Neo_Dest has been discontinued, so I'm cloning a ...
3
votes
0answers
19 views

Gene silencing: relative or absolute number of methylated CpG sites?

CpG content varies a lot across the human genome. What does determine a promoter to be silenced through DNA methylation: the fraction of CpG sites that are methylated or the total number of methylated ...
4
votes
2answers
2k views

Is secondary follicle or Graafian follicle arrested in the second metaphase of oogenesis?

My note about which I am not sure: Secondary oocyte is arrested in the metaphase II monthly after puberty until fertilization with sperm. The following picture also satisfies my sentence: . So ...
4
votes
1answer
129 views

Is the autonomic nervous system only activated by internal stimuli?

My professor claims that the autonomic nervous system is only activated by stimuli from organs but I really feel like I've read that it can be activated by outside stimuli, although I'm not sure what ...
11
votes
2answers
463 views

Can we make a rough estimate of the number of generations since the origin of life?

According to what we've learnt : we can approximate the number of generations since the first human pretty much like us (depending what / who we talk about). we have an idea of the series of life ...
3
votes
1answer
158 views

Pigmentation in Jaundice

My textbook says that the yellow appearance of a jaundiced person is due to the accumulation of bile pigments in the skin. I am unable to understand why these pigments are not deposited in a healthy ...
4
votes
1answer
211 views

Why do some protocols require prewarming a liquid medium before inoculating?

For example, in this protocol for E. coli competent cell preparation, it says: Plate 10 uL E. coli BL21(DE3) cells on a LB-agar plate; incubate overnight (12 hours). Prepare 500 mL SOB medium ...

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