2
votes
2answers
192 views

Why can't this be 1st meiotic division non-disjunction as well?

The child has gotten 2 "sick" chromosomes from his dad and 1 healthy from his mom, leaving it with trisomy 13. I can see how this can happen in the second meiotic division of the father but I can ...
1
vote
1answer
72 views

Is dinoprost PGF2-alpha or PGE2?

In many places it says PGF2-alpha. Now, I am thinking PGE2 is a substype of PGF2-alpha. However, I am not sure. Is dinoprost PGE2?
1
vote
1answer
129 views

Are there any culinary fruits that are not botanically fruits or accessory fruits? [closed]

Many culinary vegetables are botanically fruits. For example, the tomato, bittergourd and the cucumber are generally considered culinary vegetables, but they are botanically considered fruits. Does ...
3
votes
3answers
57 views

Doxorubicin's intercalant and topoisomerase inhibition in leukemia?

I am thinking the role of doxorubicin's pathways in cancers such as leukemia and lymphoma: topoisomerase inhibitor and inhibit DNA activity intercalant - intercalant DNA bases and inhibit DNA ...
1
vote
0answers
17 views

Imidazoline receptor agonist in clonidine?

I am thinking which pathway is more important in hypertension, ADHD and withdrawal of clonidine: alpha-2 agonist imidazoline receptor agonist (maybe) Alpha-2 is the classical one. Pubchem starts ...
21
votes
3answers
2k views

120-year-old gene regulation problem independently solved by a computer. How?

My Background: I'm a mathematics graduate student with a physics background. I have a very little biology knowledge and a little knowledge of machine learning and statistics. Topic: I recently ...
4
votes
1answer
290 views

How can omnivores be in more than one trophic level?

I'm learning about the ecosystem and its relation to organisms, So organisms in a food chain can be put from producers to tertiary organisms. I just don't get the part where an organism can be labeled ...
0
votes
2answers
100 views

Chromosomal translocation notation

A reciprocal translocation is denoted for example: t(4;12)(q32;q24) indicating that q32 on chromosome 4 being swapped with q24 on chromosome 12 if I understand this correctly. My question is: How do ...
0
votes
1answer
45 views

X-recessive disorders and genetic markers

Please observe the following pedigree of a family with a x-recessive disease (bleeder disease). The A's are genetic markers so close to the disease gene that recombination is negligible. I ...
6
votes
1answer
107 views

Viruses selected by evolution

First let me apologize in advance for I know almost nothing about biology. I had a conversation today with a family member who is a bio-computer-scientist and he talked to me about what his colleagues ...
1
vote
1answer
30 views

Is there a way to examine amount of red/white muscle fibers without biopsy?

I want to conduct some research on red and white muscle fibers, why do some people tire during certain movements while others do not. Obviously I can't get a biopsy on the subjects so I wanted to hear ...
-1
votes
1answer
107 views

Pedigree problem and type of inheritance [closed]

Please observe the following pedigree and come up with a conclusion as to which type of inheritance is most likely Now it should be obvious that it's either autosomal dominant or autosomal ...
1
vote
1answer
86 views

Plasmid gene knockout

How do delete a single gene encoded in an operon on a plasmid using E. coli? Could you use the same principle as when knocking out a gene from the bacterial chromosome which is e.g. suicide vector-...
3
votes
1answer
260 views

Are there examples of now-living species where one is descended from the other?

I'm not a biology person so please forgive me if this question is formulated badly :) I'm curious. Are there any species that has an ancestor species that is still alive today?
0
votes
1answer
18 views

What does this sentence about angina mean?

I do not understand this sentence Angina can be treated ambulatory (in out-patient) in stable angina. I think ambulatory refers to ambulatory ECG monitoring. So I understand this that you can ...
4
votes
1answer
3k views

Which are mobile and immobile elements in plants?

