0
votes
0answers
20 views
3
votes
1answer
34 views

Richard Goldschmidt's “systemic mutations”?

[TLDR] I dont understand the fault people had/have with Richard Goldscmidt's concept of systemic mutations [/TLDR] As a preface, I am a undergrad biology student, so sorry if this is a "Stupid ...
2
votes
1answer
45 views

Markers for human genetic mapping

For human genetic mapping several different types of markers are used: RFLPs (Restriction Fragment Length Polymorphisms) VNTRs (Variable Number of Tandem Repeats) such as mini- and microsatellites ...
2
votes
0answers
19 views

Cholesterol's role in lipid uptake

I'm studying the digestion of fats and I understand that our dietary fats mostly consist of triglycerides. We absorb the fats and eventually they end up in a muscle/adipose cell for storage (as ...
0
votes
0answers
18 views

Where does the oxygen and water produced from the decomposition of hydrogen peroxide by catalase enzyme go?

How are they disposed of by the body, or are they disposed of at all? Since our body needs water and oxygen anyway, I'm speculating that these "waste product" will be reused/recycled by the body in ...
1
vote
0answers
14 views

What kind of experiments could you do to see which end of a microtubule is most dynamic?

I'm stuck between two ideas. Not sure which one of them would be best. Do a FRAP on the middle of a MT. If it grows from the + end, that section will remain dark. If it grows from the - end, ...
6
votes
1answer
92 views

Why do women live longer than men?

According to Wikipedia and many other sources, women live substancially longer than men (over 5 years in the U.S.). Men can reproduce for much longer than women. So longer living men would have the ...
6
votes
2answers
236 views

What kind of bird species is this?

Every now and then I got a glimpse of this bird which I'm pretty sure is not native to Northern Germany where I live. There are at least three of these birds around but I usually only see something ...
5
votes
1answer
140 views

What is the maximum number of babies a human woman can have?

I know you could divide the female fertility period (~40 years, right?) by 9 months which would give something like ~50 kids (with no multiple kids per pregnancy). The limiting factor in this ...
2
votes
1answer
42 views

How can I use this data to make a function? [closed]

I'm currently in high school biology (final year) and am currently working on an assignment. I need to create some sort of interactive model, so I've decided to make a simulation-type program. I've ...
1
vote
0answers
17 views

Bolyerine Snakes maxillary bone, split?

How is the maxillary bone split in the Bolyerine Snakes described in T.H Frazzetta's "From Hopeful Monsters to Bolyerine Snakes?" In T. H. Frazzetta, "From Hopeful Monsters to Bolyerine Snakes?" He ...
7
votes
1answer
77 views

Does urine therapy really work?

I heard a lecture from a supporter of urine therapy and he says that urine is not only good disinfection, but also drinkable source of minerals. I said to myself that I can take either one or the ...
4
votes
1answer
50 views

What happens when someone is stung by a jellyfish?

What happens in the human body when someone is stung by a jellyfish; namely a box jelly. Judging by what I have heard about the stings I'm guessing that they involve a neurotoxin. But what is ...
5
votes
1answer
140 views

Where do amino acids get attached to tRNA and where is it synthesized?

Some very basic parts of transcription/translation seem to be left out in various literature. I can't find the answer to this anywhere: How exactly is tRNA synthesized? I realize that mRNA is ...
2
votes
2answers
56 views

What is meant by nucleated in this context?

Hi I am little confused in one of my classes; because the teacher will say that " the actin is nucleated by the ARP 2/3 complex" or "microtubles are nucleated by the centrosome". Unless I am ...
3
votes
1answer
23 views

Why introduction of an extra copy of a gene related to pigmentation causes RNA interference in Petunia?

