4
votes
1answer
246 views

Sexual Differentiation in Monoecious plants with unisexual flowers

In monoecious plants having unisexual flowers (eg Zea Mays, Ricinus Communis etc), there must be some mechanism as to produce two sexually distinct flowers from the same genotype. Since both the type ...
2
votes
1answer
135 views

What is this plant?

I really like this plant--I'm just wondering what its name is (perhaps genus+species). I think this plant grows in the tropical rainforest in Malaysia. Any suggestions? Thanks!
0
votes
1answer
24 views

Why violets die in closed space?

I'm going to engage into making florariums (a garden in the bottle). I've heard, that violets die in closed space. Do anyone have an idea, what is the reason for that? Lack of oxygen or CO2 or ...
2
votes
2answers
126 views

Can a fungus become resistant to a chemical such as Potassium Permanganate?

A friend used potassium permanganate solution to treat tinea on the hands/feet but after some initial success, the tinea seems to be making a comeback. Could the fungus develop resistance to potassium ...
3
votes
1answer
61 views

How can I re-format my DNA motifs' position weight matrices?

I am working with a set of DNA motifs that are predicted as potential regulatory motifs (e.g. transcription factor binding sites). The motifs belong to several species, and I wanted to cluster these ...
2
votes
3answers
91 views

Real-time PCR result interpretation

I performed real-time PCR and I was looking for expression fold changes for 2 genes and I had two sample pools, one treated and the other not treated (for each gene). The problem is that my ...
0
votes
1answer
202 views

Pathogenesis of Chronic Venous Congestion in Lungs?

I am thinking how CVC in lungs lead to the left-sided heart failure.
3
votes
1answer
176 views

What insect is this..?

Can anyone tell me what kind of insect (if it is one) is this...!! Or is it the pupa of some insect? Well I don't think that the whole big thing is the insect itself, it appears to be just a kind of ...
1
vote
1answer
88 views

What is the pathogenuc mechanism of brown pigment lipofuscin in muscle atrophy?

I think it is autophagy. Lysosomal degradation. Autophagocytosis. Example of the brown pigment (lipofuscin) here: I am not sure if autophagy is the right answer to the "pathogenic" mechanism of ...
0
votes
1answer
53 views

Pathogenesis of chronic venous congestion in skin?

I think CVC cannot lead to heart failure primarily. So let's think its pathogenesis in skin now only. I think the pathogenesis is like this dilation of veins and capillaries due to impaired venous ...
3
votes
4answers
79 views

Can systemic intravascular thrombosis cause brain infarction?

I wonder if the thrombus can pass through the brain-blood barrier because I think small molecules like O2, CO2 and ethanol can pass it. Probably, in some diseases where the permeability of the barrier ...
-1
votes
1answer
86 views

Dimensional analysis Question

So I'm new to the dimensional analysis world and I'm little confused and the answers I'm getting are not convincing :( if the concentration of hemoglobin in a 5ml sample of blood is 34 g/dL. and red ...
0
votes
1answer
109 views

How does DNA mess up

When there is an error in copying DNA (a mutation), what exactly goes wrong? If G goes with C and A goes with T, I don't see how that part can mess up. Is the idea that when the double helix is ...
3
votes
1answer
81 views

Hela live cell confocal laser scanning - reccommendations for good fluorophore that will show good movement

I've been doing a lot of live cell imaging lately mostly using hela cells expressing some EYFP based chimeric proteins. I'm building a video library for an art student here at the university who is ...
2
votes
2answers
352 views

How much of your stock solution should you take to make the 1000 cells/mL mixture? [closed]

You need a solution containing 1000 buccal cells/mL. You count that you have 125 buccal cells in 50uL, from a total solution of 8 mL. How much of your stock solution should you take to make the 1000 ...
1
vote
1answer
32 views

Which inflammatory response with Cytomegalovirus infection?

