3
votes
1answer
96 views

How do small birds survive the winter?

I live in a region with cold winters (ca. -40 C) and many quite small birds (sparrows, crows, ducks) stay for the winter. How can the birds survive this? As I understand it, smaller bodies will be ...
5
votes
3answers
480 views

3-minute long inspiring videos on evolutionary biology

What I am looking for I would like to start my teaching sessions with short emotional, awe-inspiring or exciting videos that are somehow related to evolutionary biology (incl. diversity of life, ...
0
votes
0answers
11 views

Which ScoreMatrix and GapPenalties should I use?

I'm a Software Engineering student, and I'm dealing with a Sequence Analysis problem. The problem is the following: Find phenylalanine hydroxylase of at least six different species, then perform a ...
0
votes
1answer
60 views

Which steps occur in each phase of Meiosis and Mitosis [closed]

MITOSIS In mitosis am I correct in saying that the spindles attach to the centromeres at the end of prophase/prometaphase? (I read this in an answer to another question) MEIOSIS Does the ...
1
vote
0answers
19 views

how to calculate dilution factor and CFU

I'm very confused I did a bacterial experiment where i added 5 grams to 70ml of distilled water that contains 10g of fresh meat. I left it in a sampler container over 24 hours then i cultured ...
0
votes
1answer
185 views

What are the minimum conditions required for “open-ended evolution”?

According to a paper about artificial life systems, the following four conditions have to be fulfilled for "open-ended evolution": Condition 1: A rule should be enforced that individuals must ...
0
votes
1answer
47 views

probe amplification in MLPA

I'm reading an article about MLPA (Multiplex ligation-dependent probe amplification) and I got stuck on this sentence: The advantage of splitting the probe into two parts is that only the ...
0
votes
0answers
22 views

About electrons returning to photosystem I when supply of NADP runs out in photosynthesis

According to my textbook, in photosynthesis, when the supply of NADP runs out, electrons from photosystem I return to the electron transport chain that links the 2 photosystems and flow back to ...
7
votes
1answer
82 views

About acetyl-coA in the Krebs Cycle of respiration

In respiration, Krebs cycle starts with acetyl coenzyme A which is made from pyruvate. However, it is said that the cycle keeps repeat it self with oxaloacetate turning back to citrate and cycle ...
4
votes
1answer
220 views

Could a trans-female person ever become pregnant?

I was told that a transgender person, which I will define as anyone assigned male or female at birth that identifies opposite to that assignment, could never become pregnant conceptually, due to the ...
5
votes
0answers
54 views

Do “scars” in humans replace all the skin layers or only some layers?

When someone has a cut or surgical incision that results in a "scar", is the scar tissue replacing all 3 layers of the skin (epidermis, dermis, hypodermis)? Or only the first one or two of them?
5
votes
0answers
23 views

Why sympathetic and parasympathetic nerves originate in different parts of CNS?

Curious if there is a reason for having: parasympathetic nerves originating from brain stem and pelvic part of spinal cord sympathetic nerves originating from thoracic and lumbar parts It looks ...
0
votes
1answer
47 views

Why only mitochondria and plastids?

Why are there only two unique semi-independent organelles? Why are there no others, symbiogenesis seems like it should be a relatively common thing. So do most organelles just lose all their DNA? Or ...
0
votes
0answers
30 views

Can an inhibited enzyme be activated by an activator molecule binding to a second allosteric site?

Can the inhibition caused by a inhibitor molecule(ATP that attaches itself to an allosteric site of a subunit of the PFK-1) be reversed by the binding of an activator molecule (AMP that binds to an ...
4
votes
2answers
328 views

Why are human titin and mice titin considered the same protein?

I have a book that says: In humans titin is a chain of 34,350 amino acids, but in mice it is even longer with 35,213 amino acids. If two polypeptides had different amino acid sequence lengths, ...
2
votes
0answers
48 views

What are the identifying characteristics of a Jellyfish?

