4 DNA and gene transcription Questions How is genetic information stored in the cell? What is the structure of DNA? How is gene expression controlled? DNA and the chromosomes The genetic blueprint for the cell is carried by DNA, which is a polymer of just four repeating chemicals called nucleotides. The four nucleotides are each composed of unique nitrogen bases (adenine, cytosine, guanine and thymine) and common triphosphate and deoxyribose sugar moieties. The sugar and phosphate groups are linked to one another by phosphodiester bonds to form a DNA molecule. It is the order in which the nucleotides are incorporated into the DNA chain that carries the information. Despite having only four ‘letters’, this genetic ‘alphabet’ is sufficient to describe all the ‘recipes’ necessary to make and maintain a complex organism with thousands of different proteins. Chromosomes are made from two strands of DNA, intertwined to produce a double helix (Fig. 3.4.1 Only gold members can continue reading. Log In or Register to continue Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window)Like this:Like Loading... Related Related posts: Kinases and phosphatases in cell signalling Ion pumps and ion exchangers Electrical conduction in nerves Proteins and protein function Stay updated, free articles. Join our Telegram channel Join Tags: The Flesh and Bones of Medical Cell Biology Jun 18, 2016 | Posted by admin in BIOCHEMISTRY | Comments Off on DNA and gene transcription Full access? Get Clinical Tree
4 DNA and gene transcription Questions How is genetic information stored in the cell? What is the structure of DNA? How is gene expression controlled? DNA and the chromosomes The genetic blueprint for the cell is carried by DNA, which is a polymer of just four repeating chemicals called nucleotides. The four nucleotides are each composed of unique nitrogen bases (adenine, cytosine, guanine and thymine) and common triphosphate and deoxyribose sugar moieties. The sugar and phosphate groups are linked to one another by phosphodiester bonds to form a DNA molecule. It is the order in which the nucleotides are incorporated into the DNA chain that carries the information. Despite having only four ‘letters’, this genetic ‘alphabet’ is sufficient to describe all the ‘recipes’ necessary to make and maintain a complex organism with thousands of different proteins. Chromosomes are made from two strands of DNA, intertwined to produce a double helix (Fig. 3.4.1 Only gold members can continue reading. Log In or Register to continue Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window)Like this:Like Loading... Related Related posts: Kinases and phosphatases in cell signalling Ion pumps and ion exchangers Electrical conduction in nerves Proteins and protein function Stay updated, free articles. Join our Telegram channel Join Tags: The Flesh and Bones of Medical Cell Biology Jun 18, 2016 | Posted by admin in BIOCHEMISTRY | Comments Off on DNA and gene transcription Full access? Get Clinical Tree
