2
votes
0answers
89 views

Bergmann's rule and Allen's rule: endotherms and ectotherms

Surface area to volume ratio (in terms of heat conservation) is not the only mechanism, but it is still an important mechanism for explaining Bergmann's rule and Allen's rule. Given that, I want to ...
1
vote
1answer
242 views

Why does SDS-PAGE use for protein, and agarose use for nucleic acid?

My question maybe very primary, but after I learned this part, questions always follow me. SDS-PAGE gel works for detect protein, agarose gel works for detect nucleic acid, so here is my question: 1. ...
0
votes
0answers
9 views

Promote heat to the body by enhancing thyroxine release

Production of thyrotrophin releasing hormone by hypothalamus activates the release of thyroid stimulating hormone, that induce the thyroid to produce more thyroid hormone in the blood. So my question ...
0
votes
0answers
33 views

How much force can connective tissue withstand?

I have been studying a 3D anatomy model. Based on visual observation, it doesn't look like the bones would be able to stabilize themselves at all without the connective tissue like ligaments. In the ...
1
vote
1answer
117 views

Viruses. Alive or Not? [duplicate]

I saw this fascinating article today about how HIV moves through a mouse host in real time. http://www.engadget.com/2015/10/02/watch-hiv-spread-through-mouse-in-real-time/#continued It's common to ...
0
votes
0answers
370 views

Pitch shift in hearing after wisdom teeth removal

Yesterday I had my wisdom teeth removed. This morning, when I heard our phone ringing, it sounded a little lower-pitched than usual (I have perfect pitch). Sure enough, when I opened FL Studio (music-...
1
vote
0answers
78 views

Reasons for strange heart rate graph following exercise (line going up and down)?

Following a 2 minute general jumping and movement exercise designed to involve the entire body, the pulse was taken every minute for ten seconds. Strangely, the graph appears to jump up and down, for ...
0
votes
1answer
36 views

Energy produced from respiration [closed]

Why is the amount of ATP Produced from anaerobic respiration is less than the amount produced from aerobic respiration?
1
vote
0answers
31 views

Will someone with a double mutation in the allosomes be normal?

Normally a female human has an X allosome from her father and an X allosome form her mother. What if an double mutation happened, which causes that someone has two X allosomes form her mother and no ...
1
vote
0answers
83 views

How to identify a pseudogene to a specific protein coding genes?

Pseudogenes are those sequences in the genome that bear similarity to specific protein coding genes, but nevertheless are unable to produce functional proteins due to existence of frameshifts, prema- ...
1
vote
3answers
215 views

Did we evolve from monkeys?

Since I was young, I always understood that evolution taught that we descended from monkeys (or apes, not too sure a distinction was ever made). However, someone recently told me that this isn't ...
4
votes
3answers
2k views

Chromosome 2 fusion?

I read this article by Jeffrey Tomkins and Jerry Bergman claiming to debunk chromosome 2 fusion. Is there anything wrong with these conclusions? " 1.The reputed fusion site is located in a peri-...
1
vote
0answers
70 views

Why did life on Earth develop with two sexes? [duplicate]

If evolution gives us the best adapted organisms for survival of the fittest, why does so many of Earth's organisms require two sexes for reproduction? Shouldn't this have been bred out of our ...
15
votes
4answers
3k views

Why do only two sexes exist for animals?

Why, from the natural selection point of view, do only two sexes exist for animals?
14
votes
3answers
61k views

What is the healing process of mouth wounds?

When we have an external wound, blood generally tends to clot there, forming a layer of solid scab. Yesterday, while brushing my teeth, I somehow hurt my gums and it got all bloody. However, it did ...
2
votes
1answer
24 views

How can I interface cAMP signal or membrane potential from slime mold to an electrode?

