0
votes
0answers
62 views

The definition of leaf area index

In many textbooks, leaf area index (LAI) is defined as the total leaf area per unit ground area. I want to know LAI is defined only by leaves that are directly above the ground (e.g., perpendicular ...
5
votes
1answer
263 views

Why is it often the case that an enzyme is favorable only towards one direction of a reaction and not both directions?

In class when we're studying enzymes like amylase or protease it only works well when you're using it to break down compounds like polysaccharides. I'm just curious but why is it not possible for ...
1
vote
1answer
85 views

What is a detailed chemical explanation for describing how an enzyme may lower the activation energy of a reaction?

If you can provide some sound reasoning that touches on tertiary structures of proteins and does not use a lot of advanced chemistry jargon that might be really helpful, especially for an intro ...
3
votes
1answer
55 views

blastn: What substitution matrix is used?

I'm currently working aligning sequences, and I need to compute similarity between pairs of DNA 'words' of a particular length. For amino acids I am able to use the substitution matrices in Biopython ...
0
votes
1answer
40 views

velvet assembler contig lengths are wrong [closed]

Has anyone else found that the contig length listed on the sequence defline, and in other files, is 32 nt shorter than the actual sequence? Any idea why this might be and what to do about it?
0
votes
1answer
32 views

IBD-value and IBD-fraction

I have some questions about the IBD-value and IBD-fraction for two of the condensed identity states, $S_1$ and $S_7$. My questions: 1) Is the IBD-value for the individuals i and j two (2) in $S_1$ ...
0
votes
2answers
30 views

How can a sequence be downloaded from UCSC genome browser

If I have genome coordinates is there a simple way to download the entire intervening sequence from the UCSC genome browser? I found some fancy way of using ftp but I can't figure it out.
1
vote
1answer
70 views

Why insects are attracted towards light? [duplicate]

Many insects like bees, dragonflies, wasps and other small insects are attracted towards light. Sometimes they are in groups, sometimes they are in solitude. When the light source source is switched ...
1
vote
0answers
48 views

How does intron retention make the alternative transcript non-coding?

I faced with a non-coding transcript that specified as one the isoform of BIN1. It sounds that this isoform generated as a result of alternative splicing with a intron retained; am I right? However, ...
0
votes
1answer
49 views

Artificial Adrenalin

I was watching Sherlock Holmes - A Game of Shadows yesterday. I saw that he had developed a serum that causes a person to react like he has been injected with adrenalin. Watsons's dog fainted, I ...
1
vote
1answer
43 views

How do I offer a generous gift to sweet-seeking wasps, bees, hornets, bumble-bees?

I was having ice coffee and melon ice and after visiting the lavatory I saw that a wasp was having a good time with my already finished ice coffee. Trying to begin the melon ice the wasp kindly ...
0
votes
0answers
37 views

Why do I often see male robins with female robins?

Even when it is not breeding season for robins I still often see male robins with female robins. But why? I know that the male robin often chirps to find female robins within his territory. I also ...
2
votes
1answer
74 views

Fibronectin glass surface adsorption

Short summary I'm having a glass surfaces and I want to adsorb proteins onto them. I have no problem, when I first adsorb fibronectin (human) onto some areas and afterwards any other protein. The ...
2
votes
1answer
491 views

Black/dark-red smooth West African worm, full of red blood

This chap was strolling across my bathtub in Freetown, Sierra Leone, one day after very heavy rains and flash flooding. From its course, it appeared to have come up the bath plug from the drains. ...
3
votes
1answer
349 views

What are these white spots on a dracena

I have a Dracaena Marginata which started to have some white spots. They turn out to be some kind of "mold" which can be removed when swapping the leaf and then leaves some discolored spots ...
0
votes
1answer
83 views

In the future, it is plausible that we can change the physical appearance of a living animal by editing DNA?

http://www.independent.co.uk/news/science/revealed-scientists-edit-dna-to-correct-adult-genes-and-cure-diseases-9273555.html This article explains that scientists managed to change the DNA of adult ...
1
vote
0answers
23 views

What is the sedimentation coefficient of Mycoplasma?

