3
votes
2answers
256 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
24 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
35 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
75 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
219 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
47 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
261 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
52 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
143 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
29 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
147 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
62 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?
2
votes
1answer
68 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 ...
2
votes
3answers
161 views

Many spermatozoa, but just one ovum

Why do men produce so much spermatozoa, that will get discarded, but women, just ovulum, but it's a good one. Couldn't men produce good spermatozoa as a limited edition? Where is the evolutionary ...
1
vote
1answer
54 views

Does Yerba Mate contain Beta carbolines like harman and norharman?

I know that this is true of (roasted) coffee but haven't been able to find any reliable information about mate in its smoked or steamed state. Thank you.
4
votes
1answer
238 views

RNA isolation from Drosophila head

I need to isolate RNA from Drosophila head. I basically chop the head off and first homogenize it with a homogenizer (similar to this: ...
1
vote
1answer
33 views

Are there any forms of heart failure where cell size decreases?

I think hypertrophy happens in most of the cases. However, I am not sure if hypertrophy always happens. I started to think about wet lungs (pulmonary reason for the left-sided heart failure). Can the ...
0
votes
2answers
40 views

Does fat on our heart come from the fat that we eat?

If we eat fat: Does the fat go into heart, arteries and fat cells. OR Is the fat digested, following which our body creates fat that goes into heart, arteries and fat cells. Which one is right?
0
votes
1answer
30 views

Can systemic venous congestion caused by tumor?

I am thinking, if 1) little compressed superior caval vena and 2) some vein compression by tumor, can cause systemic venous congestion. I think this is only in rare occasions. However, the question ...
1
vote
1answer
46 views

What is ischaemia exactly?

I think it is decreased blood supply to organs and tissues. I also think it is the stopped circulation. However, both ones cannot be right, I think. What is ischaemia exactly?
2
votes
1answer
34 views

What can thrombosis lead to?

I am thinking this question. Thrombosis can result in organisation of thrombus, sepsis thromboembolism, fibrinoid swelling adiposity. I fibrinoid swelling (edema) (4) can occur. Also, I think (3) ...
2
votes
1answer
273 views

Is it impossible for a retrovirus to be lysogenic?

Is it impossible for retroviruses to be lysogenic? In the lysogenic cycle, the viral genetic material is incorporated into the host cell's DNA. Because retroviruses have RNA, it would be impossible ...
1
vote
1answer
51 views

In the lysogenic cycle, does the provirus split from the cell's main genetic material for replication?

In a diagram of the lysogenic cycle sent by my instructor in a video, it shows the provirus splitting from the cell's main DNA when the dormancy period ends and the viral DNA is "activated". Is this ...
3
votes
2answers
191 views

What happen's to a virus's capsid after it injects its genetic material into the host cell?

After a virus (one of the varieties which infects the cell via injection and not endocytosis) injects its genetic material into the host cell, what happens to its protein coat? I would guess that it ...
2
votes
1answer
106 views

Do lysogenic viruses only infect bacteria?

In the video sent by my teacher on viruses, the example he used for lysogenic viruses was a bacteriophage infecting a bacteria. When he was describing how the genetic material was incorporated into ...
2
votes
1answer
80 views

Lytic Viruses — Cell lysis?

So in the video my instructor sent on viruses, he said that for lytic viruses, new viruses manufactured by the host cell could get out of the cell in one of two ways. The new viruses would leave by ...
4
votes
2answers
468 views

In biosynthesis of cysteine and methionine, where does the sulfur come from?

Methionine and Cysteine are the two amino acids containing sulfur. According to wikipedia, cysteine is built from methionine. However, the wikipedia also claims that methionine is synthesized from ...
3
votes
1answer
109 views

How is a stem-cell induced to assimilate a knock-in DNA construct?

While looking at (daylight) color perception I came across a paper by Jeremy Nathans (et al., Proc. Nat. Acad. Sci., vol. 100 no. 20, 2003, full text here) in which he describes the creation of a ...
2
votes
2answers
82 views

Databases for metabolic pathways of human disease

Which databases contain the metabolic pathway of human diseases? I have searched Metacyc and KEGG but didn't find the appropriate metabolic pathway.
0
votes
1answer
98 views

What is the difference between intracardiac and extracardiac reflexes in cardiac regulation?

The primary parameters of heart pumping are strength of contractility (inotropic positive; Frank-Starling relationship) rate of relaxation (lusitropic positive) heart rate (chronotropic positive) ...
1
vote
1answer
202 views

How does a fertilized egg form 23 pairs of chromosomes?

