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Life, taken apart.

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AP Biology

8 chapters
No. 0113 pages

Chemistry of life

the molecules that make it go Water molecules, red oxygen and white hydrogens, linked by blue hydrogen bonds, with partial charges marked on one molecule
No. 0212 pages

Cell structure and function

compartments and membranes A cut-away animal cell: the nucleus wrapped in ribosome-studded rough ER, a Golgi stack, red mitochondria, lysosomes and blue transport vesicles inside the plasma membrane
No. 0311 pages

Cellular energetics

enzymes, light and respiration A chloroplast and a mitochondrion side by side, with glucose and O₂ flowing from one to the other above and CO₂ and H₂O flowing back below, light arrows striking the chloroplast and ATP rising from the mitochondrion
No. 0411 pages

Cell communication and the cell cycle

signals, and the division they trigger A cell membrane with a receptor holding a red signal molecule; below it, cAMP spills from adenylyl cyclase and a branching cascade of kinases lights up red, one, three, nine, then twenty-seven target enzymes
No. 0514 pages

Heredity

meiosis and Mendel Four haploid cells after meiosis, each with one long and one short chromosome in a mix of red (maternal) and blue (paternal)
No. 069 pages

Gene expression and regulation

from DNA to protein A paper-white DNA double helix with red, blue and black base pairs, labelled 5′ and 3′, above a single wavy strand of RNA
No. 0713 pages

Natural selection

populations, changing Moths resting on a soot-darkened tree trunk, most of them now dark, beside a graph of the dark fraction rising over generations
No. 0810 pages

Ecology

energy and populations in communities A stepped pyramid of white cubes, each a tenth the volume of the one below, with sunlight arrows striking the base and red beads of heat drifting off each level