I was walking down the beach today (Wollongong Australia, near Sydney) and saw this Jellyfish washed up on the beach. Then I saw another. I wanted to work out what type it was but didn't know ...
1
vote
1answer
63 views

Why are nucleic acids negatively charged at physiological pH? [closed]

Why do nucleic acids and mononucleotides have a negative charge physiological ph?
4
votes
1answer
36 views

Determining the Accuracy of DNA Testing

The DNA Testing firm in the below article claims that its tests were "99.99 per cent" accurate. http://www.telegraph.co.uk/news/uknews/1322077/False-DNA-test-led-father-to-reject-daughter.html ...
-2
votes
1answer
214 views

Bootstrapping (symmetry breaking) in evolution [closed]

Many fascinating phenomena in nature show different behaviours on the micro and the macro level. Here I am especially referring to phenomena that are symmetric on the micro and asymmetric on the macro ...
3
votes
4answers
122 views

Is an egg classified based on the species inside it, or by the species that laid it?

Basically what I'm asking is if an animal of species x were to lay an egg, and the animal inside that egg happened to be the first member of a genetically new ...
3
votes
1answer
38 views

How are individual neuron firing rates characterized?

I'm reading this paper that the Human Brain Project published in Cell and I'm confused how they recorded the firing rates shown in the firing below: In the publication, they mention that they use ...
1
vote
0answers
20 views

Why only human have noticeable difference in face? [duplicate]

Our facial appearance is pretty much different from each other unless we are talking about twin. Credit goes to crossing over of chromosome. But why can't we distinguish between other animals of same ...
0
votes
1answer
37 views

Where can I find a file listing the genetic differences in humans?

I don't know much about genetics. For an arts project I'm looking for a human genome. I read that: Only about 0.1% of the genome is different among individuals, which equates to about 3 million ...
1
vote
0answers
18 views

Can you grow more Biomass in a brickhouse only powered by solar cells than in a greenhouse? Will we ever be able to?

So I asked following question some physicists but they couldn't really help me though: Right now I read that 1m² of solar cells generates roughly 100Watts of energy. There are really efficient ...
0
votes
1answer
357 views

Are there animals / mammals which only have one eye?

Do all animals (of a certain size and not thinking about worms) have the possibility to perceive depth? Do all mammals have at least two eyes? Are there mammals with more than two eyes?
14
votes
2answers
906 views

What is the term for “technical extinction” of yet alive animals?

What is the term for an event in which a species is still alive, but has no chance of future reproduction and the species will be considered extinct once the current generation dies out? For example ...
4
votes
1answer
54 views

Are there testosterone receptors in female mammary tissue?

Does female mammary tissue have receptors for testosterone hormones? Do male hormones influence female mammary glands, as female hormones influenced the male mammary tissue, such as in gynecomastia? ...
2
votes
0answers
40 views

How to predict cancer-related proteins in Protein-Protein Interaction networks [closed]

Protein-Protein Interaction networks are known. It's an undirected graph. Each row of the networks is like this (Protein 2 - Protein 6), and It represents the interaction between Protein 2 and Protein ...
0
votes
0answers
19 views

Does physical exercise of a specific part affect muscles in the other parts of the body?

There is a theory among bodybuilders, that is, if you train big muscle groups (e.g. legs, chest), it will increase the overall growth of muscles all over the body; the trained muscle will release ...
3
votes
1answer
103 views

In the video, “Inner Life of a Cell”, what's the empty space between the molecules?

In the video, "Inner Life of a Cell" there's a lot of empty space between the proteins. Is it just a simplification (i.e. they omit smaller molecules)? If so, what are the smaller molecules supposed ...
0
votes
0answers
24 views

Can Allergy and Auto-immune diseases be the signs of hyper-vigilant immune system?

Allergy sufferers are much less likely to get some types of cancers. Theories regarding allergy - cancer link are mixed. Many say it is due to hyper-sensitive immune response. But the correlation ...
3
votes
0answers
37 views

Why does my grass luminesce when I step on it?

