5
votes
0answers
197 views

Genetic expression in interspecific hybrids

Referring to interspecific hybrids, I have the following two questions:- Quoting from wikipedia:- The offspring of an interspecific cross are very often sterile; thus, hybrid sterility ...
3
votes
1answer
20 views

Microalgae without cell walls?

Most microalgae have rigid cell walls. Dunaliella Salina is a pretty famous example of an algae with no cell wall, but just a plasma membrane. Are there any other microalgae without a cell wall?. I ...
5
votes
3answers
42 views

What does it mean for a hormone to be “active”

In my textbook it is stated that the T3 hormone produced at the thyroid gland is 3-5 times more biologically active than T4. How is being active defined and how can this effect be measured?
0
votes
1answer
95 views

If ALL the melanin in a person was pheomelanin [closed]

If ALL the melanin in a person was pheomelanin... What would change about their appearance and what would the health effects be from such a change?
2
votes
1answer
34 views

GWAS: why is replication in another cohort so crucial?

Almost all the landmark GWAS (Genome-Wide Association Studies) reviews agree that, for a GWAS finding to be valid, it needs to be replicated in an independent cohort. What exactly is the rationale ...
7
votes
2answers
3k views

How does HCl not burn our stomach?

How does the digestive acid (HCl) not burn the surrounding skin of our stomach? It digests the majority of raw food we eat but how does it stay safely in our stomach? Also, how does the stomach ...
3
votes
1answer
24 views

Forensic genetics- why is mtDNA comparison sometimes better than nDNA comparison?

Why is (in forensic genetics) in some cases more appropriate comparison of nuclear DNA but in some other cases comparison of mitochondrial DNA? Is it because geneticists are sometimes unable to find ...
0
votes
0answers
19 views

Genetic Relationship Matrix

The classical definition of the Genetic Matrix G = ZZ'/2p(1-p) where Z = M - P where P = 2(p-0.5) I don't have a background in biology but understand Maths and ...
5
votes
1answer
31 views

Are prosauropods ancestors of all sauropods?

My daughter, while reading a book about dinosaurs, asked me if prosauropods are ancestors of all sauropods. Are they? From the name ("pro-sauropods"), I guess that they are, but am I right?
6
votes
2answers
103 views

What is the purpose of using two layers of gel in SDS- PAGE?

I just made a SDS-PAGE with a top layer of stacking gel and a bottom layer of separating gel with different pH values of 0.5M Tris-HCl. The stacking was 6.8 and the separating gel was 8.8. What about ...
0
votes
0answers
11 views

When are carbon acquisition transporters up-regulated? [on hold]

When are carbon transporters up-regulated in bacteria? Depends on the internal/external nutrient concentrations ratios?
20
votes
5answers
4k views

Do humans have enough biological differences to be grouped into races or subspecies?

After my online research on the subject, I learnt that, biologically speaking, many scientists believe that there is no such thing as a race. Homo sapiens as a species is only 200,000 years old, which ...
0
votes
0answers
21 views

Bacterial metabolism during growth phases [closed]

I would like to know what are the main metabolic differences between the bacterial growth phases. References are appreciated. Thanks!
3
votes
2answers
12 views

What is correct MVM vs. MMV?

I'm writing up a report and I see conflicts everywhere on the internet. Should it be Murine Minute Virus (MMV) or Minute Virus of Mice (MVM). The followup question is does it really matter.
-1
votes
0answers
12 views

pI and pH relation in electrophoresis of proteins [closed]

In a electrophoresis of proteins with a pH of 8,6; proteins which migrate have a pI lower or higher than pH?
6
votes
1answer
209 views

Why does the membrane of a neuron not stay at its depolarized state?

When an action potential is transmitted along the axon, the membrane reaches its depolarized state by opening Na+ channels. Both K+ (potassium) and Na+ (sodium) are now on both sides with close to ...
-1
votes
0answers
28 views

Experiment using nocadazole [on hold]

Nocadazole is a compound known to inhibit microtubule polymerisation and is widely used in laboratory, among other to synchronize cells. I am designing an experimental set up in which I want to treat ...
2
votes
1answer
81 views

Who are these biologists?

