All Questions

0
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0answers
6 views

Do mammals use uricotelic excretion?

Mammals use the enzyme xanthine oxidoreductase to oxidise purines to uric acid. Then, uricase is used to convert uric acid to allantoin. If they are able to do this, then why do we say that mammals ...
0
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0answers
18 views

DNA->RNA->Protein

For an RNA Molecule: 1) Adenine content equals to Uracil Content 2) Guanine content does not necessarily equal to its Cytosine content 3) Adenine content does not necessarily equals to uracil This ...
0
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0answers
5 views

What would cause taphonomic enlargement?

What would cause a fossil to be larger than the original specimen? I suspect that several factors could occur. Water retention, concretion, misidentification and so on. It is known that the reverse ...
0
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1answer
24 views

Does a mutation in the coding strand of a particular gene impact the polypeptide formed?

Recently, I came across this picture which represents the coding strand of DNA. The Altered picture shows a mutation in the base sequence (frameshift?), where a T base is deleted. The coding strand ...
1
vote
1answer
23 views

Can light function as a neurotransmitter?

Any animal with an eye has photoreceptors, which are essentially light-sensitive neurons. Green algae have channelrhodopsin, which are ion channels that open and close in response to light. Clearly, ...
1
vote
1answer
14 views

Balancing selection vs introgression?

Balancing selection can maintain polymorphisms in natural populations for extended periods of evolutionary time. However, in this paper, Dannemann et al. 2016 identify three archaic haplotypes in the ...
0
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0answers
8 views

What noise can a person with aphonia (loss of voice) not make?

I have been searching on Google using varying search terms but none of the sites I have found have given me a clear answer. Please, explain it to me like I'm five because I'm not great at biology.
0
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0answers
5 views

What mechanisms exist to reduce calcium excitotoxicity in a gabapentin tapering patient?

Gabapentin is postulated to have multiple mechanisms of action. However, most focus has been on its role in modulating L-type voltage gated calcium channels. Tolerance to, or reduction of, ...
1
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1answer
20 views

Which molecule that an excess of inhibits B-oxidation?

Which molecule that an excess of inhibits B-oxidation? a. Acetyl-coA b. Malonyl-coA This question is so debatable, because both are correct However, according to my professor, only one is ...
0
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0answers
14 views

Can someone have HSV-1 both orally and genitally?

Suppose person X has oral HSV-1. Can X get genital HSV-1 from person X' with genital HSV-1?
0
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0answers
11 views

Characteristics of tubal fluid

Tubal fluid is present in the fallopian tube. What is its color? Is it off-white/yellowish? Also what role does it play in fertilization (apart from being a place where it happens), specifically with ...
0
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0answers
14 views

Are there examples of Apis mellifera of different colors?

Re: my previos species-identification question, What species is this gray bee? I'm still curious: Are there any recorded/reported cases of either albino Apis mellifera, or at least with substantially ...
1
vote
1answer
29 views

In what fluid does the sperm swim in the oviduct?

We know that after sexual intercourse, sperm enters the female body and continues to pass through the oviduct by swimming. "Swimming" implies the presence of fluid. I want to know what that fluid is ...
0
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0answers
14 views

growing bacteria [on hold]

You are growing Bacillus subtilis in nine 16,000-liter fermenters to produce enzymes for industrial use. The Bacillus cultures had been growing for 2 days when the cells in one of the fermenters lysed....
1
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0answers
34 views

Could bone marrow transplants be used to prevent tissue rejection of trans-species organs?

So the immune system doesn't calibrate (for want of a better euphemism) to recognize it's own cells until fairly well along in fetal development & the major components of the immune system (...
0
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0answers
5 views

Do we add cyclic AMP (c-AMP) to the control group while doing differentiation of Endometrium stromal cells?

I'm performing an experiment using Endometrium cell lines split in 5 wells of 6 wells plate. 1st well->control day 0->0 hours 2nd well->control day0, 6hours 3rd well-> day0, 6 hours->treatment with C-...
2
votes
3answers
80 views

Strand representation in the DNA version of the Genetic Code

A Wikipedia entry entitled DNA Codon Table states that the codons presented in the table are on the ‘sense strand of the DNA’. But what is the purpose of this, if the sense strand doesn’t code for ...
0
votes
1answer
42 views

How do these triplets code for these proteins?

