Summary of DNA Structure and Replication: Crash Course Biology #10

00:00:00 - 00:10:00

DNA is a molecule that stores genetic information and is responsible for the assembly of proteins. The human chromosome 1 contains a single DNA molecule with 247 base pairs. To copy DNA, the cell uses a process called replication. The leading strand is always used as a reference, and the cell can use it to build new copies of the DNA.

• 00:00:00 DNA is a molecule that stores genetic instructions, and is responsible for the assembly instructions for everything that a person is. It is made of a sugar and phosphate molecule, and is linked together by nitrogen bases. Each nucleotide has a specific base sequence, and this sequence allows for the creation of proteins. The human chromosome 1 contains a single DNA molecule with 247 million base pairs.
• 00:05:00 DNA is a long molecule made up of nucleotide bases. Nucleotide bases are similar to the letters in a sentence, and when paired together, they form a code that tells the cell what to do. The code is read from the top to the bottom, and each nucleotide base corresponds to a specific amino acid. To copy DNA, the cell uses a process called replication. First, the cell separates the DNA into two strands. One strand is the leading strand, and the other is the lagging strand. The leading strand is the "good" strand, and the lagging strand is the "scumbag" strand. The cell uses the lagging strand as a template to create two new strands, which go in opposite directions. The leading strand is always used as a reference, and the cell can use it to build new copies of the DNA.
• 00:10:00 DNA replication is a process by which the genetic information in a cell is copied from one strand to another. DNA polymerase, an enzyme, adds matching nucleotides to the main stem of the molecule at the beginning of the replication process, and RNA primase lays down occasional short RNA primers. Okazaki fragments, created by RNA primase, serve as starting points for DNA polymerase to work backwards along the strand. DNA ligase joins the fragments together.