2
votes
0answers
37 views

Why are the largest land/air animals today smaller than in the Mesozoic?

The largest dinosaurs and pterosaurs seem to have been much larger than the largest animal terrestrial/avian species since. Was the Mesozoic somehow more hospitable to large animal species than ...
1
vote
1answer
148 views

Molecular Cloning- Blunt end restriction endonucleases

I work in a microbiology lab where we do a lot of cloning. I have always used restriction endonucleases to cleave the DNA to have sticky ends and not blunt ends. I currently am working on a project ...
13
votes
1answer
873 views

Are there birds with knees instead of elbows?

Are there any birds whose legs fold the same way human legs do, in a knee, instead of an elbow which is what all the birds I know have?
1
vote
0answers
45 views

Alkaline Phosphatase

What is the predominant purpose of Alkaline Phosphatase in skeletal muscle fibers and liver cells. I know that it is a hydrolase enzyme that speeds up the degredation of proteins, lipids, starch and ...
0
votes
1answer
51 views

Is there any research paper which identifies left and right brained behavior?

There are many web puzzle to identify, but does it really have any scientific proof? something like - http://braintest.sommer-sommer.com/en/ any logic behind it?
1
vote
1answer
59 views

Forum on synthetic biology and hypothetical biology?

I am interested in synthetic biology, but not a scientist, and would like some advice on where to look for an online forum on synthetic biology and creating fictional species and animals or if someone ...
7
votes
3answers
324 views

Why do I feel funny in my tummy when riding a virtual roller coaster?

I've ridden a virtual roller coaster on an Oculus Rift. I felt tension as I went up to the top, but more interestingly I actually felt my stomach drop when I went down the steep drop on the other ...
1
vote
0answers
113 views

Dead skin cell decomposition

What would be the resultant by-products of a completely decomposed dead skin cell? What would be the size of each of the by-products of a decomposed dead skin cell? How long would it take for a dead ...
1
vote
2answers
1k views

How do kidney cells excrete their own wastes?

The kidney is composed of tissues, and those tissues are made up of numerous cells - so how do these cells excrete their wastes? Lastly, are there any wastes in the venous blood (renal vein), what ...
5
votes
2answers
150 views

Burning fat transferred from one part of the body to another

While doing some research on cosmetic surgery, I discovered that there are several ways of doing breast enhancements, one of which was using body fat. While I haven't researched this method, I assume ...
3
votes
1answer
458 views

Is the activity of enzymes in the human body affected by the outer temperature?

I have to do a research about the enzymes in the human body and the things that affect them. I know that the body temperature affects the activity of enzyemes but I'd like to know if the outer ...
3
votes
1answer
98 views

Is there a maximum size for an insect?

I have read in biology text-books that one of the most important constraints on the size of an insect happens to be the importance of the surface-volume ratio. It simply states that if we assume ...
2
votes
1answer
82 views

Help me understand my membrane potential assignment

Epithelial with the ability to transport NaCl is bathed in an isotonic salt solution with these values (in mM): 136 Na, 6 K, 140 Cl. The intracellular concentrations are: 45 Na, 100 K, 13 Cl. The ...
6
votes
1answer
117 views

Which organs in the body are responsible for measuring temperature?

As an instrumentation engineer, I have designed temperature control systems capable of measuring and controlling temperature with a precision of 0.001K over a wide temperature range. I have always ...
8
votes
1answer
241 views

Hill's function for translational regulation

Transcriptional regulation is generally modeled as a Hill's function (similar to Michaelis-Menten Kinetics): $$\frac{dm_X}{dt}=\alpha _{m_X}.\frac{R}{K+R} -\beta _{m_X}.m_X$$ Where $m_X$ is the mRNA ...
5
votes
1answer
84 views

Can “human exclusion zones” in national parks for preserving Wolves and Grizzlies be a good idea?

There are National Preserves in the National Parks where some human activities are permitted. But can it make sense to create "exclusion zones" so no human would be permitted in a certain area, not ...
3
votes
1answer
93 views

What is the name of the critter depicted in the attached image?