I have attempted to find the sedimentation coefficient of a number of bacterial species, namely E. coli and a number of Mycoplasma species, but they seemed to be rather elusive in the literature. If ...
0
votes
1answer
86 views

What DNA has the most info for getting a person's likeness? [closed]

I understand that DNA can come from hair but also from other places. Let's suppose a person gets their DNA mapped by a company (there are some companies claiming to offer analysis of DNA.. e.g. maybe ...
1
vote
1answer
364 views

What is a selective constraint?

I encountered the term selective constraint in Huber et al. 2015, page 4 (last paragraph) in: If invariable sites are included in the analysis, then both the methods of Kim and Stephan ...
1
vote
1answer
74 views

Disease causing variants and Hardy-Weinberg Equilibrium

Is it true that many disease causing variants/mutations do not follow Hardy Weinberg Equilibrium? If so, then please elaborate on why this may be true (or not) and provide examples. I am interested ...
1
vote
0answers
47 views

How do mosquitoes react to blood feeding on a highly ethanol intoxicated host?

Considering that a mosquito can consume up to five times its body weight in blood during a single meal (Encyclopedia of the Arctic, M.Nuttal), and considering a very strong alcoholic intoxication of ...
0
votes
0answers
39 views

Effects of Fixation on Cell Membrane

Why does fixing of cells with something like formaldehyde disrupt the membrane enough for probes, antibodies, and dyes to get into the cell?
2
votes
1answer
76 views

Why do cells not spread on soft substrates?

I recently read a paper discussing how cells (primary mouse embryo fibroblasts) fail to spread and proliferate properly when plated on a soft substrate (i.e. soft PDMS pillars with stiffness k = 2.3 ...
20
votes
1answer
538 views

Why are many fruits sour?

Many fruits (like apples, berries, citrus fruits etc.) contain high levels of organic acids, especially malic acid and citric acid. Are there any evolutionary functions of those acids in ripe fruits? ...
1
vote
0answers
61 views

What are constrained genetic elements?

I am somewhat of a newbie in evolutionary biology currently taking my first steps in bioinformatics. I was reading a paper when I came across the term "constrained genetic elements", referring to ...
4
votes
0answers
77 views

What is the essence of difference of how different chemicals affect the same receptor?

It is known that various chemicals can bind to the same receptor type, producing different effects. Be these chemicals agonists or antagonists, there are more variations in how they influence the ...
1
vote
1answer
115 views

TSS of a gene vs TSS of a transcript

I have an annotation from gencode.vM1.annotation of a mouse. Exons, genes, transcripts and UTR are listed there. For each feature a start and end positions are present. I need to find a TSS for each ...
6
votes
1answer
95 views

Which organism is this?

Place: Bangalore, India Month: September, 2015 Current weather: Cloudy and rainy Google images search was just giving me dragonfly photos. That organism is on grass blade. Image is captured by ...
1
vote
0answers
130 views

why monocot roots have a wide pith while dicot roots have a narrow pith?

Normally dicot roots have a nartow pith at the center but monocot roots have a wide pith. Is there any specific reason to this?
0
votes
0answers
30 views

How many eggs are in each mature Taenia saginata proglottid?

What is the range and mean number as the number of eggs per proglottid is variable? By mature proglottids I mean those expelled naturally in human faeces (earlier tapeworm segments have fewer eggs I ...
0
votes
1answer
21 views

use of adjuvants and peptides in modern vaccines?

when preparation of modern vaccines we generally use a part of the microbe or the antigen such as polysaccharides to create an effective vaccine against the vaccine. so when the preparation of sub ...
1
vote
2answers
57 views

How can I find some pieces of the genome of a microorganism?

I have figured out how to download the fasta of the genomes of microorganisms, for example the botulism bacteria and the spirulina algae. However, I want to find a fasta file for some significant ...
0
votes
1answer
518 views

Amylopectin is insoluble in water while Glycogen is readily soluble

The only difference between the structures of Amylopectin and Glycogen is that Glycogen is more highly branched than Amylopectin. How this difference between their structures makes difference between ...
4
votes
1answer
163 views

How does NHEJ cause indels?