I am slightly confused by the diagram above. The first codon of the unaltered DNA is AAG. During transcription, isn't this coverted to UUC (mRNA). So doesn't UUC code for phe and not Lys? Likewise, ...
-1
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0answers
18 views

Why do Pythons have vestigial limbs and Colubrids not, despite the Python being more evolved (i.e. dual fanged and evolved in a later epoch)?

Pythons and Boas are the only species of snakes that have Vestigial Limbs, yet Colubrids are evolutionarily less advanced (they are monofanged and existed in an earlier epoch). My question is: why did ...
0
votes
1answer
32 views

Can diet, supplementation and/or drugs affect sexual dimorphism?

After puberty, can certain diets, exercise, and/or possible drugs affect masculine/feminine dimorphism in adults? We know dimorphism and/or morphology is a product of genes, but to what extent can ...
-1
votes
1answer
26 views

Does applying a sedative via hypodermic needle anywhere in the body really work?

Bad Guy is fighting the Good Guy. Good guy miraculously produces a syringe and rams it into the Bad Guy's neck. Cut, From my middle school biology I aware that capillaries are present ...
2
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0answers
19 views

Pre-linnaean names, where can I ask about current IDs?

I run a large website with lots of historical herb books. For the older ones, finding out current botanical names is very difficult. Can I ask here? If not, does anybody know where I could ask what ...
-1
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0answers
21 views

How would a human wearing earth clothes die on mars? [duplicate]

Please answer immediately If a astronaut out of her spaceship onto mars without her spacesuit, but just wearing her earth clothes, would she die first from suffocation, boiling fluids, freezing, or ...
2
votes
1answer
33 views

What is meant with “the chest wall and lungs are coupled together”?

Since the lung and chest are elastic, we can represent them with springs. Under normal conditions, they are coupled together: the “lung” springs are stretched and the “chest” springs are compressed. ...
3
votes
0answers
25 views

What is the thickness of the biosphere?

In other words, what is the vertical distance between the deepest and highest point on Earth where life is found? Life has been discovered at the bottom of the Mariana Trench, 13 km below sea level. ...
3
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0answers
11 views

What anatomical structures do baleen whales use to vocalize?

What anatomical structures do baleen whales use to vocalize? How does this differ between species?
1
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0answers
17 views

(secondary) human/primate advantages over other animals?

I am trying to understand the advantages that humans have over other species, besides what you could call 'sentience-critical'. What I mean by this is, the first set of answers you'll get is "more ...
8
votes
2answers
276 views

Are STOP codons impacted by base insertion or deletion mutation?

I am learning about base insertion and deletion mutations. An example in my textbook is given below. GUU CCA CAU AUC. So if there is an insertion (of guanine): GUU GCC ACA UAU C_ _ (there will be a ...
0
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0answers
17 views

Can meerkats swim?

Can meerkats swim? I've been doing a bit of looking at animals that can and cannot swim, and it looks like most mammals can swim. However, I was never able to find any relevant information on meerkats,...
4
votes
1answer
19 views

Can multiple cetacean species communicate?

It seems that individuals within the same species have their own communication, but is there evidence to suggest that individuals from different species are able to communicate?
0
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0answers
5 views

Parapatric speciation and hybrid zone

Does parapatric speciation make the biggest hybrid zone between allopatric,parapatric ,peripatric and sympatric speciations??
-1
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0answers
11 views

What is the probability of transmission a genetical feature of a particular organism to another organism? [duplicate]

What is the probability that a specific feature of an organism will be transferred to the after generation? What are the ways of artificially doing it? What are the factors that play a major role in ...
0
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0answers
16 views

What ailments used to be completely fatal (or nearly so) but, now modern medicine has a treatment or cure?

