cells Flashcards
cell theory
cells are fundamental units of life
all organisms are composed of cells
all cells come from pre existing cells
modern cells evolve from common ancestor
prokaryotes v eukaryotes
DNA in nucleoid v DNA in nucleus
no membrane bound organelles v does have
peptidoglycan cell wall v cellulose etc cell wall
DNA circular v DNA linear
Binary fission v mitosis/meiosis
nucleus
command centre of cell
double membrane/nuclear membrane
nuclear/annular pores - mRNA goes in and out
nucleolus = ribosomal genes
DNA in long strands covered w/ histones = chromosomes
RNA transcribed from DNA leaves pores and translated in cytoplasm
mitochondria
double membrane (endosymbiosis)
highly convoluted inner membrane - inner projections = cristae
carry out aerobic cellular respiration - ATP=stores energy
chloroplasts
double membrane (endosymbiosis)
has thylakoids
photosynthesis
RER
membrane tubes and flattened sacs which make and package various cellular components eg proteins and lipids
ribosome
2 subunits which come together in presence of mRNA
synthesis aa chains
lysosome
Recyling bin of cell
highly acidic interior
digestive enzymes
hydrolyse macromolecules into monomers
vacuole
plant equivalent of lysosome
used for storage and maintaining water balance
peroxisomes
another type of recycling bin
convert toxic peroxides into water
golgi apparatus
folded membrane structure
collecting, processing and distributing materials for export from cell (in secretory vesicles)
endomembrane
system of compartments that incl all membrane bound components of cell except mitochondria, chloroplasts and microbodies
plasma membrane
controls in and outs of cell
cytosol
space b/w organelles
watery-gel many biochemical processes occur there
cytoskeleton
collection of proteins in cytosol that act as scaffolds and structural support in cell
microtubule
largest
made of tublin dimer
maintain shape (girders)
move chromosomes in mitosis
move organelles
cilia, flagella
microfilaments
smallest
made of actin
maintain shape (tension bearing)
changes in cell shape
muscle contraction
cytoplasmic streaming
pseudopodia
cleavage furrow formation during division
intermediate filaments
medium sixed
made of keratin protein
maintain shape (tension bearing)
anchor nucleus
anchor some other organelles
formation of nuclear lamina
