All notes · HSC

1 chapter · 24 notes · all free

1. The Cell, Cytology and Cell TheoryWhat did Hooke see in cork, living cells or dead? Many students get it wrong.
2. Kinds of Cells and Their Measurement70S or 80S? Can you tell a prokaryotic cell from a eukaryotic one?
3. The Cell WallAnimal cells lack it, plant cells have it: can you say what each layer of the cell wall is made of?
4. Protoplast, Protoplasm and Non-living Cell ContentsIs chlorophyll a reserve material? Which parts of a cell are living, and which are not?
5. Plasma Membrane (Cell Membrane)A film this thin decides what enters a cell. How long did scientists take to draw it right?
6. Cytoplasm and Endoplasmic ReticulumGrainy means protein, smooth means lipid. How do you keep rough and smooth ER apart?
7. RibosomeAn antibiotic kills bacteria but leaves your own cells alone. Why?
8. Golgi Body and LysosomeWho is the cell's traffic police, and who is its suicide bag? Can you tell them apart?
9. MitochondriaThe cell's power house has a shield outside and a factory inside. Which membrane does what?
10. PlastidsA carrot grows underground, so why is it orange? Learn the three plastids once and for all.
11. Centriole and CytoskeletonA cell has no bones, yet it holds its shape and moves. How?
12. Peroxisome, Glyoxisome and VacuoleWhat breaks down the cell's poison, and how does seed fat become sugar?
13. The NucleusRed blood cells have no nucleus, yet it is called the brain of the cell. What is inside it?
14. The Chromosome: Discovery, Number and StructureHumans have 46, a fruit fly has 8. Can you recall the number for each organism?
15. Types, Composition and Functions of ChromosomesA chromosome can look like a V, L, J or I. What decides the shape?
16. Nucleic Acids and Their ComponentsCan you tell a nucleoside from a nucleotide? See how base, sugar and phosphate join, step by step.
17. DNA: Structure, the Watson-Crick Model and FunctionsAcross the two strands, why is A always facing T? The answer is one measurement.
18. RNAWho carries DNA's instructions to the ribosome? The jobs of tRNA, rRNA and mRNA in one note.
19. DNA ReplicationHow does one double helix become two, and why is one new strand built in pieces?
20. TranscriptionDNA never leaves the nucleus, so how does the message for a protein reach the cytoplasm?
21. TranslationHow does the information in DNA become protein? tRNA enters at A, joins at P, and then?
22. Gene and GenomeHow much of the human genome actually does the work? And what is the rest?
23. Operon and Gene ExpressionHow does a bacterium know which genes to switch on, and when?
24. Genetic Code and the Role of DNAHow do four letters make 64 codons, and which one starts and which ones stop?

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