I am thinking about inflammation process with Cytomegalovirus infection. I first thought it is about chronic inflammation, but then changed my mind because of virus infection. I think cytokines must ...
2
votes
1answer
34 views

Neuroscience: zapping an axon connected to thermoreceptor

Let’s say an experimenter has an electrode that can give a shock to a single axon. She takes that electrode and zaps an axon connected to thermoreceptors in the hand of her subject. I) What would the ...
3
votes
1answer
56 views

spinal cord lesion and result in somatic sensation

Jimbo suffers a lesion to the entire right half of the spinal cord at the T6 level. A few weeks after his injury, his doctor tests his right and left legs for somatic sensation and tone. fill out her ...
3
votes
1answer
49 views

What stops telomerase?

The telomerase is an enzyme that adds telomeres. What stops the telomerase from adding too many telomere sequences ? What's the regulating mechanism ?
1
vote
1answer
21 views

2 types of telomerases?

As telomerase works by adding new nucleotides complementary to the RNA it contains, it cannot work for the complementary strand. Say telomerase X has RNA complementary to the 5' to 3' strand it ...
4
votes
1answer
34 views

Telomerase in tetrahymena

In this amazing video, at 26:03 we see this image We now know that the telomerase contains a sequence complementary to the telomere sequence and so is able to do what it is capable of doing in this ...
1
vote
2answers
120 views

Conserved proteins are non immunogenic

I read that proteins that have been highly conserved are non-immunogenic. Why is it so ? What is the special thing that makes it non immunogenic(antibodies against them are hard to make) ?
2
votes
1answer
53 views

Meaning of the word Oleracea

What does "oleracea", as appears in numerous plant species (scientific) names, mean? Examples: Euterpa oleracea, Brassica oleracea, Portulaca oleracea, Acmella oleracea, Spilanthes oleracea.
1
vote
0answers
62 views

College Bio Research: Bacteria found on computer keyboards. [closed]

I am a college students brainstorming ideas on different topics that may be appropriate for on-campus research. What I came up with and I would like to give it a try is analyze the different types of ...
4
votes
1answer
142 views

How to calculate the effective population size ($N_e$) with overlapping generations?

From this Source: If generations are overlapping, then the effective population size $N_e$ does not equal the population size $N$. I know mathematical formulations in order to find the effective ...
2
votes
1answer
67 views

Effective population size when the population sizes varies from season to season

Let's think of a species which has four generations per year and which population size changes from season to season so that the population size is 100 in summer, 200 in spring, 50 in autumn and 20 in ...
-2
votes
1answer
50 views

Which chemical and hormonal effects on heart are by metabolites? [closed]

I am thinking which hormonal and chemical effects from: catecholamines thyroxin corticosteroids sex hormones prostaglandins Ca2+ Na+ K+ can be be regarded as metabolites i.e. intermediates or ...
5
votes
2answers
114 views

Linkage disequilibrium with multiple alleles and loci

Linkage disequilibrium $\left(D\right)$ for two bi-allelic loci is defined as: $$D=X_{11}X_{22} - X_{12}X_{21}$$ where $X_{11},\ X_{12},\ X_{21},\ X_{22}$ are the frequencies of the haplotypes ...
7
votes
1answer
92 views

Selection on linked loci in a diploid population

Let’s consider two linked loci $A$ and $B$ that are both bi-allelic. In consequence, we have four different possible haplotypes $A_1B_1$, $A_1B_2$, $A_2B_1$, $A_2B_2$, which frequencies are $X_1$, ...
1
vote
1answer
201 views

Does the lung absorb organic food?

Imagine you swallow something up and not everything gets out of the windpipe (this is possible right?). Would it be possible for the lung to handle with the rest implying that it is organic? Would it ...
1
vote
1answer
129 views

Why are low throughput methods more trustable for protein interaction?

I read that protein interactions found using high throughput methods are less trustable than those found using low throughput methods. For example, searching for interaction of BRCA2 on BioGRID, I ...
5
votes
1answer
103 views

enzymes that stabilize DNA loops

As a follow-up of a previous question, I would like to know what enzymes or protein complexes have been used to manipulate DNA samples into stabilizing DNA loops. I have read that cohesin is one of ...
2
votes
1answer
5k views

Why can't ciliary muscles in the human eye relax like other muscles?

I had laser eye surgery a decade ago, but in recent years my eyesight has become significantly myopic. I consulted an ophthalmologist to see if this was eye strain because I work at computers a lot, ...
2
votes
1answer
63 views

Would expression of GroEL and GroES in erythrocytes be a potentially effective therapy for sickle cell disease?