RNAi became famous after Fire and Mello experiment in C.elegans; however, it had been observed before. In the 80's, Jorgensen was trying to increase pigmentation of Petunia flowers by introducing ...
0
votes
0answers
13 views

Solid mouse (C57BL/6) WT primers

I am trying to get a good pair (or better yet, library of pairs) of primers that give me one band in WT mice (C57BL/6). Do you know where I could find such a thing? Alternatively, I thought of just ...
3
votes
1answer
33 views

What is the statistical relationship between radioactivity and mutation rate?

This question tries to narrow down the scope of that question. What is the statistical relationship between radioactivity and mutation rate? By how much would the mutation rate be lowered in a ...
1
vote
1answer
30 views

Myopia as a microscopic superpower?

A few years back my Physics professor made a joke that his Myopia/Nearsightedness gave him a "superpower" that allowed him to see close objects much more clearly than someone with typical eyesight. ...
2
votes
2answers
40 views

What are the typical values of probabilities for nonspecific binding to an antibody?

I'm physicist by training, so please excuse me if I don't use the proper terminology. I think there is a way to make a sensor that detects if a single antibody has caught something from the flow. So ...
2
votes
2answers
93 views

Core Biological concepts explained to a Computer Scientist?

I am a computer scientist delving into Bioinformatics and I need to gain insight in biological phenomena. How would you explain three core concepts as: Evolution, Selection and Variation, to a ...
2
votes
0answers
21 views

Why do naked mole rats live in colonies with a queen?

What was the evolutionary advantage in having queens? Is it because the ones that had queen like tendencies in the new environment had kids that cooperated better giving higher chance of survival of ...
32
votes
5answers
1k views

Why do men have nipples?

I'd be tempted to call nipples in men vestigial, but that suggests they have no modern function. They do have a function, of course, but only in women. So why do men (and all male mammals) have them? ...
4
votes
1answer
94 views

Water soluble molecules

I believe I may have misunderstood water solubility this entire time. I assumed that water soluble meant that it would literally dissolve in water. It would break down into atoms. A sugar molecule ...
-1
votes
1answer
77 views

What is the function of dendritic cell in immunity?

I'm interested in how dendritic cells present antigens to helper T-cells? I'm also interested in the molecular actions between a dendritic cell and a helper T-cell during the activation of the helper ...
2
votes
2answers
27 views

What is the difference between meristem and bud?

Keep reading both terms quite frequently while studying plant physiology. I did some research trying to establish their differences and I learnt that meristems are undifferentiated cells that can ...
1
vote
1answer
51 views

How do the homologous chromosomes pair up and position themselves along the center of the cell? [closed]

I am not sure... Most textbooks just state "they line up" but I don't know how... Something to do with the cytoskeleton or microtubules? Thanks for any help
5
votes
1answer
91 views

Why does a “cascade” of events happen during signal transduction?

I've been watching some videos on signal transduction and it says that because there are enzymes being activated by the signal, then there is a "cascade" which happens afterwards...I don't understand ...
4
votes
1answer
497 views

How can haired mammals synthesize vitamin D?

The human body can synthesize vitamin D in the skin from cholesterol, when sun exposure is adequate. But how can haired mammals do it? Do not they need it?
8
votes
2answers
116 views

Why did humans evolved the scratch reflex?

I've been wondering about this for some time, and I can't come to an answer... Everybody keeps telling me that scratching one's own skin is bad. It damages the epidermis, creates the hazard of ...
8
votes
3answers
163 views

Splice in with CRISPR/Cas

I need to splice a gene into a human cell genome, with highest rate possible. I mean, doesn't really matter where the gene enters, nor does it matter if some cells die as a result of this. CRISPR ...
6
votes
2answers
49 views

Why are triacylglycerols broken down before being absorbed?

So when dietary fats are in the small intestine, they are emulsified by bile salts in order for action by lipases to occur. Lipases degrade the triacylglycerols into monoacylglycerols, ...
0
votes
1answer
50 views

Is it possible for humans to digest and live on food that isn't based on DNA or RNA? [closed]

Our bodies digest food using enzymes that have evolved to convert food here on Earth. Could we even possibly get nutrients from something we haven't evolved alongside? - Is it possible for humans to ...
1
vote
2answers
249 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 haemophilia? I think the ...
7
votes
2answers
118 views

Is it possible for a human to wake up in a wrong way?