My brother was a Type 1 diabetic and back in high school I did a report on diabetes. One of the things that struck me was that before 1921, type 1 diabetes was basically 100% fatal. I was wondering ...
0
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0answers
25 views

Join a linear plasmid just using a primer (without ligase enzyme)

Can I use just a primer and PCR to join the cutted plasmid like this ? without using any further enzyme like ligase. After the linear dsDNA plasmid annealed into 2 ssDNA, primer will bind to middle. ...
2
votes
0answers
41 views

Are there any organisms, extant or extinct, that have only one neuron?

Nervous systems are useful in one way because they allow for integration of complex information. They are also useful because they transmit information very rapidly, over a large distance. However, ...
4
votes
1answer
19 views

Why do humpback whales sing songs?

Scientists have documented that it seems to only be male humpback whales who sing structured songs, but do we know what purpose their songs play?
0
votes
1answer
15 views

Are cryovials really better than regular tubes for cryopreservation?

What is the rationale for using cryovials instead of regular, sterile centrifuge tubes for the storage of mammalian cells? With a good aseptic technique and without touching the cap directly, there ...
-2
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0answers
12 views

How the modern science/ research help address issues related to haemoglobin [on hold]

Can you please help me with questions 7 as it’s a homework due on Monday I need to get the answer before Monday (https://i.stack.imgur.com/PdlgN.jpg)
0
votes
0answers
9 views

Tricuspid and bicuspid valves (structural difference)

Why does the tricuspid valve consists of three cusps while the bicuspid valve consists of only two? Does this involve the reason being that the left ventricle's cardiac muscles are stronger ana if so ...
2
votes
1answer
26 views

Why does tetracycline have such a broad spectrum of activity?

What are the structural and chemical characteristics that make tetracycline uniquely broad spectrum? I understand it acts on the A-site of the prokaryotic ribosome, but there exist many ribosome-...
0
votes
0answers
10 views

cell proliferation and cell mass proliferation

How are the increase in cell number (by division) and increase in the total cell mass (the sum of all the mass of all the cells) related ? Meaning can cell divide without taking some mass from the ...
0
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0answers
7 views

GFP intensity after proliferation and life time

I'm interested in knowing : What is the life time of GFP in a cell ? After division, does each "daughter" cell express GFP like the "mother" ? Meaning is there any loss in the expression of each cell ...
-3
votes
1answer
43 views

Why Km of an enzyme is half of Vmax ?Is there any other reason than when it is supposed as substrate concentration?

Any other specific reason other than substituting value of Km to substrate concentration.
0
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0answers
8 views

What does this part mean “ the narrowing part tends to maintain itself”?

When the vessel is narrowed by artherosclerosis, the velocity of the flow increases in the narrowed part and the distending pressure in that part decreases. This means "the narrowing part tends to ...
1
vote
0answers
8 views

Mild introduction to selective advantage of intelligence/nervous systems in animals?

I have a general understanding of why intelligence, i.e. nervous systems in animals, is advantageous: processing information allows an animal to adapt to its environment dynamically and perform ...
-1
votes
0answers
17 views

Principles of inheritance and variation

A fruit fly is hemizygous for sex-linked genes, mated with normal female fruit fly, the males specific chromosome will enter egg cell in what proportion?
2
votes
1answer
14 views

Technical reason that specialized embryonic cells form

During the embryonic stage of human development, rapid cell division occurs and specialized cells form to build the various parts of the developing fetus. I'm curious: Why technically do specialized ...
0
votes
1answer
39 views

Can vaccines move from person to person?

Can someone who has been given a vaccine "infect" another person with the virus used in that vaccine? For example, let's say Bill is vaccinated against tuberculosis. If Frank is exposed to Bill, is ...
2
votes
0answers
30 views

Is there a mechanism of timing or delaying the expression of gap genes?

Summary Gap genes are expressed in presence of the right combination and amount of transcription factors. But is there any additional mechanism of timing the expression of the gap genes to ensure ...
0
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0answers
18 views

What are the mechanics behind cell division? [on hold]

I understand the basics of mitosis. Or, at least, the Biology 101 stuff. But the other day it occurred to me that I have no idea how cells split. Like, the physical and mechanical part of it. Do the ...

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