Would expression of GroEL and GroES in erythrocytes be a potentially effective therapeutic strategy for sickle cell disease? Why or why not?
3
votes
1answer
87 views

How do Kangaroo mothers deliver the correct kind of milk to the correct joey?

Mother kangaroos are able to rear multiple joeys (young kangaroos) at different stages of development at the same time. According to Wikipedia, "the mother is able to produce two different kinds of ...
1
vote
1answer
56 views

Omics integration questions [closed]

Let's say that I have a population of Mus musculus in the lab. I divide it in a control group and a test group. The test group is constantly subjected to a stress (example: elevated UV radiation). ...
4
votes
1answer
958 views

Examples of animals with different number of chromosomes that can interbreed?

When I was first started to write this question, I wanted to know how species evolve to have a different chromosomal arrangement, such as having two pairs of chromosomes instead of one? However, I ...
4
votes
2answers
816 views

If DNA has a half life of about 500 years, how can old seeds be planted?

According to this article, DNA has a half life of 512 years Wikipedia claims that there are seeds planted as old as 31000 years Doing the basic math $100 / (2^{30000/512})$ we get that only about ...
2
votes
1answer
145 views

Evolution of Homo Erectus to Homo Sapiens

I just read an article on Wikipedia and noticed that some similarities between Homo Erectus and Homo Sapiens in the "Comparative table of Homo species". My question is; Is it possible to say that ...
1
vote
1answer
338 views

circularizing DNA molecules?

I have been reading about next-generation sequencing technologies that can sequence long reads. Even though the origin of my question is sequencing technologies, the question I am asking is about the ...
3
votes
3answers
92 views

Publicly available genotype data?

I am a statistician and I'd like to test my new method on biological data. For this I am looking for genotype data for a number of individuals. That is, I am looking for something like this: ...
2
votes
3answers
2k views

How do a viruses or bacteria survive outside the body long enough to spread?

Say I cough on my table, then someone else touches it and picks up something I've got... how is it that these things can live outside the body, how long can they manage it, and how long is generally ...
2
votes
1answer
67 views

How much solar energy required to compensate food?

Just curious, how much solar energy can power an (herbivore) animal? Specifically, is it enough sunlight on Mercury (4 to 10 times brighter than on Earth) to "feed" a zebra? Will it be sufficient at ...
1
vote
1answer
64 views

Is it easier to burn a calorie of fat or a calorie of a carbohydrate?

Say someone eats 100 calories of chocolate vs. 100 calories of carrots. Something tells me that eating the chocolate will lead to you generating more fat. Will it? Is it harder to burn the calories ...
6
votes
1answer
84 views

How to determine whether a newly discovered dinosaur is not a young one and not an entirely different species?

Every once in a while, there is an official announce that a new species has been discovered. For example, paleontologists have recently discovered a dinosaur they named Nanuqsaurus hoglundi, which ...
0
votes
1answer
25 views

To characterise diameter of capillaries in organs

I know that there exist Continuous capillaries (skeletal muscle, adipose tissue, connective tissue, pulmonary circulation), Fenestrated capillaries (small intestine, renal glomerulus, exocrine ...
2
votes
1answer
511 views

What kind of a microscope do I need to see cell organelles?

I would like to study cells and looking for a microscope that would allow me to see: groups of cells individual cell cells organelles I would like to target insects and mammal tissue. I would be ...
1
vote
1answer
177 views

Real time PCR parameter CT

When puting a real time PCR, parameter CT, which means threshold cycle, is used. What does it mean really? according to wikipedia "The number of cycles at which the fluorescence exceeds the threshold ...
0
votes
1answer
43 views

What is the quality rate of intrinsic autoregulation in the heart?

Autoregulation is the maintenance of constant blood flow to an organ in spite of fluctuations in Blood pressure. It involves the relaxation of myocardium and contraction. It is local. I know that ...
1
vote
1answer
141 views

Is Natural Selection like a Copy Editor?

I am stuck on a Homework Question. It says: Evaluate the following statement: “Natural selection works like a copy editor; it works only with what is already present in a population.” (Note: ...

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