basic Flashcards
chemistry going on in cell
- Needs to import food and gases
- Needs to control changes in pH and temperature generated by reactions.
- Deal with waste products
Prokaryotes
No clear nuclear structure
Unicellular
1 - 10 um
Eukaryotes
Defined nucleus present
Unicellular but commonly multicellular
10 - 100 um
Light microscope
1 mm - 100 nm
Millimetres
Micrometres
Nanometres
10^-3 [mm]
10^-6 [um]
10^-9 [nm]
Electron microscope
100 um - 1 nm
Compartmentalisation
in eukaryotes
organisation in eukaryotic cells increase surface area for the chemical reactions occur more efficiently
~ Organised by function
~ Organelles - little organs Eg., nucleus
~ Cell divided by boundaries = Membranes
Outer membrane - plasma membrane & further complex membrane structures within the cell
All organelles surrounded by membranes
Membranes
Composed of amphipathic phospholipids
Monolayer/ Bilayer
Energetically favourable, form spontaneously
Nucleus
1-3 mm
Site of cellular DNA storage, replication and transcription.
DNA packaged into________
nucleus
Chromosomes ~ 10^8 nucleotides in length
DNA plus histone proteins form chromatin
Rough endoplasmic reticulum
Associated with nucleus
Site of translation of proteins destined for membranes or secretion
Smooth Endoplasmic reticulum
No ribosomes
Involved in:
Carbohydrate metabolism
Drug metabolism
Ion movements
Transport vesicles bud off the ____and migrate to the ______
Endoplasmic reticulum
Golgi apparatus [cis face- recieving site; trans face - shipping site] [ with cisternae at the end]
The main cytoskeletal elements
microtubule
microfilaments
__________
Peroxisomes
Contain oxidative enzymes that produce hydrogen peroxide as a toxic by-product which they then inactivate with catalase.
