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4

This is not as hard, as it first seems. Lets have a look at the single enzyme digests first: The digest with enzyme A and B only leads to products which are 5kB (5000 bp) away from each other. Since they are of the same size, both equally sized restriction fragments appear as one band. So each enzyme cuts the plasmid exactly in half. The double digest is a ...


0

Cloning of animals typically involves: Taking nucleus from healthy adult cell of animal to clone Taking a healthy egg and replace the egg's nucleus with nucleus from source animal. Implanting egg in female, stimulating the pregnancy process. This same process should work on humans BUT: "Is it really possible to create humans in lab?" No. Animal cloning ...


2

The term intergenic is more or less obsolete now. In fact it is ironical to say that a gene, which can give rise to a functional protein or an RNA, is expressed from an intergenic region. However the usage continues for both lncRNAs and miRNAs (other major type of ncRNA in metazoans1 - piRNAs have different classification). lncRNAs are vaguely classified as ...


13

Short answer: The two parents transmit the same amount of genetic information to their offspring ....or almost Long answer: Nuclear versus Cytoplasmic DNA All Eukaryotes (everything that is neither a Bacteria nor a Archeabacteria) have nuclear and cytoplasmic DNA. Most of the DNA is nuclear DNA. As it's name indicates, nuclear DNA is found in the nucleus. ...


3

Let's set things straight. The genomes of humans are highly similar and in general everyone shares the same genes. SNPs, or Single Nucleotide Polymorphisms, are single basepair positions in the genome in which there tend to be differences between people. This means, that instead of measuring the whole genome sequence for a person, which is very expensive and ...


0

From the statistical point of view, this question is rather vague. One would need a mathematical definition for the term "genetic variance". In one extreme, if the "genetic variance" merely means the categorial variations of nucleotides (i.e. ACTG) in the pooled genomes of interest, then the distribution of total "genetic variance" vs. loci variation is ...


2

I can understand your confusion but it all makes sense. The basic idea is that what we call the "antisense" strand is actually the one being transcribed. However, since that is in effect a mirror image, it is much simpler to think in terms of the sense strand. To take a very simple example: 5' ATG 3' <-- sense strand 3' TAC 5' <-- antisense strand ...


2

To address the "reason behind the question" - no, this doesn't work as you seem to assume it does. It is the whole point of sexual reproduction to have two slightly different copies of the genome. Mutations are not "corrected" within an organism, because they are not considered a bad thing per se. Mutations are "corrected" across generations, in the sense ...


1

See this document on how Illumina sequencing works. When you are doing a single end sequencing, the reverse strands produced after the bridge amplification + denaturation (step-7) are specifically removed (clipped at the junction of primer and the "insert" region). Furthermore, the free 3' ends are blocked (by chemical modification) to ensure that there is ...


5

Addition to other answers. Usually a human cell is diploid. Sometimes there might be extra copies of a chromosome and this phenomenon is called aneuploidy (Downs Syndrome, Klinefelter's syndrome etc). This always has deleterious effects because of changes in stoichiometries of different gene products (dosage effect). Some other organisms also tolerate ...


5

Diploid cells contain two copies of the genome. Additionally, each copy of the genome can have multiple copies of certain genes. Which can provide a level of protective redundancy. However, there are a number of potential problems with having multiple copies of portions of the genome such as trisomy disorders (e.g. Down Syndrome). Which is why therapy like ...


12

As a quick answer, yes, most human cells carry 2 copies of the genome and are known as diploid cells. One copy comes from each of your parents, so they aren't identical, but usually pretty close. Sperm and egg cells only carry one copy of the genome and are known as haploid. During fertilization the 2 cells merge their copies and make a diploid zygote. At ...


0

Presumably they removed one set of fragments from their figures for clarity of demonstration. In reality, both fragments remain immobilized on the chip. The sequencing primer only anneals to one adapter which allows selective extension of one of the sets in each run. For fragments of sufficient length, this provides an easy mechanism for creating paired end ...