I know the third one in the front row is James Watson. Does anyone recognize the others? Thanks!
16
votes
2answers
3k views

How many organisms have ever lived on Earth?

I've looked for some information on this, but couldn't find anything useful. Has there been any noteworthy attempt to estimate the sum amount of individuals of all species that have ever lived on ...
7
votes
2answers
198 views

Could cancer be in itself a evolutionary process?

Could cancer be in itself a evolutionary process? Maybe in some way could it be a process of variation? Or would this idea be completely without support, if so, why? I don't mean that each case ...
6
votes
2answers
87 views

What is this bug?

I recorded a video of this bug: https://youtu.be/0eoWfHLEo7A I counted 8 legs, the front legs are a little curved. The drawing on the flat back is dark and looks like the image of Jesus with some ...
6
votes
1answer
51 views

Why is it harder to sequence plant genomes than animal genomes?

Plants seem to be less complex organisms than animals, but despite that there are less plant genomes sequenced. Is that because plant genomes are more complex, for example in terms of regulatory ...
2
votes
1answer
26 views

Is there any alternative to cryopreserve cell lines without -80 freezer?

My university's -80 freezer just broke down and the repair will take 4 months according to the vendor. Is there any other way to preserve cells? Maintaining lot of flasks until the freezer is repaired ...
4
votes
1answer
27 views

Does hypothalamus regulate posterior pituitary gland?

We have the hypothalamus-anterior pituitary-endocrine axis, but is there a similar chain of command for posterior pituitary gland such that oxycotin and vasopressin are regulated by some tropic ...
6
votes
2answers
60 views

What is the mechanism behind plants losing their leaves? [duplicate]

Do plants that lose their leaves (i.e., deciduous plants) do so because of external conditions (e.g., drought, cold), or because of an internal process? Another way of looking at it: if you take a ...
4
votes
3answers
13k views

What type of cell do you start with in Meiosis?

Okay, I was learning about mitosis and meiosis in school and had a question. I know in Mitosis you first start off with a Diploid (2N) cell and then end up with two ...
10
votes
3answers
419 views

How many cells does the smallest animal have?

Note: question rewritten to prevent misunderstanding and make it more answerable I know that some small animals like C. elegans display surprising sophistication with a very small number of cells. ...
6
votes
1answer
66 views

“Enhancers” of enhancers?

I am looking for examples (if any) of genomic regions which regulates the activity of enhancers, either augmenting or reducing it. Essentially some kind of enhancers (or repressors) of enhancers to ...
-1
votes
2answers
52 views

Hopeful Monsters in Plants? [closed]

Does anyone know of any research/examples on Hopeful Monsters in Plants? I define Hopeful Monsters as organisms of a species that have macroevolutions to prompt new speciations. These ...
4
votes
0answers
37 views

SDS Laemmli Gel that did not solidify

In my lab class this week my partner and I were making a SDS-PAGE Laemmli Gel. We made the resolving gel solution which was made of 30% Acrylamide, DI water, 1.5 M Tris-HCL pH8.8, and 20% SDS. We ...
15
votes
6answers
2k views

Human evolution: Where *exactly* did the first human come from, whose parents were not?

Layman here. So I have never really quite understood this facet of human evolution, (or any other for that matter), in that, I understand the evolutionary process, but I get lost on the 'border' ...
3
votes
1answer
37 views

Why are pharmacology studies so experimental?

I am a medicine student, and as far as I see from our pharmacology lectures, pharmacologists work almost completely experimental. Quite typically they take a substance (e.g., from nature), they add, ...
4
votes
1answer
90 views

Length of sleep time

Why do we wake up after 6-8 hours of sleep ? Why don't we sleep for lets say 20-30 hours ? What mechanism is it that controls when to wake us up and how does it determine the moment that we should ...
4
votes
2answers
459 views

Why do men have a higher hematocrit (red blood cell count) than women?

