CELLS BIO SL Y1

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3 rules of cell theory

composed of 1 or more cells, basic unit of structure and organization, come from pre - existing cells

electron microscopy

high resolution and magnification so can reveal ultrastructure in cells

freeze fracture microscopy

splits membranes along lipid bilayer allowing direct observation of membrane proteins

cryo EM

samples are frozen rapidly preserving them in a near - native state

fluorescent/immunofluorescent stains

uses antibodies attatched to fluorescent dyes which allows precise location

all cells have

plasma membrane, cytoplasm, DNA

prokaryotes have

cell wall, plasma membrane, naked loop DNA, 70s ribosomes

eukaryotes have

plasma membrane, compartamentalized cytoplasm, nucleus, membrane bound organelles, 80s ribosomes

8 functions of life

Homeostasis, metabolism, nutrition, movement, excretion, growth, response to stimuli, reproduce genetically similar offspring

fungi has

no plastids, has chintin walls, large permanent vacuole, has centrioles and undulipodia in fungi with swimming male gametes

plant has

plastids like chloroplasts, cellulose walls, large permanent vacuole, has centrioles and undulipodia in fungi with swimming male gametes

animal has

no plastids, no wall, small temporary vacuole, has centrioles, has cillia and flagella

cell theory exceptions

aseptate fungal hyphae - many nuclei within cytoplasm, skeletal muscle fibres - multinucleated 4 protein, red blood cells - no nucleus, phloem sieve tube elements - lose nucleus at maturity