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Nucleic Acids Calculator Enter Parameters OD260 OD280 Dilution factor DNA/RNA Stock Volume (ul) type of nucleic acid   select  dsDNA  RNA  ssDNA  ssOligo      Results measured DNA/RNA conc (ug/ ul) OD260/OD280 ratio stock DNA/RNA conc (ug/ ul) Total Amount of DNA/RNA ( ug) 1 OD260 Unit = 50ug/ml for double-stranded DNA 1 OD260 Unit = 40ug/ml for single-stranded RNA 1 OD260 Unit = 40ug/ml for single-stranded DNA 1 OD260 Unit = 20ug/ml for single-stranded oligonucleotides http://www.kenkyuu.net/js/nacalc.html

DNA fingerprinting in Medicine A   method   used   to   identify   multilocus   DNA   banding   patterns   that   are specific   to   an   individual   by   exposing   a   sample   of   the   person's   DNA   to molecular   probes   and   various   analytical   techniques   such   as   Southern   blot analysis. DNA fingerprinting  in Science       The   use   of   a   sample   of   DNA   to   determine   the   identity   of   a   person   within   a certain   probability.   DNA   fingerprinting   is   done   by   analyzing   repeating patterns   of   base   pairs   in   DNA   sequences   that   are   known   to   vary   greatly among ...

RNA stands for ribonucleic acid. It is an important molecule with long chains of nucleotides. A nucleotide contains a nitrogenous base, a ribose sugar, and a phosphate. Just like DNA, RNA is vital for living beings. RNA comes in a variety of different shapes. Double-stranded DNA is a staircase-like molecule. Image Credit: National Institute of General Medical Sciences Ribonucleic acid (RNA) has the bases adenine (A), cytosine (C), guanine (G), and uracil (U). Image Credit: National Institute of General Medical Sciences DNA compared to RNA DNA is defined as a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms. RNA molecules are involved in protein synthesis and sometimes in the transmission of genetic information. However unlike DNA, RNA comes in a variety of shapes and types. While DNA looks like a double helix and a twisted ladder, RNA may be of more than one type. RNA is usually single-stranded, ...

Can changes in the number of chromosomes affect health and development? Human cells normally contain 23 pairs of chromosomes, for a total of 46 chromosomes in each cell  (illustration) . A change in the number of chromosomes can cause problems with growth, development, and function of the body's systems. These changes can occur during the formation of reproductive cells (eggs and sperm), in early fetal development, or in any cell after birth. A gain or loss of chromosomes from the normal 46 is called aneuploidy. A common form of aneuploidy is trisomy, or the presence of an extra chromosome in cells. "Tri-" is Greek for "three"; people with trisomy have three copies of a particular chromosome in cells instead of the normal two copies.  Down syndrome  is an example of a condition caused by trisomy  (illustration) . People with Down syndrome typically have three copies of chromosome 21 in each cell, for a total of 47 chromosomes per cell. Monosomy, or...

How many chromosomes do people have? In humans, each cell normally contains 23 pairs of chromosomes, for a total of 46. Twenty-two of these pairs, called autosomes, look the same in both males and females. The 23rd pair, the sex chromosomes, differ between males and females. Females have two copies of the X chromosome, while males have one X and one Y chromosome. The 22 autosomes are numbered by size. The other two chromosomes, X and Y, are the sex chromosomes. This picture of the human chromosomes lined up in pairs is called a karyotype. Credit: U.S. National Library of Medicine

What is a chromosome? In the nucleus of each cell, the DNA molecule is packaged into thread-like structures called chromosomes. Each chromosome is made up of DNA tightly coiled many times around proteins called histones that support its structure. Chromosomes are not visible in the cell’s nucleus—not even under a microscope—when the cell is not dividing. However, the DNA that makes up chromosomes becomes more tightly packed during cell division and is then visible under a microscope. Most of what researchers know about chromosomes was learned by observing chromosomes during cell division. Each chromosome has a constriction point called the centromere, which divides the chromosome into two sections, or “arms.” The short arm of the chromosome is labeled the “p arm.” The long arm of the chromosome is labeled the “q arm.” The location of the centromere on each chromosome gives the chromosome its characteristic shape, and can be used to help describe the location of specific g...

Chromosomes & mtDNA Read about each of the human chromosomes and mitochondrial DNA (mtDNA) and the health implications of genetic changes. Information about specific chromosomes chromosome 1 chromosome 2 chromosome 3 chromosome 4 chromosome 5 chromosome 6 chromosome 7 chromosome 8 chromosome 9 chromosome 10 chromosome 11 chromosome 12 chromosome 13 chromosome 14 chromosome 15 chromosome 16 chromosome 17 chromosome 18 chromosome 19 chromosome 20 chromosome 21 chromosome 22 chromosome X chromosome Y Information about mtDNA