Prokaryotic Cells.

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-Evolved earlier than Eukaryotic cells.

-Smaller and simpler than Eukaryotic cells as don't have a nucleus/membrane-bound organelles.

~70s Ribosomes, Slime Capsule, nucleoid, cell wall, cell membrane, mesosomes, plasmids, flagella

CYTOPLASM

~[S] No membrane bound organelles, Contains dissolved substances and enzymes.

~[F] Cytoskeleton=present, but composed of diff proteins than Eukaryotic cytoskeleton.

Ribosomes

~[S] Smaller 70s Ribosomes

~[F] Synthesise proteins.

Circular DNA

~[S] Single molecule of circular DNA, NOT ASSOCIATED with Histone proteins, Located in the Nucleoid, No Nucleus.

~[F] Contains the genetic information for the replication of bacterial cells.

Cell Wall

~[S] Made of Murein (peptidoglycan), polymer of polysaccharides and peptides (glycoproteins).

~[F] Physical Barrier that Excludes certain substances. Protects against: Mechanical Damage, Osmotic lysis.

Plasmid

~[S] Small, circular, double-stranded DNA molecules found in the cytoplasm. Separate from main DNA strand.

~[F] Contain genes which may aid the survival of bacteria in adverse conditions, e.g. produce enzymes which break down enzymes. These genes=passed from one bacterial cell to another during conjugation, where bacterial cells exchange genes.

Capsule

~[S] Mucilaginous slime layer.

protects bacteria from other cells

helps groups of bacteria stick together for protection

prevents the cell from drying out.

flagellum

Composed of a protein: tubulin

Diff interna; structure to flagella in Eukaryotes

Cell surface membrane:

Pili

shorter and straighter than flagella. HAIR LIKE STRUCTURES

Some bacteria have one or more flagella

used to move cells (motile)