Prokaryotic Cell Structure (+vs Eukaryotes) Flashcards
Give the differences between prokaryotes and eukaryotes
P: single called organisms eg bacteria & archaea
E: more complex cells eg animals, plants & fungi
P: no nucleus-> circular loop of DNA in the cytoplasm, no introns, no proteins/histores/chromosomes
E: nucleus present
P: no membrane bound organelles-> always give two examples
E: Membrane bound organelles-> mitochondria/chloroplasts (plants), Golgi apparatus, rough Endoplasmic reticulum
P: small ribosomes (70S)
E: large/big ribosomes (80S)
P: cell wall -> peptidoglycan (glycoprotein)
E: animals-> cell walls absent
Plants-> cellulose
Fungi-> chitin
P: plasmids present (all)
E: plasmids absent
P: capsule (some)
E: capsule absent
List the structure of prokaryotic cells
Loop of DNA
Cytoplasm
Small ribosome
Cell membrane
Cell wall
Slime capsule
Flagella
Plasmids
Loop of DNA
No nucleus , DNA is free in the cytoplasm
Cytoplasm
Reactions take place (all)
Small ribosomes
- make proteins
- made from proteins and mRNA
Cell membrane
(All) controls what goes in and out
Cell wall
(All) -made from peptidoglycan
- gives strength and structure
Slime capsule
- extra protection slime layer
- adds extra protection
Flagella
Rotates to move the cell
Plasmids
(Some)
- small loops of DNA
- can be passed between bacteria
- can Carry useful genes eg antibiotic resistance
Prokaryotic have no membrane bound organelles aka,….
- nucleus
- Golgi
- ER
- lysosomes
- mitochondria
- chloroplasts
Size of prokaryotic vs eukaryotic cells
Bacterial = 1-10ym long
Eukaryotic = 8-100ym
Whats the flagellum called on a sperm cell
Undulipodium (undulate meaning waves like a tail) ONLY ON SPERM CELL
Infolding plasma membrane
May form a photosynthetic membrane or carry out nitrogen fixation
Mesosomes
Infolding of plasma membrane associated w DNA during cell division and helps w formation of new. Cell walls
What is the plasma membrane made of?
The phospholipid bilayer
Explain binary fission
Bacteria reproduce by binary fission. Their chromosome (loop of DNA) and any plasmids they may have, are replicated before cell separation.
This process is faster than the cell cycle of eukaryotic cells so bacteria are able to reproduce much more quickly.
In optimum conditions binary fission can occur every 20 minutes
