1
vote
1answer
43 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
33 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?
1
vote
0answers
28 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
133 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 ...
3
votes
1answer
59 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
votes
0answers
16 views

Using bwa mem with barcoded sequencing reads

I am using bwa mem to align paired end sequencing reads of mine. I have a 6bp barcode on both the 5' and 3' ends of my sequences that should be trimmed and added to the header for alignment. ...
9
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 ...
8
votes
3answers
163 views

Why are the organs for reproduction and urinary excretion combined?

We eat food for getting energy to our body parts, and we excrete the wastes through urine, feces, and perspiration. Why has nature combined the urinary tract with the genital system (urogenital ...
0
votes
1answer
115 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: ...
1
vote
2answers
66 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 ...
3
votes
1answer
61 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.
5
votes
1answer
48 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 ...
1
vote
3answers
72 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
2answers
51 views

Why is cisplatin a very potent antineoplastic for testicular cancer, but not necessarily for other cancers?

Cisplatin (structure below) is a platinum-based chemotherapeutic agent which is very effective in the treatment of some cancers. Its introduction was responsible for improving the cure rate for ...
2
votes
1answer
30 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. ...
1
vote
1answer
39 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
0answers
31 views

What is the fate of micronucleus DNA?

Micronuclei are cellular structures that are formed as a by-product of, usually, defective mitosis. The piece of chromosome in a micronucleus may, or may not contain a centromere and the DNA is ...
0
votes
0answers
24 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 ...
3
votes
1answer
37 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?
7
votes
1answer
121 views

If eating 100% fat 2 times more worth the energy I spend during the day, will I store body fat?

So in theory, insulin hormone is the one that tells the body "eat more. don't burn body fat". Alongside with glucose blood level regulation and turning excessive glucose into liver (which later goes ...
11
votes
4answers
2k 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 ...
2
votes
1answer
40 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 ...
2
votes
1answer
69 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, ...
2
votes
1answer
44 views

GATK workflow for Cancer

I am just starting to learn to use bioinformatics tools. My university has a limited and expensive bioinformatics team, so I'm mostly on my own except for big questions. I am planning to use GATK to ...
11
votes
4answers
1k 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?
1
vote
1answer
44 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 ...
3
votes
0answers
28 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, ...
3
votes
1answer
82 views

Do we need to drink less water in humid weather than in dry weather?

From my understanding, humid weather means that the air has a lot of water in it. Therefore, someone who lives in this kind of weather would be hydrating himself just by breathing. Does that mean ...
4
votes
1answer
63 views

Identify the plant

Can anyone tell me which plant or flower is this. I have found it in Darjeeling, West Bengal, India.
1
vote
0answers
35 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 ...
1
vote
0answers
26 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 ...
7
votes
1answer
76 views

What determines the number of chromosomes an organism carries?

This is an extension of this question about What limits chromosomal length?. I am wondering what could be the specific reasons behind the number of chromosomes an organism carries. In other words, ...
3
votes
0answers
14 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 ...
3
votes
2answers
49 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 ...
-1
votes
1answer
67 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 ...
4
votes
1answer
32 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 ...
11
votes
1answer
69 views

What limits chromosomal length?

What are the upper and lower limits for chromosome length? Are these limits different in different species or kingdoms? If there is any limit, which cellular or molecular factors are reasons?
5
votes
1answer
38 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 ...
6
votes
0answers
33 views

Following DNA replication during S-phase of the cell-cycle, are all genomic regions subjected to the same stringent level of DNA-Repair?

To my (limited) understanding, there are 2 main ways that mutations can occur in DNA: Environmental (UV, etc) and mistakes during cell division. I was wondering if there is a mechanism that can give ...
6
votes
0answers
33 views

What bacteria shed harvestable energy from root zone organic matter?

I recently heard of a successful effort that harvests energy from soil at plants' bases due to apparently bacterial breakdown of wastes from the plants: Via photosynthesis a plant produces organic ...
2
votes
1answer
46 views

Additive genetic variance $V_A= 2pqa^2$ … what is $a$?

Reading Falconer and Mackay looking at equation $V_A = 2pqa^2$ (equation 8.5, page 126). I am trying to write a clear explanation of how additive genetic variance is defined and calculated, but I ...
-3
votes
1answer
24 views

From where can I download the database created by Hsu et al for MORFs? [closed]

I am working on an independent research project for which I require access to the MORF database created by Hsu et al. From where can I download the database of MORFs of IDPs and their binding partners ...
2
votes
0answers
26 views

Falconer & Mackay population mean calculation & genotypic values

I am reading chapter 7 of Falconer and Mackay where they give a formula to calculate the population mean as a deviation from the heterozygote genotypic value. As an example, imagine a one locus two ...
5
votes
1answer
87 views

Can androgen-insensitive genetic-males get pregnant?

According to the linked report, people with androgen insensitivity syndrome appear as male, but have both feminine and masculine outer genitalia. However, I was not able to find out whether their ...
2
votes
1answer
37 views

Where is ATP used in Phosphorylation?

In the section describing the Calvin Cycle, under the subheading "Reduction", my textbook states that: The steps involve utilisation of 2 molecules of ATP for Phosphorylation... I could not get ...
3
votes
1answer
120 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
38 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 ...
5
votes
1answer
40 views

How should species density be calculated for a clumped distribution?

Lets imagine 5 plots of different size are sampled for a target species: ...
2
votes
1answer
62 views

What is this plant on the photos?

Found in Kustaankartano, Helsinki, Finland in June 2015. (for closeup view, copy image URL and open in new window and then zoom in)
5
votes
1answer
127 views

Sequence evolution simulation tool

I'm looking for a tool to simulate sequence evolution given a specific mutation model and birth-death model. I'm aware of tools and packages like INDELible, Seq-Gen and PhyloSim, but they simulate ...

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