I am confused with this element or nutrient classification in the plants, since some authors set elements like $\ce{S}$ and $\ce{Ni}$ as mobile and other as immobile elements (Citation 1, 2, 3, 4, 5). ...
3
votes
1answer
85 views

Walk me through microsatellite markers and PCR

Three polymorph microsatellite markers are used to try and narrow down the location of a disease locus, with the use of PCR with 2 flanks on each side of the actual polymorphic area. The PCR product ...
3
votes
1answer
47 views

Gene frequency problem

1/330 of white people in south Africa have a disease called Porphyri. What is the frequency of the gene if it is inherited autosomal recessive? This one I understand. The genotype frequency is $q^2 =...
3
votes
2answers
426 views

How do roots obtain nutrition?

I have a city garden (see picture below) and yesterday I was nurturing it and I pulled up a small plant. I saw its root system and laid it in the sun to dry a bit and then scraped of the rest of the ...
2
votes
1answer
113 views

Which tree's root can grow the longest?

In a recent TV documentary it was said that a particular tree root could grow miles long. However, I forgot the name of the tree and I don't remember the name of the TV program as well. I searched ...
6
votes
1answer
53 views

Independent contrasts with non-homologous traits

I have morphometric measurements for a trait across various animal taxa, and would like to study the relationship between the size of this trait, and the animals' body size. In theory, I can account ...
1
vote
1answer
50 views

How is magnet based bead capture used for indexing-first ChIP-seq?

The context for this question can be found in this paper by Lara-Astiaso et al. Here, to study H3K4 trimethylation in various cell types, they sort cells sonicate chromatin immobilize chromatin on ...
7
votes
3answers
262 views

Why does the human brain not overfit when training at some task?

One of the problems that occur during (artificial) neural network training is called overfitting. The error on the training set is driven to a very small value, but when new data is presented to the ...
5
votes
2answers
410 views

Transformation of E.coli cells

As a team of undergraduate researchers we are looking to transform two genes of interest into our competent E.coli cells. Both of these genes are in separate plasmids and we would like to put them ...
2
votes
1answer
108 views

Is the golden ratio of anatomic measurements universally beneficial for sexual reproduction? [closed]

It is often claimed, in popular media, that the golden ratio (Fibonacci series) in for example some face measurements is aesthetically (and hence reproductively) attractive with respect to the humans. ...
3
votes
1answer
74 views

Write the haplotypes of the family

I'm doing old exam assignments to prepare for my finals on Monday and I've stumbled on one assignment that I'm not sure how to tackle. A family with 2 children is examined for cataracts using PCR ...
1
vote
1answer
69 views

Dynamic mutation and huntington's

I read that Huntington's is a disorder caused by dynamic mutations in the DNA, which means that a triplet sequence of DNA changes from generation to generation. Say we have the sequence ATGATGATGATG. ...
5
votes
1answer
95 views

How are behaviors genetically coded in animals?

I am curious as to how complex behavior is passed down genetically? For example, how is the building of a web genetically coded in a spider? And how is the complex behavior of constricting prey coded ...
4
votes
2answers
53 views

Flower identification (England, late May)

I took this photo near Stratford upon Avon by the side of a road. Can anyone identify this flower?
1
vote
0answers
67 views

Primer heterodimer problem

I design my primers in Primer3PLUS and analyze them in Oligoanalyzer3.1, A big problem that I have this is that I got very nice output in NCBI-Primer BLAST for their specificity but a very negative ΔG ...
3
votes
1answer
400 views

What is the name of this flower? The photo was taken in the Okanagan Valley, British Columbia

This little flower was growing on dry ranchland in Kelowna, it flowered in April:
6
votes
1answer
361 views

Can someone identify this plant?

Can someone identify this plant? It was growing under my 2 year old's climbing wall / play house thing. I live in West Virginia, USA and it's currently June 3rd (if that helps from a climate ...
0
votes
1answer
253 views

Are Humans Considered Keystone species? [closed]

Do humans have a huge impact on the ecosystem ? is it possible for other animals to live without us ?
5
votes
1answer
174 views

Do humans have skin cells that trigger oxytocin release in the brain?