I was reading up on CRISPR-cas9 and how it works and I am having trouble wrapping my head around how NHEJ to repair the DSB can cause indels to occur. Shouldn't the NHEJ just stick the two strands of ...
0
votes
2answers
29 views

how to find full mitochondrial genome of plants in GenBank?

I am searching for full mitochondrial genome of a species of Malvaceae family. To be more specific, I need the genus Corchorus. ...
0
votes
1answer
42 views

What would be the estimated cost sequencing?

I'm a newbie to the world of NGS, but I thought it might be a suitable and cheaper alternative to doing traditional Sanger sequencing for this particular application. However, I'm not so sure on how ...
9
votes
1answer
1k views

Are all Y-chromosomes the same?

Since the Y-chromosome can only pass from male to male child, it would seem to pass intact. Thus, a boy's Y-chromosomes would, I guess, be the same as his father's. Going backwards, would not all men ...
1
vote
1answer
94 views

What factors cause males to be more common than females in humans, from an evolutionary perspective? [duplicate]

Fisher's principle states that there should be a 1:1 ratio between males and females born on average for a population. However, if you look at birth statistics your find that boys are slightly more ...
0
votes
2answers
54 views

Do any predatorial animals attempt to appear smaller?

There are many animals that have behaviors or characteristics to make themselves appear larger than they are as a defense mechanism, such as butterflies have large eye patterns on their wings. Are ...
2
votes
1answer
256 views

How to understand certain protein names

I am looking for a reference to help me understand what is meant by acronyms such as : H3K9me1, H3K9me2, and H3K9Ac. I know that these are all histone proteins, but is there a general nomenclature ...
1
vote
1answer
240 views

How do DNA-binding proteins determine that they're binding to the correct DNA base pairs?

My professor posed this question to the class today - "How do DNA binding proteins specifically bind to base pairs?" He alluded to the different arrangements of hydrogen-bond donor and acceptors in ...
9
votes
3answers
560 views

Do spinal cord reflexes (such as the knee-jerk reflex) continue to function under general anaesthesia?

The knee-jerk reflex (patellar reflex) is an example of a stretch reflex (myotatic reflex). Stretch reflexes are monosynaptic reflexes happening in the spinal cord without involvement of the brain. ...
2
votes
1answer
77 views

Is blood pressure in the aorta and brachial artery the same or different?

Does the blood pressure at the root of aorta equal the blood pressure in the brachial artery? I've heard it does, but it doesn't quite seem to make sense as I'd think the blood pressure would be ...
0
votes
1answer
147 views

Normalised gene counts to edgeR/DESeq2?

Both very popular differential expression packages assume a raw gene matrix count. This makes sense because the statistical model models the library depth. But what if I normalize my counts with say, ...
2
votes
2answers
174 views

Does the human body convert water?

I just read Andy Weir's "The Martian" (which was very good) and one line made me wonder: [...] a human body only borrows water. Is that true? Does all water "that goes in, go out"?
1
vote
1answer
65 views

Plasmid copy number and Rop protein

If i want to transform a bacteria (E. coli) with a particular plasmid (in my case pBR322) will the presence of the Rop gene affect the production of it ? Is it desirable to use a plasmid without that ...
0
votes
0answers
46 views

Self assembly of Golgi Apparatus

Self assembly is not a new phenomenon to biology. Many things self assembled to provide full fledged functional unit. There are two conflicting theories about formation of Golgi Apparatus, Template ...
3
votes
0answers
53 views

Caterpillar identification

It has since cocooned I think but it was a weird circumstance. I kept adding leaves for it to eat, and it decided it was done, and cocooned under a wilted leaf. I'm wondering if anyone can ID the ...
0
votes
1answer
55 views

Expected dS/dN ratio for exome

I am trying to determine whether or not my sequencing data has more/less non-synonymous mutations than would be expected. My understanding is that there is some fixed ds/dn ratio for the human exome ...
1
vote
2answers
790 views

Are eukaroytic promoters located in the 5' UTR region?

I was wondering if promoter sequences are located on 5'UTR region in eukaryotic organisms?

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