Replication and Transcription: Copying and Reading the Gene

Name: Replication and Transcription: Copying and Reading the Gene
Author: StemPy Lab

A cell must copy all of its DNA before it divides, and it must read a gene before it can make a protein. You see how Meselson and Stahl showed that each new DNA keeps one old strand. Then you meet the enzymes of replication, the leading and the lagging strand, and the way a gene is copied into RNA and finished in the nucleus. It serves the Indian syllabus (NCERT, NEET) and the matching topic of A-Level, IB and AP.

3 lessons, about 1 h 30 min3 simulations11 problems3 practice questionsPython in every lesson

Created by StemPy Lab

Course outline (3 lessons)

Lesson 1about 30 min
Semiconservative replication and the Meselson-Stahl experiment
Before a cell divides, all of its DNA is copied. Watson and Crick suggested that each strand is a template for a new one, and Meselson and Stahl proved it with heavy nitrogen and a density gradient. After one generation the DNA is hybrid, and after two generations half is hybrid and half is light. So replication is semiconservative.
1 simulation1 practice question1 Python program4 problems1 Python lab
Read the lesson
Lesson 2about 30 min
The machinery of replication
Copying starts at an origin of replication and goes both ways, which makes a Y-shaped replication fork. DNA polymerase uses a DNA template and the four deoxynucleoside triphosphates and adds nucleotides only in the 5 prime to 3 prime direction. So the leading strand is made in one piece, and the lagging strand is made as Okazaki fragments that DNA ligase joins.
1 simulation1 practice question1 Python program4 problems
Read the lesson
Lesson 3about 30 min
Transcription and the processing of RNA
Genetic information flows from DNA to RNA to protein. Transcription copies one strand of a gene, the template strand, into RNA, from a promoter to a terminator, with RNA polymerase. In eukaryotes the first transcript, the hnRNA, has its introns spliced out, a cap added at the 5 prime end and a tail of adenylate residues at the 3 prime end.
1 simulation1 practice question1 Python program3 problems1 Python lab1 question set1 note
Read the lesson

Test Your Learning

Replication and Transcription: Practice Paper

20 questions · 15 min

Not started

Your teacher

StemPy Lab

← Molecular Basis of Inheritance

← DNA as the Genetic Material: Experiments, Structure and Packaging The Genetic Code, Translation and Gene Regulation →

More onHeredity and Evolution › Molecular Basis of Inheritance

Discussion (0)

Loading…

Replication and Transcription: Copying and Reading the Gene

Course outline (3 lessons)

Semiconservative replication and the Meselson-Stahl experiment

The machinery of replication

Transcription and the processing of RNA

Test Your Learning

Your teacher

1 follower

Discussion (0)

Want to go further?