The hematocrit, also known as packed cell volume (PCV) or erythrocyte volume fraction (EVF), is the volume percentage (%) of red blood cells in blood. It is normally 45% for men and 40% for women. ...
3
votes
1answer
19 views

What is the difference between “physical interaction” and “genetic interaction”?

I searched sac1 in uniprot to know more about this gene. in interaction I selected this link and there I see that this gene has some "physical interactions" and "genetic interactions". I am wondering ...
2
votes
2answers
104 views

Why are there no trees in Texas?

In Texas, there is lot of grassland and many cotton fields, which need a great deal of water. However, I have not seen any forests or areas with many trees. Why are there no forests or heavily-treed ...
2
votes
1answer
32 views

Can we knock out Caspase-9 *and* avoid breast cancer phenotype in our mouse model?

I am trying to design a wet lab experiment with no wet lab experience to name. Right now, in my dream land, it would be excellent if it were possible to create a Caspase-9 knockout mouse (damage to ...
6
votes
2answers
91 views

Intuitive explanation for Kin- and Group- selection

It is known from theoretician in the field of kin selection that kin selection (inclusive fitness theory) and group selection are actually two sides of the same coin. In other words, these two ...
4
votes
0answers
29 views

Do ant colonies prioritize survival of particular members above others?

In some (perhaps small) human communities people may starve because they have no income. This could be interpreted as a consequence of them not participating in the community, hence they don't get any ...
4
votes
2answers
311 views

What are the ESSs among hawks, doves, retaliators, bully and prober retaliators? [closed]

In his book "The Selfish Gene", Richard Dawkins says that retaliator emerges as an evolutionary stable strategy. But I think dove is also a kind of retaliator and so if dove increases, the hawks and ...
2
votes
1answer
17 views

Are Sciomyzidae fit to combat snails?

I read that Sciomyzidae are also called snail-killing flies, which immediateley made me think: "I need those"! Questions: Are they really fit to control snail over-population in my garden? and if ...
3
votes
2answers
137 views

Could an action potential produce few or more neurotransmitters based on the stimulus received?

I reckon that if you would be able to widen the AP width, it would produce more neurotransmitters in that larger time interval. Is that correct? Or does the neuron have a standard amount of ...
-1
votes
0answers
25 views

Blood test result. [closed]

I got my blood test result today. I found that my Haematocrit is 52% (Normal for male is 40-50), my lymphocytes is 42% (Normal for male is 20-40). What should I do to improve these kind of things? ...
-1
votes
0answers
28 views

How do we use ornithology to aid the survival of birds? [closed]

I only have a very lay understanding of the field.I have come across the following: We investigate the historical factors and current conditions influencing variation in the survival, ...
6
votes
1answer
65 views

Time lapse between fresh blood's exposure to air and that same blood turning darker red-brown

For investigative purposes, I'm searching for a tool that can be used as a quick visual assessment of the the length of time that blood has been exposed to air after the blood flow has stopped.. Let's ...
8
votes
1answer
77 views

What is the difference between organelle membranes?

Cells and organelles are contained in lipid bilayers. I'm particularly interested in eukaryotic organelle bilayers and the biophysicochemical differences between them. Many papers assume a ...
30
votes
4answers
4k views

Do plants produce any heat?

Many plants (e.g. roses, palms) can be protected from frost during the winter if shielded with an appropriate coat that can be bought in garden shops. Do plants produce any heat that can be kept ...
2
votes
1answer
128 views

Green Film Build up in Glass Water Bottle

So I have this Large Water Jug that I fill only water with. And this is the 2nd time there has been a layer of green film that builds up at the bottom of the bottle. I don't have any way of getting ...
8
votes
1answer
63 views

Why are people unable to develop lasting immunity against Norovirus?

Infection with many viruses will result in decades-long if not lifetime immunity, for example chicken pox. Because of the large number of viruses responsible for the common cold, lifelong immunity to ...

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