I am very much interested in measuring cAMP (cyclic adenosine mono phosphate) signal and membrane potential from amoeba. Since I want to try this as a hobby, what are the basic steps I must do to view ...
0
votes
0answers
74 views

How to calculate PAR and aPAR from reflected + incoming radiance

i have measured the reflected radiance of a plant and the incoming radiance with a point spectrometer from 300 to 700 nm in 1nm increments. How can i calculate photosynthetically active radiation (PAR)...
0
votes
2answers
242 views

DNA adaptation in human life

Does our DNA adapt by human lifetime? Or do we have the same genetic information from birth to death? I mean: What is usually called "evolution" means "natural selection" like this: http://www.youtube....
4
votes
1answer
447 views

Why can't we use plasmids to add genes to ourselves?

Reading these answers I wonder, why doesn't "gene therapy" use self-contained plasmids instead of trying to splice a length into a chromosome?
3
votes
2answers
85 views

How do muscles help erect the spine?

Muscles of the spine help to support it against gravity. For example, the multifidi interweave throughout the vertebrae and, as I understand, sort of reinforce the spine. So let's suppose muscles help ...
1
vote
1answer
109 views

How to find a Cancer PPI network data [closed]

I need a Protein Protein Interactions network of Cancer (any type - just I want a PPI of any type cancer), I search and see DIP PPI and .... How to specify that is Cancer PPI and how to get a PPI of ...
3
votes
3answers
102 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?
2
votes
0answers
29 views

Why are bovines different genera if they can interbreed?

Why are bovinae a "subfamily", above Genus, when members can interbreed? Some like the beefalo are fertile, which is the normal defining characteristic of a species. And Genus are groups more ...
0
votes
2answers
119 views

how do I find the number of bp in chromosome 3 by knowing number of bp in chromosome 1?

If i have a number of bp in chromosome 1 for example(298,295,559 bp) can I use this number to find the number of bp in chromosome 3.
14
votes
2answers
8k views

Why do we urinate more when we are nervous?

This question is a result of my personal experience... But I guess that is common for many of us. My school timing is 8:00 am to 1:30 pm (usually). During normal school days I typically urinate one ...
2
votes
1answer
150 views

Do drugs' levo isomers have a better interaction with the receptors in our body than dextro isomers?

Examples of levo drugs include levothyroxine, levocitrizine, and levodopa. Is there any specific reason why the receptors in our body exhibit this stereoisomerism and hold a high preference for the ...
1
vote
1answer
65 views

Human population growth - where can I find the data?

Out of curiosity, I'd like play around with data of human global demography. Where can I find data that describe the "per region (per continent for example) population size" versus time since the "...
8
votes
1answer
2k views

Can females be recreated from male DNA?

A chromosomal male is XY and a chromosomal female is XX. Now imagine if, one day, this world has only males - is it possible to "recreate" a female by using two X chromosomes from two different males?
5
votes
1answer
109 views

Can a lack of sleep degrade balance?

For years, I've noticed that the day after a night of poor sleep (4 hours or less), my balance noticeably degrades. For instance, while walking 20 feet to the coffee maker, I might stumble into the ...
0
votes
1answer
62 views

Does the human abdominal cavity use pressure to maintain posture?

Several of my PT friends have referenced a physical therapist p who has studied breathing named Mary Massery. In her articles, she has referenced the idea of "intra-abdominal pressure" http://www....
1
vote
0answers
53 views

Was this snake behaving abnormally?

This morning, I walked out front of my house to find a medium-sized snake balled up on my driveway beneath my motorcycle. I spotted it from my porch so I didn't walk any closer. I believe it was a ...
6
votes
1answer
639 views

Evolution home experiment?

If I were to take bakers yeast and put it in medium of minimal sugar(whatever quantity that would be) and rice(for a source of starch), could the yeast have a "evolutionary leap" and adapt to use the ...
2
votes
0answers
44 views

Can anyone please help me identify this plant? [closed]

Please help me identify this plant. My aunt had one but it died due to the drought in California. She wants to get a new one but she doesn't know what it's called. The leaves are around two inches and ...
-1
votes
1answer
329 views

What will happen if the biceps stop contracting and instead triceps contract? [closed]

For example if i bend my arm the biceps contract and triceps relax but if I bend my arm and the triceps contract instead of biceps what effect would it have?
4
votes
2answers
151 views

How do ascending neural pathways filter unimportant information?

