Quiz 1: Reading Info Flashcards
Cytoplasm
aqueous internal solution and suspended particles
Cytosol
just aqueous solution
Metabolite
intermediated in biosynthetic and degradation pathways
What limits cellular dimensions?
lower limit of size set by minimum number of biomolecules required by the cell
upper limit of size is set by the rate of diffusion: need a high surface-to-volume ratio for diffusion to occur
Are eukaryotes more closely related to bacteria or archaea?
Archaea
Share closer common ancestor
Types of single cell organisms
Archaea- extreme environments
Bacteria- soils, surface waters, tissues of other organisms
What organelles do all cells have?
cytoplasm, plasma membrane, ribosomes
What types of cells have a nucleoid?
Bacterial cell
Do bacteria cells have membrane bound organelles?
No
Cell envelope
the plasma membrane and the layers outside of it
differ in bacteria cells (gram+, gram-, etc.)
Gram positive bacteria
have a thick layer of peptidoglycan outside their plasma membrane but lack an outer membrane
Gram negative bacteria
have an outer membrane composed of a lipid bilayer
the cell wall is wedged between 2 membranes
What is in the outer membrane of gram negative bacteria?
1) porins: provide transmembrane channels for low molecular weight compounds and ions to diffuse
2) lipopolysacchrides
Do archaea have cell walls?
yes, normally made of peptidoglycan or hard protein
plasmids
small circular segments of DNA in the cytoplasm of bacteria
outside of the main DNA in the nucleoid
What gave the first hints that bacteria and archaea constitute different domains?
ribosomal differences
Size difference between eukaryotic cells and bacteria/archaea cells
5-100µm for eukaryotic cells
2µm for prokaryotic cells (less stuff to contain)
Mitochondria
site of most of the energy extracting reactions of the cell
Golgi complex
postmaster of the cell
processes, packages, and targets proteins to other organelles for export
Rough endoplasmic reticulum
site of much protein synthesis
Smooth endoplasmic reticulum
site of lipid synthesis and drug metabolism
Peroxisomes
oxidize fatty acids (breakdown fatty acids)
Lysosomes
filled with digestive enzymes to degrade unneeded cellular debris
vacuoles
store large quantities of organic acids
*large central vacuole found in plant cells