I live in Austin Texas. My grass is in pretty bad shape but I have noticed small luminous spots on some areas after I step on them. I'm guessing this will be seasonal so, for the record, this is ...
2
votes
0answers
31 views

Blood sampling at home

I want to collect small blood samples at regular intervals (e.g. every 8 hours or more often) over a longer period (weeks to months). To avoid having to go to a lab or doctor to have this done, I want ...
0
votes
1answer
45 views

How does the brain train its neural network?

One question that came up learning how artificial neural networks are working was how the brain can train its neural network? When we say we have an artificial neural network, the problem behind it ...
0
votes
0answers
42 views

Indentation between trapezius and scapula

I've been studying the muscles of the back, and while browsing through reference pictures on google I've come across this image (coloured lines edited in by me): What I'm confused about are the ...
0
votes
0answers
10 views

Quality assurance of mammography and false negatives by kVp?

Mammography is RTG imaging with customized constraints. False positives are most commonly associated with the imaging. However, there are sometimes false negatives where you cannot see the ...
0
votes
0answers
72 views

Is hypoxia/anoxia the ultimate cause of death?

I know there are different causes of death for humans like heart disease, cancer, stroke, injury and so on, but i was thinking if in every case in the last instance death is due to hypoxia/anoxia. ...
0
votes
0answers
19 views

How does a viral capsid undergo self assembly?

We know that viral capsids are formed by self assembly but there is surprisingly little information about how it is done specifically. Can somebody find video representation along with explanation, ...
0
votes
0answers
32 views

Where can I find the pathway for cAMP signaling in Dictyostelium?

I wanted the cyclic-AMP signaling pathway network of social amoeba Dictyostelium discoideum (which is necessary for the understanding of its "aggregation" life cycle) with rate constants and other ...
4
votes
2answers
108 views

Is there any evidence of animals wanting to die?

Is there any evidence of animals wanting to die? Specifically, animal communication which says "come and eat me".
3
votes
2answers
232 views

Indian tropical fruit trees and fruit bearing

Most Indian tropical fruit trees produce fruits in April-May. The best possible explanation for this is optimum water availability for fruit production. the heat allows quicker ripening ...
1
vote
1answer
53 views

Is it possible to have cancer and normal blood count at the same time? [closed]

Does cancer always cause abnormal full blood count? I've read on the internet that some people who had advanced cancer, also had normal blood count. I can't find anything on the internet about this ...
6
votes
1answer
103 views

Why would a python go after such large prey?

Here's a Python eating a crocodile: (photo credit Tiffany Corlis) I read that most Pythons would go for smaller prey, around the size of a house cat, but that larger species enjoy crocodiles, deer ...
3
votes
1answer
172 views

Small insect identification

I live in Chapel Hill, North Carolina, and recently started seeing a bunch of these little guys in my house. They're about 1/8" long (estimate), with brown/black zigzag stripes; it's possible they're ...
1
vote
1answer
60 views

Chromosomomal walking

I'm having a great deal of trouble understanding chromosomal walking, especially in regards to this article: Control of male sexual behavior and sexual orientation in Drosophila by the fruitless ...
4
votes
1answer
51 views

Determine which seed will germinate first

I recently studied about plant physiology for a test. Strangely, there was this question which I had no idea how to approach. The question is, Which seed will germinate first? a) Castor b) Wheat ...
0
votes
1answer
44 views

Which secondary structures of RNA are symmetric? [closed]

I'm trying to understand what is the meaning of this statement. A088518 Symmetric secondary structures of RNA molecules with n nucleotides. 4 %I %S ...
1
vote
1answer
29 views

How to choose secondary Antibody?

when isotype of the Primary antibody is IgG2a (from Mouse) and IgG2b (from Rat), how to choose secondary Antibody against these Primary isotypes? Does secondary Antibody is that much specific to ...
30
votes
4answers
8k views

If evolution is not about increased complexity, why does so much complexity evolve?

In my last question I asked why we don't see increased complexity in artificial life simulations of evolution. It seems I had fallen for a common misconception, that evolution was about improvement by ...
2
votes
1answer
82 views

Can the retina emit light?

The retina is light sensor, which converts light to an electrical signal. LEDs can both emit and receive light. Similarly, is it possible to apply electricity to retina to generate light? Simply ...

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