In school they told us one of the functions of the ascending neural pathways is to filter unimportant information. But the neural signal I know, is only a chemical-electrical chain of neurons. Is this ...
14
votes
4answers
11k views

Why we have no enzyme to digest cellulose?

As we know, cellulose is the most abundant polysaccharide in nature. Why don't we have any enzyme to digest cellulose?
1
vote
2answers
241 views

How does DNA damage cause ageing in yeast?

As I understand it, in yeast ageing there is daughter cell and mother cell. The daughter cell is has newly "fresh" DNA and mother cell dies after some counts of replication. What happens to the ...
13
votes
2answers
1k views

Why and how does uniprot list around 150,000 proteins in the human genome?

Using organism:"Homo sapiens (Human) [9606]" as a query in uniprot returns about 146,000 proteins. I was under the impression that there were only 20-25,000 protein ...
1
vote
0answers
67 views

Why is it easy to separate the cotton wool from the roots of young plants grown in cotton?

In my book it is said that if we grow Maize and Gram seeds in wet cotton, after the seeds are sprouted it is easy to separate the cotton wool from the roots of young plants. My question is why is it ...
4
votes
1answer
67 views

How does Tylenol relieve pain without making me drowsy?

So I have a crown that popped out and has been killing me, I've lived on a steady diet of Tylenol since it popped out. I've noticed that aside from killing most of the pain from the tooth, the tylenol ...
1
vote
2answers
82 views

“structural and regulatory elements of genes” [closed]

Can anyone please explain a little about these two elements of genes? My main problem is with "which ‘switch on’ instructions". genes have structural elements (which code for a particular protein) ...
1
vote
1answer
66 views

meaning of “usually greater than 200 base pairs”

From "Risks from GMOs due to Horizontal Gene Transfer", by Paul Keese: Homologous recombination. All cellular organisms have molecular functions dedicated to recognizing and recombining DNA ...
4
votes
1answer
700 views

How can mammalian red blood cells live without a nucleus?

Even though they have a shorter lifespan than other varieties of cells, I would think that 120 days without a nucleus is still quite a long time.
1
vote
0answers
32 views

Invertase calculation?

If I wanted to make $500\mathrm{\mu g}/\mathrm{ml}$ of invertase, from Sigma's Invertase from Baker's yeast, which states is grade VII, and greater than or equal to $300 \mathrm{units}/\mathrm{ml}$, ...
6
votes
4answers
306 views

Can children restore brain cells?

By "children" I mean young people at the age of 10 or lower. I know that the adult brain cannot restore brain cells, but what about children? I mean, the brain must develop from a few cells to a 90 ...
10
votes
2answers
635 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 ...
1
vote
0answers
29 views

Why does hypergranulation prevent the epithelialization of a wound?

I recently read about how does a wound heals. I read that when the granulation tissue protrudes out of the wound bed (proud flesh), the epithelialization cannot occur because the protruding proud ...
3
votes
1answer
230 views

Does antidromic conduction occur in the brain under normal conditions?

So I am reading a book on neuroscience and they mentioned in passing that the action potential is capable of travelling in either direction along the axon (orthodromic vs antidromic), The wikipedia ...
4
votes
1answer
411 views

Saltatory conduction of nerve impulses

I am aware about some basics of saltatory conduction of nerve impulses. I know that the nerve impulses (ion flow and the depolarization) are transferred from node to node in myelinated nerve fibers. ...
3
votes
1answer
202 views

Membrane Permeability to Pyruvate

Pyruvate seems to pass easily through the outer membrane of the mitochondrion but has difficulty entering the inner membrane (and gets in by H+ symport). I have two questions: (1) what property of ...

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