Search results for: 'Okazaki fragments'

Watch Later 1:08

Replication of DNA and Chromosomes/ How do cells replicate their DNA? (Animation) no Audio

By: HWC, Views: 7460

DNA replication in E. coil begins at a site called oriC where a replication bubble forms. At either end of this bubble is a replication fork. Since DNA polymerase Ill can read its DNA template strand only in the 3' to 5' direction this means that one strand (leading) can be read continuously b...

Watch Later 2:43

The Lagging Strand in DNA Replication and Replication in Action

By: HWC, Views: 7216

The lagging strand is the strand of nascent DNA whose direction of synthesis is opposite to the direction of the growing replication fork. DNA backbones run in opposite directions, the strands in a DNA molecule are oriented antiparallel to one another. New DNA is made by enzymes called DNA...

Watch Later 3:03

Semidiscontinuous DNA replication

By: HWC, Views: 7335

During DNA replication, one of the two DNA strands, the leading strand, is replicated continuously, or all at once, in the 5' to 3' direction. The other strand, called the lagging strand, is replicated discontinuously, or in pieces, in the 3' to 5' direction. This is necessary because DNA poly...

Watch Later 3:50

New DNA Strand Replication

By: HWC, Views: 7119

First step: strands are separated • Helicase unwinds the DNA double helix at the replication fork • SSBs coat the single strands to prevent reannealing • Polymerase attaches nucleotide at 3' end • Synthesis is in 5' to 3' direction DNA Polymerase: • Only extends nucleic ac...

Watch Later 1:01

DNA fingerprinting Animation

By: HWC, Views: 4674

DNA fingerprinting enables a scientist to compare the DNA from two biological samples, such as a blood stain and a suspect's blood. A restriction enzyme is added to the samples to be compared. The enzyme cuts the DNA into smaller fragments. The DNA fragments are placed on an electrophor...

Watch Later 2:23

Hierarchical Sequencing Method - Sequence Tagged Sites

By: HWC, Views: 6961

In the hierarchical sequencing method, researchers begin by collecting cells. In humans, each cell contains 23 pairs of chromo-somes. Here we specifically track the DNA from just one of the 23 pairs. Chromosomes have a series of unique DNA sequences, called sequence-tagged sites (STSs), that a...

Watch Later 1:37

DNA Sequences - Dideoxy Sequencing

By: HWC, Views: 7042

A short, radiolabeled primer is annealed to the single-stranded DNA to be sequenced. The DNA serves as a template for in vitro DNA synthesis. The DNA-primer mixture is split into four separate tubes. DNA polymerase and a solution of dNTPs are added to each tube. One of the four 2',3' dideoxy-N...

Watch Later 1:29

Fertilization and Development

By: HWC, Views: 8073

• Fertilization is the process by which the two gametes from the parents fuse their genetic material to form a new individual (zygote). • Fertilization requires that sperm cells swimming through the uterine tube contact a secondary oocyte. • Once sperm penetrate the secondary oocyte's ...

Watch Later 1:20

Carbohydrate digestion - mouth and stomach & pancreas and small intestine

By: HWC, Views: 7485

• Digestion of complex carbohydrates (starches and glycogen) involves: • Amylases produced by the salivary glands and pancreas. • Brush-border enzymes in small intestine. • In the mouth, amylase from the parotid and submandibular salivary glands begins carbohydrate digestion. �...

Search Results