4

Addition to Chris' answer. If you do not have a strain that doesn't produce biofilm then you would have to screen for the genes that are involved in biofilm production (this goes for any phenotype). In earlier times people used to do this by random mutagenesis with mutagens such as EMS (Ethyl Methanesulphonate) or UV. Nowadays it is possible to build a ...


7

You could do different things: First you could, as you say yourself, sequence the complete genomes of the strains from a biofilm and compare these with some, which do not form biofilms. This may give you an idea which genes are involved when they are present in the "biofilm genome" but not in the other. The proof would be to disrupt these genes either by ...


3

You probably mean genomic and non-genomic DNA - Plasmids are small rings of non-genomic double-stranded DNA in Bacteria. They replicate mostly indepently of the genomic DNA can can occur from a few to several hundred copies per cell. See the illustration from the Wikipedia:


0

You can fairly easily substitute peptides (short proteins) from the outside of the body, but you have to supply them by injection. They don't survive the low pH of the stomach unless you encapsulate them into an acid-resistant matrix. Short peptides are often very local and short acting, present only during specific times of the embryonic development (for ...


3

This is very likely to be parthenocarpy, which is an “internal proliferation” and varies from an irregular fruit to an almost carbon copy of the larger pepper. What is known is that it shows up in seed lines through natural selection and is unaffected by weather, pests, or other external conditions. Please see page 27 of this document.


2

The term was pioneered by Mendel, who had no knowledge of chromosomes, so definition 1 would perhaps be the best answer. However, we now know that definition 1 arises from definition 2 (chromosomes are inherited independently of each other) and from the fact that chromosomes recombine (cross-over). That said, independent assortment does not apply to linked ...


2

You can also try Lehninger Principles of Biochemistry...It covers all the topic except the part about cell motility...& possibly, the 1-A-g ( I'm not too sure about it)...but the book is for pretty advanced levels...& I would not recommend it as a last minute reference book..but for thorough study it's great....& of course it's my personal ...


1

Stryer's Biochemistry is a great book that pretty much covers all the requirements except those in A1 - Those are basic chemistry concepts which are not covered in Stryer. Any basic chemistry book will cover that. Make sure to verify, one-by-one, that all the test subjects are covered in Stryer. This answer is just a recommendation for a great Biochemistry ...


1

One of the chief components of centrosome is γ-Tubulin. In this study the authors have reported the effect of γ-Tubulin knockout in mice. Quoting the abstract: Gamma-tubulin regulates the nucleation of microtubules, but knowledge of its functions in vivo is still fragmentary. Here, we report the identification of two closely related gamma-tubulin ...


1

There is no literature report saying such a thing. However, I did a cursory check for GWAS study on neuroblastoma. Selected SNPs with p-value>0.05 Converted p-values to a score — -log10(p-value) Mapped the SNPs to genes while calculating cumulative score for a gene I just sorted the genes based on their names, assuming that many paralogs have similar ...


3

There are some more places other than what Bez has already mentioned. See here. However, tagging collagen may be a problem. Collagen undergoes a lot of post-translational modifications including hydroxylation and end clipping. It forms a unique structure (triplex) and adding tags may compromise its structural integrity. You can try Masson's trichome stain ...


2

Not to forget that simple cross breeding your plants the Mendelian way also modifies their genetic make up, as @souvik bhattacharya indicates in his comment. No equipment necessary, no chemicals, no ethical issues.


6

Genetic code and codons are always used with reference to RNA. When talking about DNA, the the sense strand of a gene is considered its sequence. The anti-sense strand though is the template for mRNA synthesis, does not represent the gene. DNA-codon table has simply U replaced by T. Apart from a wikipedia article, I don't find the term being popularly (not ...


2

Mutations can be caused by much more than just recombinatory events--polymerase fidelity, DNA damage repair, even environmental factors can have a huge impact on DNA damage. While most DNA polymerases have an error rate of around one mutation per billion, there are different levels of fidelity among different polymerases (McCulloch and Kunkel, 2008). ...


1

It's a popular public sentiment that - GM foods like tomatoes (flavr savr) will affect our health.. Is there any logical scientific explanation behind this? GM organisms can have different genes and gene expression than natural ones, so they can create more protein or different proteins. Proteins can be toxic, can cause allergy and can catalyze ...


