Digital World Biology Articles

Displaying 81 - 100 of 748 Articles
Teaser Image

by Sandra Porter

If you've seen our blog posts about different forms of DNA (A, B, Z), nucleosomes, telomeres, or DNA sequencing, you might get the idea that we're a bit obsessed with DNA. And, you'd be right. We find DNA to be amazingly fascinating and beautiful, as well.

That ...

Teaser Image

by Todd Smith

A key concept in science is molecular scale. DNA is a fascinating molecule in this regard.

While we cannot "see" DNA molecules without the aid of advanced technology, a full length DNA molecule can be very long. In human cells, other than sperm and eggs, six billion ...

A key concept in science is molecular scale. DNA is a fascinating molecule in this regard. While we cannot "see" DNA molecules without the aid of advanced technology, a full length DNA molecule can be very long. In human cells, other than sperm and eggs, six billion base pairs of ...

Science Blog
Teaser Image

by Todd Smith

Linear chromosomes are hard to maintain.

Replication fork - http://en.wikipedia.org/wiki/Telomere.
Every time their DNA gets replicated, it gets shorter. This is due to the fact that DNA polymerase can only add bases to the terminal 3'-OH of a DNA chain. The DNA replication initiation complex uses RNA ...

Replication fork - https://en.wikipedia.org/wiki/Telomere. Organisms with linear chromosomes have to solve the problem that DNA replication makes them shorter. This is due to the fact that DNA polymerase can only add bases to the terminal 3'-OH of a DNA chain. The DNA replication initiation complex uses RNA primers to provide ...

Science Blog

Today (4/25) is national DNA day. Digital World Biology™ is celebrating by sharing some of our favorite structures of DNA. We created these photos with Molecule World™ a new iPad app for viewing molecular structures. As we are taught in school, the double stranded DNA molecule is a right-handed helix ...

Science Blog
Teaser Image

BLAST for beginners
This tutorial is designed as a quick introduction to the BLAST family of sequence analysis programs.
These slides show a progression of steps in using blastn, beginning at the home page for the National Center for Biotechnology Information (NCBI) ( www.ncbi.nlm.nih.gov) and ending at PubMed, a tool ...

Filed Under
Teaser Image

BLAST for beginners introduces students to blastn, a commonly used tool for comparing nucleotide sequences (DNA and RNA). This popular tutorial shows how to do a blast search with a nucleotide sequence, highlights information in the search results, and shows how to interpret the E value and alignment scores.

Filed Under
Teaser Image

DNA barcoding is an important technique for identifying many kinds of animals, insects, and plants. In this technique, PCR is used to amplify a short (650 base) region of the MT-COI gene from mitochondrial DNA. The DNA sequence is then determined from the PCR product. If this sequence has been found before, it can be used to identify the type of organism that contributed the DNA.

Filed Under
Teaser Image

Microarray and Next Generation DNA sequencing technologies have given us new abilities to understand how living things respond to environmental change. One of the ways we can use this new information is to study gene expression under different conditions. In this activity, we will explore microarray data from plants as they experience drought.

Filed Under
Teaser Image

This five and half minute video introduces some of the basic skills for using Cn3D.

Filed Under
Teaser Image

This six minute video describes some of the history of bioinformatics.

Filed Under

By Todd Smith

In our series on why $1000 genomes cost $2000, I raised the issue that the $1000 genome is a value based on simplistic calculations that do not account for the costs of confirming the results. Next, I discussed how errors are a natural result of the many ...

In our series on why $1000 genomes cost $2000, I raised the issue that the $1000 genome is a value based on simplistic calculations that do not account for the costs of confirming the results. Next, I discussed how errors are a natural occurrence of the many processing steps required ...

Science Blog

by Todd Smith

Previously, I introduced the idea that the $1000 genome has not been achieved because it is defined in simplistic terms that ignore many aspects of data completeness and verification. In that analysis, I cited a recent perspective by Robasky, Lewis, and Church [1] to present concepts related ...

Previously, I introduced the idea that the $1000 genome has not been achieved because it is defined in simplistic terms that ignore many aspects of data completeness and verification. In that analysis, I cited a recent perspective by Robasky, Lewis, and Church [1] to present concepts related to the need ...

Filed Under
Science Blog

by Todd Smith

Getting an accurate genome sequence requires that you collect the data at least twice argue Robasky, Lewis, and Church in their recent opinion piece in Nat. Rev. Genetics [1]. The DNA sequencing world kicked off 2014 with an audacious start.

Andrew Pollack ran an article in the ...

Getting an accurate genome sequence requires that you collect the data at least twice argue Robasky, Lewis, and Church in their recent opinion piece in Nat. Rev. Genetics [1]. The DNA sequencing world kicked off 2014 with an audacious start. Andrew Pollack ran an article in the New York Times ...

Science Blog

By @finchtalk (Todd Smith) We kick off 2014 with Finchtalk’s traditional post on the annual database issue from Nucleic Acids Research (NAR). Biological data and databases are ever expanding. This year was no exception as the number of databases tracked by NAR grew from 1512 to 1552. In the leadoff ...

Science Blog