4
votes
1answer
54 views

Microbial Fuel Cell Reaction

I found a formula online which explained the reaction which occurred in the anode chamber of a microbial fuel cell but there was a typo $\small NADH + Ferredoxin_{(ox)} (NADH-Ferredoxin\ ...
2
votes
1answer
149 views

Why does crying lead to a running nose and reddened nose tip?

Why do we have a running nose for quite some time after crying? It persists even after we stop crying. Why is it so? I have faced this always. Also, why does our nose redden on crying for long?
4
votes
2answers
282 views

How many different protein coding genes are in the Human Biome?

There are approximately 20k protein-coding genes found in the human genome. This number is presumably very small when considering all the genomes found in the diverse microbes associated with the ...
4
votes
1answer
189 views

Why do we feel cold on having fever?

Why do we feel terribly cold on catching fever of any sort, however our body becomes hotter? Why is it that a rise in temperature makes the sufferer feel colder? Also, sweating symbolises betterment ...
3
votes
1answer
254 views

How does sucrose protect bacterial cells in lysozyme solutions?

I have a microbiology question. When we put bacterial cells in sucrose solution with concentration higher than 0.5M we observe plasmolysis - the cytoplasmic membrane detaches from the cell wall due ...
6
votes
1answer
66 views

Is telomere shortening consistant over consecutive cell divisions from zygote to a differentiated cell?

Considering the complexity of embryogenesis, a temporal referance would be helpful to coordinate the developmental sequences during embryogenesis and fetal development which is to be completed within ...
4
votes
1answer
66 views

Re-solidify disturbed agar plates

I am stuck in trouble while pouring LB agar onto my petri dishes. I had to add kanamycin to my plates just before it started to solidify, out of forgetfulness, which I tried to mix using the tip. The ...
7
votes
1answer
1k views

Dark veil when getting up too fast

I was asking myself this weird question. When you get up or stand up too fast, sometimes, you see something like a dark veil, and you aren't able to see anything distinctly for 2 or 3 seconds, then ...
9
votes
1answer
788 views

Did the eugenics program in Nazi Germany have a measurable effect? [closed]

Did the killing or sterilisation of people considered as living a "life unworthy of life" in Nazi Germany have any measurable effect on the "average health" of Germany? Is there any statistical ...
3
votes
0answers
81 views

Why are watermelons sweeter in the center?

Today I had a slice of watermelon and when I reached the outer parts of the pulp I wondered why those are less sweet. Whether or not the sugar occurs in crystalline form in watermelons is still an ...
1
vote
1answer
89 views

People say the cardiac cycle depends on blood pressure? How so?

I know what the cardiac cycle is. There are two phases diastole and systole. One is the relaxed, and the other is the contracted form of the heart. The diastole is where blood is pumped to the ...
9
votes
2answers
1k views

Is there any biological reason that professional swimming is dominated by white people?

I suppose that the question should be turned around to "Why is it extremely rare to see black people competing in professional swimming?" because it is the absence of this phenotype while watching the ...
2
votes
1answer
62 views

How do mushrooms react to being grown in a microgravity environment?

I'll use Agaricus Bisporus as an example mushroom. If cultured in potato dextrose yeast extract agar, will the resulting growth grow in a normal pattern? Will the sporocarps emerge from the surface ...
6
votes
1answer
198 views

Are there any other animals that become attached to a non-living object?

Do any animals become psychologically attached to any non-living object that is not useful to the animal for any of its physical needs, like some children do to stuffed animals? Some children are so ...
8
votes
1answer
1k views

If the xylem of a woody plant is composed of dead tissue, how does sapwood become heartwood?

If the xylem of a tree is composed entirely of dead tissue, then that means the sapwood is dead. If so, how does it transform into heartwood, and what starts the process?
0
votes
1answer
1k views

How do ants know where they are going without eyes? [closed]

I know that ants have some sense of direction, but what is the physiology behind this sense?
3
votes
1answer
250 views

Are there any air-plants with parts that are edible for humans?