4

Vision deteriorates for both reasons, but I'm not quite sure how to separate the effects of aging from wear and tear. Cataracts are the leading cause of blindness in the world. Ways in which environment (which falls under the category of wear and tear in my book) affects cataract formation: UV light: people living at high altitudes (e.g. Tibet) have ...


2

The comment by @fileunderwater is apt: stress-response-related genes are genes that are activated during stress, such as exposure to heat. In bacteria, for example, there are heat-shock proteins that are involved in keeping the tertiary structure of proteins (folding/3D shape) intact during periods of heat exposure. Genes encoding these heat shock proteins ...


0

Apart from what WYSIWYG said. It might also be the case that you need to re-sequence because you're interested in seeing the changes that might have occurred since the last sequencing. Remember that cells keep dividing and therefore changing, so the DNA is slightly different from one cell to another (and from one population of cells or tissues to another). ...


0

I assume that you mean gene expression regulation when you say genetic processes. The best example for your question would be that of synaptic plasticity in neurons. The immediate responses are obviously that of protein modifications (cell signaling). These are fast responses that have immediate effects but are also quite short-lived. During the long term ...


1

Hypomorphs (now commonly termed 'dominant negative') have a reduced (hypo) phenotype as compared the wildtype. Null (knockout) mutations, however, have the phenotype removed, so to say. The reason that you would use null rather than hypomorph mutations to do double mutant analysis is because with the hypomorph, you would still see some effect of the ...


1

Is that correct that a complete DNA sequencing (the whole genome) need only to be done once (per person)? Likely, yes. But I think you vastly overestimate how often this is done. If someone gets their DNA "sequenced" at 23andMe, for example, they are not getting their whole genome sequenced. They are getting individual bits believed to be possibly ...


1

Generally speaking, heterochromatin or euchromatin structures mark specific regions to regulate the transcriptional activity and these marks carry the signature of developmental processes as they differ in different tissues (or cell types). Therefore, we should not ignore the developmental processes if we want to understand how such epigenetic marks are ...


1

Non-coding transcripts can be as small as 10-15 nucleotides. Once the RNA polymerase initiates, the DNA is melted and the transcription bubble forms. This region is about 10 nucleotides long. But if you are asking the limit of mRNA length, then the answer is different. First of all, to get a protein, the ribosomes have to translate the transcript. To do ...


3

This study of the recently sequenced pine species states that 82% of genome is repetitive. This is characteristic of any complex genome, including humans. Such sequences have often been considered "junk DNA", though any scientist will tell you that just because we don't know its purpose doesn't mean it doesn't have one. That said, a good portion of repeats ...


1

The Law of Independent Assortment: Alleles for different traits are distributed to sex cells (& offspring) independently of one another. This one is like written on the stone in my mind!


2

Most mutations to the DNA are heritable, but not all are inherited. Mutations occur in the DNA, DNA is then replicated and transmitted to offspring (cells or organisms). Generally all mutations are heritable because they can be inherited, but some aren't - either by random chance (drift) or deleterious fitness effects (selection). Any mutation which makes ...


0

If all you cared about was genomic integration, then your best bet would be some kind of sequencing. If you sequence the modified region and the flanking regions you could be sure that the new sequence was present in the genome. It would probably be more interesting to look at how the new genes affect the cell. For example you could look at differences ...


2

Penetrance describes the frequency of a gene's expression: Penetrance refers to the proportion of people with a particular genetic change (such as a mutation in a specific gene) who exhibit signs and symptoms of a genetic disorder. (Genetics Home Reference nih.gov) More specifically: [P]enetrance is defined as the percentage of individuals with a ...


1

That's a valid explanation, but not definition. Mendel's law of independent assortments states that during the formation of gametes, the alleles for one trait segregate independently of the alleles of another trait.


2

I don't know what you really mean by "heritable changes to the genome". I think you will understand why this sentence makes no sense after reading what follows. I start with some background and then try to address directly what confuses you. Short introduction to the concept of heritability The concept of heritability may have two meanings. Heritability ...



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