I am always confused about this...so when one cell which has 23 pairs of chromosomes undergoes the two meiotic divisions it produces four cells containing 1 chromatid of every chromosome pair so when ...
4
votes
1answer
33 views

Dyes to bind to double stranded DNA?

Are there any commercially available fluorescent dyes that will bind only to double stranded DNA (not RNA, single stranded DNA etc.) for studying in vitro using confocal microscopy?
2
votes
2answers
358 views

Do recessive alleles really exist?

This question may seem illogical to some, but I seriously have this doubt. I searched google for some proofs but they were extremely complex and I couldn't understand anything. I was just wondering ...
6
votes
1answer
511 views

How much does the distance between a transcription factor binding site and a promoter influence transcription?

Assume we have a synthetic construct with a minimal (inducible) promoter that requires activation for significant transcription to occur. Realistically, how important is the distance between an ...
1
vote
1answer
37 views

Surrogacy Post Fertilization

The wikipedia page on surrogacy highlights two main forms of surrogacy: Traditional Surrogacy and Gestational Surrogacy. Traditional surrogacy inseminates the surrogate mother with sperm, while ...
1
vote
1answer
222 views

X Linked Hardy Weinberg Equilibrium Problem

In a given population under Hardy Weinberg equilibrium, 40.0% of men have hemophilia. What is the probability that a random man and random woman will have a daughter with hemophilia? I think the ...
2
votes
1answer
53 views

Quorum Sensing in Vibrio cholerae

This is a figure summarising the quorum sensing mechanism in Vibrio cholerae. In this video by Bonnie Bassler, she explains how quorum sensing can be targeted to control infections. At 15:09 she ...
2
votes
1answer
1k views

Is urine dirty as soon as it leaves the human body?

Human urine is sterile as long as it is in the human body. But is it dirty after leaving the human body? Could you get sick from it, if you drink it or don't wash your hands, for example?
6
votes
1answer
74 views

Absorption rate of Infrequently eating animals?

Clearly, creatures such as us humans, after vastly increasing the entropy of our food, expel most of the mass that we consume. Some creatures, however, do NOT get the opportunity to eat nearly as ...
18
votes
4answers
8k views

Can humans eat grass?

Can a human eat grass and digest it? Could it be possible to use it as food just like other plants such as wheat or beans?
0
votes
1answer
79 views

Systems Biology of triacylglycerol (TAG) synthesis in Jatropha

I need the genetic regulatory network of TAG synthesis (Kennedy pathway) of Jatropha plant?? Or is there any way to convert metabolic pathway into genetic regulatory network?
1
vote
1answer
136 views

Raising two legs together while lying on bed

Let's do some exercise(duh!) Ok so lie on the bed. Lift your left leg. Put it down. Lift your right leg.Put it down. Easy? Now lift your left leg and without putting it down, lift your right leg. ...
3
votes
2answers
106 views

Are viruses self-propelled?

So obviously, viruses are nonliving. But when my teacher was teaching viruses in the video (we're doing "flip" learning this semester), the way he described it, it seemed like the viruses responded to ...
0
votes
1answer
116 views

what these suffixes mean,-coel,-blast,-cyst? [closed]

in the connective tissue (Bones) we have 3 types osteoblast, osteocoel,osteocyst what are they and why they differ.
4
votes
2answers
150 views

What is the evolutionary purpose of the topology of the human ear?

What is the evolutionary purpose of the topology of human ears? I understand why the ears may have a funnel-like shape but if the various "hills and valleys" do not amplify incoming sound, what ...
0
votes
1answer
51 views

Do's and Don't's of Undergraduate Research? [closed]

I was fortunate enough to get a position as a researcher for the Mayo Clinic's SURF Program this year. My PI's lab focus is on the the immune system's role in CNS axonal and neuronal injury, ...
4
votes
2answers
2k views

No bands show up in gel electrophoresis, not even marker

I haven't seen any gel lanes in neither my PCR samples nor the marker itself when photographing them. This is not my first time performing 1.2% agarose gel electrophoresis. I see gel lanes when I ...
4
votes
2answers
156 views

Evolution in fruits

So, I saw a video on YouTube that says the banana we eat today is not what a banana looked like years ago. Since the banana has been genetically modified over the years, does that qualify as ...
2
votes
1answer
499 views

Why do cells vary in shape and function when they have the same genome and the same organelles?

Why do cells vary in shape and function when they have the same genome and the same organelles. For example: why do all cells have nuclei but red blood cell's don't; why can't the cells of a eye ...

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