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
121 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
54 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
115 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
203 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
130 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
88 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
968 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
817 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
147 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
341 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
26 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
530 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: ...
0
votes
1answer
21 views

Do animals follow tactics?

Are animals able to plan hunts, give tasks if they do it in groups and fulfil it adapted to the current situation? Do they use unique tactics for special circumstances (e.g. based on experiences) or ...
0
votes
1answer
63 views

Resources for interesting facts about biology [closed]

Are there resources for interesting or fun facts about biology, for example: fastest animal/bird/insect largest organ in human body largest virus largest genome largest de novo synthesized genome ...
2
votes
1answer
92 views

Lethality of a stab wound to the back

How deadly is a stab in the back? Video games, movies, and other fiction would have us believe that a backstab against a foe with a modestly-sized blade leads to immediate and certain death, having a ...
3
votes
2answers
449 views

What is the fastest marine mammal?

When I did a research, most of the sources say that orca is one of the fastest. But I could not find a source that says it is actually the fastest. Some sources say that Dall's porpoises rival orcas ...
0
votes
1answer
38 views

What are these white areas of coronary thrombosis?

Please, see the picture where the areas (1,2,3) look little yellow: I think these areas are fat, platelets and/or air. I think 3 is fat/platelets while 1 is air/platelets. There also exists white ...
1
vote
1answer
37 views

Drosophila Crosses

I have 2 transgenic lines of Drosophila. I would like to cross them and get both transgene in the same fly. To start this cross, does it matter which fly is female or male? Or as long as the female is ...
1
vote
2answers
89 views

Why only water in liquid form is essential to live?

My question is:- Only liquid water supports almost every living organism's metabolism, neither the vapour nor the condensed form of water does so. What is the chemical & the biological reason ...
4
votes
1answer
297 views

What is the minimum length required for a circular DNA ligation?

What is the minimum length of a DNA molecule for the ends to come in close enough contact that they can ligate. Assume there are free divalent cations in solution. Does anyone have any idea?
3
votes
0answers
50 views

What makes the amide bond the lowest energy pathway? [closed]

I've reading about proteomics and how it can be used with mass spectrometry to sequence digested peptides. Reading this paper the author states (in box 2): peptide fragmentation induced by ...
3
votes
1answer
374 views

From a purely biological perspective, how does an optimal human diet look? [closed]

There is hardly any subject as contested in the media as what humans should eat. Usually, such discussions are devoid of actual scientific reasoning, though they all claim to be backed by scientific ...
4
votes
1answer
59 views

Is it possible to elicit transient gene silencing by using virus induced gene silencing (VIGS) in plants?

I am looking for a molecular tech' which could result in transient gene silencing in plants. The objective is to not make transgenic plant, but to use these tech' to silence a gene of interest for a ...
4
votes
1answer
924 views

How do wild animals get rabies?

I can see the chain of spreading disease: Humans usually get rabies from domestic animals, those usually get it from wild animals, wild animals in their turn get from the other wild animals and here ...
2
votes
1answer
33 views

Can animals absorb atmospheric sulfur?

This is a follow up to this previous question: In biosynthesis of cysteine and methionine, where does the sulfur come from? Can animals use gaesous H2S in the atmosphere, say for instance from a ...
1
vote
1answer
195 views

Bacterial Conjugation/Horizontal Gene Transfer — how does the plasmid exchange work?

So according to a PPT I'm reading, bacterial conjugation works by the two bacteria joining pili and exchanging plasmids. So how exactly do the plasmids get across the gap? If I understand this ...
8
votes
2answers
2k views

Why do I need a flu shot every year, while many other vaccinations last years or even a lifetime?

Is it a viral vs. bacterial thing? Is there just more variety among types of flu than other diseases, so that this year's vaccines don't cover next year's flu?
-1
votes
1answer
101 views

Organs lifespan out of the body [closed]

What organ can be conserved outside of the body for the longest time and still function when reimplanted?
3
votes
1answer
87 views

Evolution from Mating types to different sexes

Imagine a lineage of multicellular organisms that had mating types and evolved their mating types into sexes. What are the possible mechanisms that might have brought this lineage to evolve sexes from ...

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