Basic Processes
Class 11 · Biotechnology
4 ideas in Class 11 Biotechnology, explained in plain words, with games and quizzes to practise.
DNA Is the Genetic Material
Part of: Proof Molecule
Miescher 1869 isolated nuclein before Griffith 1928 moved traits via heat-treated extracts, Avery 1944 fingered DNA when only DNase stopped change, Hershey-Chase 1952 traced phosphorus into pellets, and Chargaff equalities crowned DNA.
Why it matters. Experiment logic plus year order answers proof questions.
Key words
- Nuclein
- : Miescher's nuclear substance.
- Transformation
- : Genetic transfer between cells.
- DNase
- : DNA-destroying enzyme.
- Bacteriophage
- : Bacteria-infecting virus.
- Chargaff rule
- : A equals T, G equals C.
Try it in two minutes
- Date 1869 to 1952.
- Digest with DNase only.
- Trace phosphorus inside.
Try at home. Explain why sulphur stayed outside cells.
Genes Packed and Copied
Part of: Proof Molecule
Bacterial DNA coils with HLU and plasmids, eukaryotes wrap 146 base pairs around an H2A-H2B-H3-H4 octamer with H1 on the linker, humans hold 3000 megabases with 20000 genes, and Meselson-Stahl 1958 proved one-old-one-new copying by polymerase III, primase and ligase.
Why it matters. Packing, enzymes and leading-lagging logic answer flow questions.
Key words
- Nucleosome
- : DNA plus histone spool.
- Histone
- : Basic DNA-wrapping protein.
- Genome
- : Full DNA set.
- Okazaki fragment
- : Lagging-strand short piece.
- Ligase
- : Nick-sealing enzyme.
Try it in two minutes
- Stack 200 units.
- Copy one old strand.
- Prime then seal.
Try at home. Place origin, helicase, SSB, primer, ligase in order.
Expression and Genetic Code
Part of: Reading the Code
DNA makes RNA makes protein at 40 nucleotides per second, sigma starts and rho stops bacterial transcription, eukaryotes cap splice and tail hnRNA, triplets form 64 codons with 61 coding and stops UAA UAG UGA, ATG gives AUG, and tRNA charging plus A P E ribosome sites build chains.
Why it matters. Flow order, codon math and processing steps answer reading questions.
Key words
- Central dogma
- : DNA to RNA to protein.
- Promoter
- : Transcription start signal.
- Codon
- : Triplet coding unit.
- Anticodon
- : tRNA matching triplet.
- Wobble
- : Third-base flexibility.
Try it in two minutes
- Flow code outward.
- Start then stop.
- Decode triplets.
Try at home. Name three RNAs and their jobs.
Mutation Repair and Regulation
Part of: Reading the Code
Sickle GAG to GUG swaps glutamate for valine, transitions stay in class while transversions cross it, rare tautomers and EMS or 5-bromouracil flip pairs, BER leaves AP sites NER cuts around dimers and MMR proofreads, and Jacob-Monod 1961 lac switch fires within 2 to 3 minutes when allolactose frees the operator.
Why it matters. Change, fix and switch trio answers control questions.
Key words
- Transition
- : Same-class base swap.
- Transversion
- : Cross-class base swap.
- Mutagen
- : Mutation-causing agent.
- Operon
- : Co-controlled gene cluster.
- Repressor
- : Operator-blocking protein.
Try it in two minutes
- Swap one letter.
- Patch the damage.
- Free the switch.
Try at home. Draw lactose on versus off states.
What your child will practise
- DNA Is the Genetic Material: Ocean Puzzle (Clue Puzzle)
- DNA Is the Genetic Material: Ocean Quick Fire (Quick Fire)
- Expression and Genetic Code: Jungle Puzzle (Clue Puzzle)
- Genes Packed and Copied: Space Quest (Flip and Match)
- Mutation Repair and Regulation: Desert Quick Fire (Quick Fire)
- Quiz: DNA Is the Genetic Material (8 questions)
- Quiz: Expression and Genetic Code (8 questions)
- Quiz: Genes Packed and Copied (8 questions)
- Quiz: Mutation Repair and Regulation (8 questions)