Download Cell: • Small, membrane-enclosed unit • Filled with a concentrated

Cell:
• Small, membrane-enclosed unit
• Filled with a concentrated aqueous solution of chemicals
• Ability to create copies of themselves by growing and dividing in
two.
• The simplest forms of life
Feature
Size
inner membranes
skeleton
connections
Differentiation
Semiautomic organelles
Procaryiotes
1-10m
no
106
circular
plasmamembrane
dependent
no
external
no
no
no
Apoptosis
not sure
Nucleus
DNA size
DNA organization
Cell division
Eukaryotes
5-100m
yes
107-109
linear, histons
microtubulusdependent
yes
internal 3 types
yes
yes
chloroplastis,
mitochondria
yes
Plant and animal cells:
Organellum
Plant cell
Animal cell
cellmembrane+wall
cellmembrane
Plasmamembrane
yes
Nucleus
yes
Cytoplasma
RER and SER
Endoplasmatic
Reticulum
Free and RER-assotiated
Ribosoma
ATP production
Mitocondrium
Golgi apparatus
Vacuolum
Cytosceleton
Synthesis of membrane proteins secretory proteins,
polysaccharids
Central: water, turgor
One or a few: water, ions
pressure, similar function to unused compounds
animal lisosomes
Microtubuli intermedier filaments, microfilaments
Organellum
Centrosoma
Plastis
Lisosoma
Peroxisoma
Plant cell
Animal cell
no
yes
yes
no
rarely
yes
Fatty acids to glucose helps Protection of the cells from
photorespiration
free radicals
From Golgi
Secretory vesuculi
flagella
rare
Cilia
yes
typical
Electronmicroscipic picture of a plant cell
http://www.oncoursesystems.com/school/webpage/10845583/788307
Chemical bonds:
• covalent bond:
it is formed when two atoms share a pair of electrons
• ionic bond:
it is formed when electrons are donated by one atom to another
Weak chemical bonds:
short-range attractive forces
• van der Waals attractions,
• electrostatic attractions,
• hydrogen bonds:
H atom is “sandwiched” between two electron-attracting atoms
Chemical composition:
Membranes: fatty acids
phospholipides, cholesterol:
Cell surface compounds, stored nutrients: carbohydrates:
monosaccharides, polysaccharides
Enzymes, secretory materials, cytosceleton: proteins:
amino acids
Genome: DNA
Protein synthesis, regulation: RNA
Energy storage: ATP nucleotide phosphates