I found a critter on my bathroom towel. It's really tiny. Maybe 2 milimetres? I placed it on an envelope for the photograph. Can someone identify what it is?
2
votes
1answer
66 views

Why is the vermis of the cerebellum associated with speech?

I've found multiple sources claiming that damage or impairment as a result of alcohol to the vermis of the cerebellum results in speech impairment. I find this a bit surprising, since the only areas I ...
1
vote
1answer
124 views

How can I compare the STRIDE and DSSP output files of a particular pdb file?

I have the pdb file of H-ras protein 5P21.pdb. I am supposed to compare the output of DSSP and STRIDE files after feeding this pdb file to respective servers. My question is how to make a quick ...
7
votes
1answer
304 views

What kind of fly is this?

I found this dude hanging out in my sink, but he didn't fly away when I put a dish in the sink. Turned out it was dead. The front part looks exactly like a housefly. But, I've never seen the back end ...
3
votes
1answer
2k views

What is the difference between rheobase and threshold?

Neuronal tissues can be excited by electrical stimulation. Two commonly encountered characteristics for electrically stimulating nerve cells is the threshold and the rheobase. My question is what the ...
1
vote
1answer
1k views

What is the difference between the basal membrane and the basal lamina?

I'm researching about the basal lamina in lung tissue and I'm not sure if the basal membrane is the same. What is the difference between them?
2
votes
2answers
2k views

How does non-homologous end joining (NHEJ) work?

I was reading about non-homologous end joining (NHEJ) in my molecular biology of the gene textbook but the explanation provided in the text was rather vague to me, and I was not able to understand it ...
3
votes
1answer
89 views

How are chickens affected by light?

When I was young, I was told never to put a fluorescent light in a hen house because it continuously turns on and off. Extra lighting is used, as far as I know, to 'extend' a chicken's day. Human eyes ...
1
vote
1answer
169 views

Which immunosuppression caused by long-term usage of these antibiotics in untreated celiac disease?

These antibiotics include amoxicillin + acidum clavulanicum (beta-lactam, inhibit cell wall synthesis, broad specturm, 3rd gen aminopenicillin) / last part preventing the resistance ceftriaxone (3rd ...
2
votes
1answer
57 views

Like size and colour constancy, why does the brain not maintain focus constancy?

I have progressive myopia. I grew up with perfectly normal eyes but slowly started getting myopic. The thing is, my brain knows (or should know) what the world looks like -- it knows that far away ...
1
vote
0answers
32 views

A good introductory book to histology?

Like the title says, I am looking for a good introductory text to histology. It would ideally cover sample preparation microscopy staining, and several example experiments Suggestions?
22
votes
4answers
3k views

Why do we need red blood cells?

From what I know, the main function of red blood cells is hemoglobin transport. So, why do we need cells packed with hemoglobin: why can't it travel freely in the bloodstream? My own thoughts were: ...
0
votes
2answers
758 views

What are the genus and species name of different breeds of dog?

Can you refer me to a good source containing the genus and species name of different breeds of dogs?
1
vote
1answer
23 views

Lateral corticospinal tract and termination

I'm studying the motor pathways of the brain and I'm a bit confused about how the lateral corticospinal tract descends. From Neuroanatomy: Text and Atlas by ...
2
votes
1answer
1k views

What is the mechanism of reflex arcs?

When a reflex arc occurs the signal from the receptor passes straight to the motor neuron instead of being passed onto the brain. This is a rather simplistic explanation, I was hoping to make it more ...
3
votes
3answers
98 views

Are there organisms that have incorporated plastic into their lives?

Are there organisms that have incorporated (manmade) plastic into their lives in any way? Either in their diet, or as a part of their body?
1
vote
0answers
55 views

Regarding benign tumors and what 'stops' them

Benign tumors can grow to dangerous size yet are they capable of metastisizing ; if not what stops this? Also with a benign tumor if you call its cells 'near' its edges its tumor 'cell wall' I was ...
0
votes
1answer
63 views

About the plight of Elephants and efforts to conserve them? [closed]

Poachers are only after the ivory horns right? I read this story from the New York Times ( I think) of saving a Rhinocerous by some Park Rangers and a Vet. ( forgive spelling) ; they tranquilized the ...
0
votes
0answers
61 views

Nystagmus drug FDA approval?

