Dnatube Scientific Video Site

Helicases are a class of enzymes vital to all living organisms. They are motor proteins that move directionally along a nucleic acid phosphodiester backbone, separating two annealed nucleic acid strands (i.e. DNA, RNA, or RNA-DNA hybrid) using energy derived from nucleotide hydrolysis. Many cellular processes (DNA replication, RNA transcription, DNA recombination, DNA repair, Ribosome biogenesi...
Added: 1263 days ago From benchwork | global.duration: 103.10 | Views: 35340 | Comments: 1

This video shows structure of DNA and RNA. Ribonucleic acid or RNA is a nucleic acid polymer consisting of nucleotide monomers that plays several important roles in the processes that translate genetic information from deoxyribonucleic acid (DNA) into protein products; RNA acts as a messenger between DNA and the protein synthesis complexes known as ribosomes, forms vital portions of ribosomes, a...
Added: 1091 days ago From technician | global.duration: 319.53 | Views: 24086 | Comments: 2

Digestion occurs at the multicellular, cellular, and sub-cellular levels, usually in animals. This process takes place in the digestive system, gastrointestinal tract, or alimentary canal. Digestion is usually divided into mechanical manipulation and chemical action. In most vertebrates, digestion is a multi-stage process in the digestive system, following ingestion of the raw materials, most o...
Added: 1038 days ago From watchme | global.duration: 165.16 | Views: 20492 | Comments: 0

The signal recognition particle (SRP) is a protein-RNA complex that recognizes and transports specific proteins to the endoplasmic reticulum in eukaryotes and the plasma membrane in prokaryotes. The eukaryotic SRP is composed of six distinct polypeptides bound to an RNA molecule (the 7SL RNA), with GTPase activity. In the GTP-bound state, it recognizes an endoplasmic reticulum signal sequence of e...
Added: 1136 days ago From second | global.duration: 47.65 | Views: 18215 | Comments: 0

The biosynthesis of saturated fatty acids requires a primer molecule, usually acetic acid in the form of its Coenzyme A ester, and a chain extender, malonyl-CoA. The latter is formed from acetyl CoA by the activity of the enzyme acetyl-CoA carboxylase in which biotin is the prosthetic group (and thus can be inhibited by avidin). In the first step of the reaction, carbon dioxide is linked to the bi...
Added: 1127 days ago From mnazirokur | global.duration: 39.65 | Views: 16875 | Comments: 0

DNA fragment complexed with acridine derivative (a carcinogenic dye). Data source: Protein Data Bank code 2GB9. Wiki text info: Acridine, C13H9N, is an organic compound and a nitrogen heterocycle. Acridine is also used to describe compounds containing the C13N tricycle. Acridine is structurally related to anthracene with one of the central CH groups is replaced by nitrogen. Acridine, a colorle...
Added: 1085 days ago From adamsan | global.duration: 64.93 | Views: 14692 | Comments: 1

Deoxyribonucleic acid, or DNA, is a nucleic acid molecule that contains the genetic instructions used in the development and functioning of all known living organisms. The main role of DNA is the long-term storage of information and it is often compared to a set of blueprints, since DNA contains the instructions needed to construct other components of cells, such as proteins and RNA molecules. The...
Added: 1125 days ago From siere | global.duration: 497.71 | Views: 13718 | Comments: 0

This 2-part Maya animation depicts the process of nucleic acid packing/assembly into the viral capsid. Part I shows the process simultaneous with the measured kinetics of packing and force (displayed on the right). Video by Eric Keller Stylus Visuals
Added: 977 days ago From sertan | global.duration: 30.53 | Views: 11990 | Comments: 0

Wii text info: The central dogma of molecular biology was first enunciated by Francis Crick in 1958[1] and re-stated in a Nature paper published in 1970:[2] The central dogma of molecular biology deals with the detailed residue-by-residue transfer of sequential information. It states that such information cannot be transferred back from protein to either protein or nucleic acid. In other word...
Added: 1085 days ago From adamsan | global.duration: 15.23 | Views: 11805 | Comments: 0

This video shows how fatty acids are taken into the body and how it is processed from mouth to adipocytes. Fatty acids consist of the elements carbon (C), hydrogen (H) and oxygen (O) arranged as a carbon chain skeleton with a carboxyl group (-COOH) at one end. Saturated fatty acids (SFAs) have all the hydrogen that the carbon atoms can hold, and therefore, have no double bonds between the carbon...
Added: 1271 days ago From siere | global.duration: 0.08 | Views: 9976 | Comments: 0

Protein Synthesis, Translation Translation - the process of converting the mRNA codon sequences into an amino acid polypeptide chain. 1. Initiation - A ribosome attatches to the
Added: 503 days ago From admin | global.duration: 135.00 | Views: 9701 | Comments: 2

Histone deacetylases (HDAC) (EC number 3.5.1) are a class of enzymes that remove acetyl groups from an ε-N-acetyl lysine amino acid on a histone. Its action is opposite to that of histone acetyltransferase. Deacetylation removes acetyl groups from histone tails, causing the histones to wrap more tightly around the DNA and interfering with the transcription of genes by blocking access by tran...
Added: 1096 days ago From tubeman | global.duration: 197.70 | Views: 8981 | Comments: 0

ChromosomesChromosomes contain the genetic material deoxyribonucleic acid or DNA. In association with proteins, the twisted strands of DNA become coiled and folded to give chromosomes a beaded appearance. Each bead represents a gene-a length of DNA coding for the synthesis of one or more proteins. There are thought to be more than five hundred genes on each of the cell's forty-six chromosomes. Her...
Added: 1059 days ago From watchme | global.duration: 74.00 | Views: 8691 | Comments: 0

THE FORMATION OF URINE FIGURATION, REABSORPTION, AND SECRETION Every one of us depends on the process of urination for the removal of certain waste products in the body. The production of urine is vital to the health of the body. Most of us have probably never thought of urine as valuable, but we could not survive if we did not produce it and eliminate it. Urine is composed of water, certain ele...
Added: 503 days ago From arsinsol | global.duration: 290.00 | Views: 8680 | Comments: 0