I was reading an article by Montgomery on the therapeutic effect of pets (Boston Globe, January 12, 2015), and I found this quote: All animals appear to have cells directly under the skin that ...
4
votes
4answers
3k views

What is the difference between a spore and a cyst?

Last year I read a course in biology. During that course I learnt that Protozoa like Lamblia intestinalis or Entamoeba hystolitica form cysts in unfavourable conditions. This year I read a course in ...
0
votes
0answers
22 views

Help with STRING database

How can I generate a graph on the STRING web server for physical interacting proteins only? I know we could extract the data and use Cytoscape to create a graph, but I would prefer to have a graph ...
4
votes
1answer
106 views

How can electric fields inhibit tumor growth?

In MIT's Technology review it is explained that electric fields can cause dividing cancer cells to explode, while these fields have no significant impact on non-dividing tissues. The original research ...
1
vote
1answer
35 views

What's a segmented copy number profile

I am studying copy-number variation. I am reading C. H. Mermel, S. E. Schumacher, B. Hill, M. L. Meyerson, R. Beroukhim, and G. Getz, “GISTIC2.0 facilitates sensitive and confident localization ...
1
vote
1answer
1k views

Background correction when reading ELISA with TMB substrate

I'm doing some ELISA development, and I'd like some justification/best practices for background correction. I'm using a horseradish-peroxidase (HRP) detection system along with a TMB substrate and an ...
5
votes
3answers
273 views

What is a genetic marker?

In DNA sequencing and analysis, what is a genetic marker? I've heard that microsatellites are genetic markers? Those are repetitive strands of bases such as GCAGCAGCAGCA etc. Why are they markers and ...
2
votes
0answers
56 views

Differing number of “things” in mammals [closed]

I'm not a biology expert, but I have often wondered about the following facts of life: All mammals have precisely 5 fingers on each of our 4 extremities. Granted, some may not be seen, but the bone ...
4
votes
1answer
383 views

Measuring body size in flies/insects

"Mesothorax length (the distance from the tip of the scutellum to the most anterior part of the mesothorax)" From Bergland et al 2008. Would that be this distance (green line)? If not, how ...
2
votes
1answer
122 views

From a computer science perspective, how is DNA compared for various purposes?

I am very interested in privacy preserving technolgies, such as Microsoft PINQ and would like to see if this is applicable to DNA comparison. Given that I don't have a background in biology, I ...
8
votes
4answers
105 views

Are there constraints on where intron/exon boundaries occur with respect to the triplet codons of the reading frame?

I did a quick search (here and elsewhere) and couldn't find anything on this subject. If all introns in a given primary transcript were spliced out in the same way, then this wouldn't matter. But ...
0
votes
1answer
21 views

Will tagging a protease with HlyA for secretion inactivate the protease?

We are looking to secrete the protease proline iminopeptidase by attaching the secretion signal HlyA to the protease in a gene circuit. Since the natural HlyA secretion sequence in Escherichia coli ...
2
votes
2answers
224 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 ...
5
votes
1answer
65 views

Are there eukaryotes with fully working mitochondria but without mitochondrial genes?

Are there eukaryotic organisms with fully working mitochondria that do not have genes in the mitochondria? By fully working, I mean ones which can carry out oxidative phosphorylation, unlike reduced ...
3
votes
1answer
506 views

What is the distinction between the terms detrivores, decomposers, saprotrophs and saprozoic organisms?

All of them feed on dead and decaying matter (detritus). Detrivores and decomposers are distinct, as it says on Wikipedia, in the fact detrivores consume macroscopic clumps of detritus while ...
1
vote
1answer
537 views

Why is Electrical Cardioversion contraindicated in AF and Digitalis Poisoning?

I am thinking why electrical cardioversion is contraindicated in atrial fibrillation with digitalis toxicity/poisoning. Cardiac digitalis is also called digoxin and cardiac glycoside. It is ...
6
votes
2answers
56 views

Why do epithelial cells arrest in response to serum?

Primary epithelial cells, for example human mammary epithelium, fail to proliferate (arrest) in serum-containing medium. Therefore, a common growth medium for epithelium contains pituitary extract ...

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