Congenital Nystagmus is an eye focusing disorder. It happens in manuals. Wikipedia lists several treatments on its page. Are any of those FDA approved for human use of that disease. drugs found ...
4
votes
2answers
284 views

How to visualize the ECM?

Specifically, I'd like to look at changes in HA (hyaluronic acid) production. Most often you only see people staining the cell surface or removing cells from culture for fixation and then imaging. ...
6
votes
2answers
2k views

Alternatives to trypsin for cell detachment?

I have ran out of trypsin and need to passage my cells (immortalized chondrocytes, C28/I2) today or tomorrow. I have been out of town and forgot to order more trypsin. I was wondering if there are ...
2
votes
0answers
105 views

Why is gynodioecy common and androdioecy rare?

Gynodioecy is when a population features individuals that produce both male and female gametes and individuals that produce just female gametes. Androdioecy is when a population features individuals ...
5
votes
3answers
2k views

How does protein denaturation work?

I was wondering how protein denaturation works. Are there covalent bonds, such as disulfide bridges involved, or is it based purely on non-covalent bonds such as hydrogen bonds? Why is denaturation ...
1
vote
2answers
154 views

How does high-fidelity of DNA replication depend on the formation of hydrogen bonds?

Replication has an error rate of less than 1 in 100 million. DNA polymerase forms H-bond with the H-bond acceptor atoms in the minor groove. <-- enhance fidelity here? Binding of the triphosphate ...
11
votes
2answers
2k views

How long does the Ebola virus remain infectious on contaminated items or surfaces?

I'm sure there will be variation depending on what the contaminated item or surface is made of - linens, I could imagine, would remain dangerous for longer than a door-knob. But if the items are not ...
3
votes
0answers
54 views

How many cells are there in the apical meristematic tissue?

How many cells are there in the apical meristematic tissue? Looking at this picture... , I would tend to think that there are few hundreds cells in the meristem tissue. But I guess this is a ...
4
votes
2answers
136 views

Can Hepatitis be caused by Bacteria?

There are many information about viral hepatitis. But it is interesting for me, can bacteria cause the hepatitis too?
2
votes
1answer
213 views

What are the disadvantages of forbidding flights to and from the African Ebola region?

After looking through the available Stack Exchange sites, this one seems to come closest to the appropriate place to ask... Popular opinion, including my own, is that banning flights to and from the ...
2
votes
1answer
7k views

Does DNA replication in 5' to 3' (leading strand) need RNA primase?

https://www.youtube.com/watch?v=27TxKoFU2Nw In the above video it shows that during DNA replication, the lagging strand require RNA primase to add 3' -OH group for further addition of nucleotides. ...
0
votes
1answer
4k views

What are the risks of elevating the legs too regularly and when tired?

I started to to think the pathophysiology of elevating legs high next to the wall too often and when you are tired. I think possible manifestations some damage to valves of the veins (No!) because ...
0
votes
1answer
72 views

Book-recommendation: Biochemistry

I need to have a book which covers following topics two may also be fine: (a) Structure and role of carbohydrates, fats, fatty acids and cholesterol, proteins and amino-acids, nucleic acids. ...
6
votes
2answers
429 views

Problems understanding membrane potential

I understand that membrane potential is the difference of the extracellular and intracellular ionic charges, due to their concentrations. We say that the extracellular space has a charge of 0 and then ...
1
vote
1answer
168 views

Understanding intra and extracelullar concentrations (membrane potential)

I have 4 question (not homework) What happens to the cells membrane potential if: a) Na+ outside rises by 40mM b) K+ inside rises by 10mM c) K+ outside rises by 10mM d) A- (impermeable ion) ...
3
votes
1answer
35 views

Exon skipping in mammals

I've heard from several sources that the predominant form of alternative splicing (at least in mammals) is exon skipping. However, my personal evidence is only anecdotal: I've heard it and read it, ...

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