There's an old folk saying that goes like "He got out of bed on a wrong foot" - to indicate that the person's day is going poorly because of the way that person woke up. Is it is possible for a human ...
0
votes
0answers
19 views

Selection Pressure on Orca Whale Coloration

What is the proposed selection pressure that leads to the distinctive coloration of Orca whales? I can find nothing in the literature.
5
votes
1answer
96 views

Mitotic crossover happens in G1?

I was reading this article in wikipedia and came across this : It has been suggested that recombination takes place during G1, when the DNA is in its 2-strand phase, and replicated during DNA ...
4
votes
1answer
25 views

Epistasis Across Chromosomes and Individuals 'Homozygous for Interactions'

Apologies for any failures in nomenclature. I'm a mathematician who is making a foray into genetics for a masters thesis. Specifically, I'm generating artificial diploid genetic sequence data and ...
1
vote
1answer
64 views

Alcohol and athletes? [closed]

I've seen a lot of articles claiming that alcohol has a very bad impact on athletic performance. Examples include, but are by far not limited to: ...
4
votes
2answers
56 views

SNPs in DNase hypersensitive and histone marks sites

I am investigating a role of SNPs in DNase hypersensitive sites and in the DNA regions of histone marks and have some questions about it. SNPs in DNase hypersensitive sites might mean that those SNPs ...
3
votes
2answers
277 views

What are evolutionary implications of contraception and reduced childhood mortality rates worldwide?

I've heard the following idea this morning: Before the introduction of contraception, humans conceived quite a lot of babies (there was little to do to avoid that), but the population was kept in ...
4
votes
1answer
49 views

Where to find E.coli gene expression data?

I am searching E.coli whole genome expression data with different conditions, any suggestion is appreciated. Condition could be for example different growth temperature, different medias, etc. I have ...
5
votes
1answer
1k views

What biological constraints are there on how large a spider can grow?

Spiders fascinate me, but what intrigues me the most is just how big some spiders can get, which leads me to my question. What biological constraints (if any) would limit how large a spider could ...
3
votes
1answer
102 views

Can Leptospirosis be spread through human urine

I am wondering if Leptospirosis can be spread via the urine of an infected human individual. All of the sources I have been able to find on the web have stated that the disease is primarily spread ...
4
votes
1answer
42 views

Do sweat pores change diameter?

In Cholinergic Urticaria, some people believe that the itching which is generally more in winters might be because that the diameter of sweat pores is less due to less activity(less sweat production) ...
1
vote
1answer
37 views

Clarification on the “orientation” of chromosomal rearrangements

I need some clarifications on the concept of "orientation" in case of chromosomal rearrangements. Given a deletion event on a chromosome for example, is the resulting DNA at the breakpoint always in ...
1
vote
2answers
351 views

Why can newborns swim?

I am wondering for someone to discuss the phenomena that newborn babies (humans) are able to submerge underwater up until a few months where that ability is lost again? What is the explanation for ...
9
votes
3answers
106 views

Is there a fundamental reason that plants cannot fix their own nitrogen?

Plants must have nitrogen to grow. According to the answer to this question, there are no plants can fix their own nitrogen (without the help of bacteria). Plants get their nitrogen in the form of ...
4
votes
1answer
2k views

Difference between intervertebral and vertebral foramina

In the human spine, what is the difference between intervertebral and vertebral foramina? Is it just a matter of perspective and do they refer to the same thing or are they different?
3
votes
0answers
53 views

Criteria for compound action potential thresholds

As opposed to action potential thresholds (which are binary yes/no events), electrophysiological thresholds of compound action potentials are arbitrary. Mostly a certain noise level is picked and when ...

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