Are any air plants (Tillansia sp.) safe for humans to eat? I haven't been able to find whether or not there are. Pineapple is in the same family (Bromeliaceae), but isn't an air plant.
2
votes
2answers
5k views

Why aren't we allowed to refreeze previously thawed breastmilk in refrigerator?

https://www.breastfeeding.asn.au/bf-info/breastfeeding-and-work/expressing-and-storing-breastmilk Previously frozen— thawed in refrigerator but not warmed 4 hours or less (ie the next ...
2
votes
3answers
123 views

How did the horned lizard evolve?

It's a lizard that has the ability to burst blood vessels in it's eyes and shoot blood as self defense. How can this behavior be explained evolutionary? Wouldn't it mean that there had to be some ...
4
votes
1answer
373 views

Would a spinal injury decrease human height?

A woman I know has been losing height at a rate of few cm a year following a severe spinal injury. How is this possible? What kind of injury could cause such progressive loss of height? Could this be ...
13
votes
1answer
346 views

Do fake wasp nests actually fool wasps?

I have seen fake wasp nests sold as a deterrent against wasps and similar insects. Do they really work? Is there some scientific evidence for it? A related link: ...
0
votes
1answer
57 views

What attracts cells to: pathogens, professional antigen-presenting cells, and cells with an antigen on its MHC-1 protein?

I have a few questions in regards to attraction/stimulation in the immune system. What attracts leukocytes and antibodies to pathogens in the first place? What attracts CD4+ cells to professional ...
3
votes
1answer
82 views

What's the difference between diuretic veggies and alcohol that make the latter bad?

So I'm reading this article to Treat Fluid Retention and it suggests Eat foods with diuretic properties. But also Avoid drinks that will dehydrate the body such as tea, coffee and alcohol. ...
5
votes
2answers
95 views

What are some atypical examples of positive transcriptional cooperativity?

Cooperativity in gene expression is an important feature of many regulatory networks. Described using the Hill function, the most common example is a transcription factor (TF) that when bound to its ...
3
votes
0answers
91 views

Why doesn't honey spoil quickly? [duplicate]

Why is it that honey can last for decades and not spoil like other foods? Is there any chemical in honey which gives rise to this amazing feat?
2
votes
1answer
137 views

Can foxes move their ears independently?

I've read that dogs can do move their ears independently, i.e., point one ear in the direction of a sound without having to point the other one at the same time. Is this a common trait with other ...
5
votes
1answer
137 views

By what mechanism can hypoglycemia induce fainting?

Hypoglycemia (Low blood sugar) is said to be among the potential causes of human-faintings. I was wondering by which mechanism this happens. Google search results are abundant; there are lists of ...
3
votes
1answer
154 views

How much energy is required to blind someone?

As I understand the ravages of sunlight upon the (human) eye; the cause of ocular damage and blindness is too much energy delivered to the cones and rods that ultimately make up our eyes; so the ...
26
votes
1answer
3k views

Is humans' height ideal?

More or less we humans are around 1.70 meters tall. My question is, would it be possible to scale us? that is, is it in principle possible having humans 1 cm tall, or 10 meters tall or is there some ...
6
votes
1answer
93 views

Location of nucleotide synthesis and transport

I couldn't find this question directly asked so I thought I would ask it In Fundamentals of Biochemistry 3e (Voet et al), it has a small small little comment about pyrimidine synthesis: (In a diagram ...
3
votes
1answer
104 views

Horizontal gene transfer versus convergent evolution

There are several often noted examples of convergent evolution (eyes, bat/bird wing evolution etc.) How do we rule out horizontal gene transfer in these cases?
15
votes
4answers
3k views

Height and natural selection in humans?

I watched the documentary "Evolve" recently and in the segment on "size" Scott V. Edwards, Harvard evolutionary biologist mentioned the idea that humans might evolve to be 7' tall in 'hundreds of ...
4
votes
1answer
945 views

how many abdominal sclerites would be there in a cockroach

Every tegmina of a cockroach has Sclerites which are homologous to the bones of humans. Every abdominal segment of cockroach consists of two lateral sclerite plates called pleura along with a dorsal ...
1
vote
1answer
250 views

Can I identify this black ant queen?

I have an ant queen in a jar. This is what she looks like: Because I'm planning to start an artificial ant nest, I'd like to learn something about that specific species of ant. This particular ...
2
votes
1answer
113 views

To what extent do domestic animals understand language?

Note: Please tell me to re-post this in Cogsci or pets if this doesn't belong here. Hello All, I want to know how dogs or other domesticated animals differentiate between normal chat and a command. ...
5
votes
1answer
167 views

High frequency human genetic oscillators?

The most well studied genetic oscillators in human genomes are involved in regulating the circadian clock (which operates on an approximately 24-hour cycle) and cell cycle activity (with single cycles ...
3
votes
1answer
254 views

Identify this Harvestman

I spotted this guy in Switzerland. It's clearly an Opilione (Harvestman), but I really know nearly enough about this diverse group to be able to identify the species. Sorry, I didn't think to ...
9
votes
1answer
209 views

First RNA polymerase-mRNA

We know that RNA polymerase produces mRNA by reading DNA strand. Which enzyme produces the first RNA polymerase if other RNA polymerases are synthesized in the same way like other enzymes(proteins) ?
2
votes
1answer
147 views

tetrads in meiosis are held together by what

This is from SAT subject biology test practice question. The answer it gave me was both chiasmata and centromeres. I can understand they are held by chiasmata but why also centromeres? I looked it up, ...
3
votes
1answer
36 views

In chromatin, what are the differences among states, interactions, and structures?

I am new to the study of chromatin, and I am trying to understand what people mean when they write about chromatin states, chromatin interactions, and chromatin structures. What are the difference ...
8
votes
1answer
340 views

How should I feed and keep an ant queen?

I have captured wandering ant queen. I guess she was just fertilised and was looking for a place to start a hive. I'd like to create my own ant hive in artificial environment. I unfortunately only ...
5
votes
1answer
189 views

Lost Ability to Regenerate Body Parts during the Transition from Amphibians to Mammals

Why have higher-order animals lost the ability to regenerate body parts during evolution? Wouldn't it be better for survival? What is the evolutionary theory behind it?
2
votes
2answers
395 views

By what mechanism does elevated homocysteine level cause endothelial dysfunction and damage?

It has been stated that elevated homocysteine level causes endothelial dysfunction and damage. By what mechanism does this happen? Why is it the endothel where elevated homocysteine causes problems? ...
1
vote
1answer
128 views

Question about the DNA glycosylase enzyme assay/formamide gel loading buffer

Often for the DNA glycosylase enzyme assay we can see that the DNA glycosylase is incubated with oligonucleotide in 37C and then reaction is stopped by addition of formamide gel loading buffer (80% ...
2
votes
0answers
80 views

Why Mammals are unable to produce Essential Fatty Acids?

While we have to get them from our diet and if they aren't taken in our diet we will face disease.Then why we don't have the enzymes which are require for EFA synthesis???
5
votes
1answer
89 views

Why might you NOT observe a tradeoff between two life-history traits?

I have traditionally thought of and heard about life-history traits (e.g., size at first reproduction, number of offspring, size of offspring, survival, etc., etc.) as drawing from a finite pool of ...
12
votes
3answers
258 views

Why do some fruits have a much wider range of acceptable sizes than others?

Some fruits such as pumpkins can grow to be 100 lbs. Under different conditions, the same variety of pumpkin can produce a 15 lb. fruit. Both plants are healthy, and look the same except for their ...
0
votes
1answer
152 views

Schedules of mating for men

It’s simple deductive logic to follow that for a species to survive it must provide it’s offspring with the best possible conditions to ensure it’s survival – either that or to reproduce in such ...
0
votes
2answers
115 views

How can you explain the origin of life out of nonliving matter (abiogenesis)? [closed]

According to biochemist Robert Shapiro, the "primordial soup" theory is as follows: Early Earth had a chemically reducing atmosphere. This atmosphere, exposed to energy in various forms, produced ...
3
votes
2answers
4k views

Cranial Nerve Decussation

I want to get my head round this once and for all so if you guys could help me would really appreciate it! I understand lesions to the optic nerve. It is the other nerves that I find difficult. So ...

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