Transcript Prokaryotic Cell

Výukový materiál MB 04 - 90
Tvůrce: Mgr. Šárka Vopěnková
Tvůrce anglické verze: ThMgr. Ing. Jiří Foller
Projekt: S anglickým jazykem do dalších předmětů
Registrační číslo: CZ.1.07/1.1.36/03.0005
Tento projekt je spolufinancován ESF a SR ČR
PROKARYOTIC CELL
2014
PROKARYOTIC CELL



created by only one
unseparated part
(compartment)
the compartment is
enclosed with the
plasmatic membrane
the compartment is
filled with the cytosol
PROKARYOTIC CELL




the nucleus of the
prokaryotic cell :
not enclosed with
nuclear membrane
it contains only
double helix circular
DNA = nucleotid
circular DNA
represents only
circular chromosome
PROKARYOTIC CELL
the cell reproduces by transverse partitioning
> into two daughter cells
 the cell is covered with cell wall:
 the main element of the cell wall is
peptidoglycan
 in the cytosol there are ribosomes – the
synthesis of proteins is proceeded here
 one or more flagella > hollow screw-shaped
threads

PROKARYOTIC CELL
a simple type of the cell
 prokaryota are unicellular organisms
(bacteria, cyanophyta, mycoplasmata)
 size: 1-2 µm
 cytoplasm poor in membrane organelles
 only photosynthesis doing cyanophyta have
biomembranes = thylakoids
 they create neither differentiated tissues nor
textures

PROKARYOTIC CELL








plentiful ribosomes > several thousands in a cell
prokaryotic ribosomes are smaller than eukaryotic
ribosomes
cell inclusions are frequent here
they have not got miotic apparatus (partitioning
spindles)
they have not got mitochondria !
material store:
acid beta-hydroxybutyric, glycogen and volutin
they reproduce asexually, by transverse division
PROKARYOTIC CELL






4 always present
structures:
NUCLEOID
ribosomes
cytoplasmic membrane
cell wall
+ cytoplasm
NUCLEOID








core equivalent
not enclosed by any covering
laid loosely in the cytosol
prokaryotic chromosome is 1000 times longer
organized in loops
one chromosome = one DNA >> genes pass in the
unchanged form into the daughter cells
haploid prokaryotic cells
circular = cyclic >> it has not got free endings
PLASMIDS





small circular, double helix
DNA molecules = plasmids
they carry additional, not
necessary information
they penetrate excellently
through the membrane and
pass from one cell into
another = bearers of new
genes into a cell (use in
genetic engineering)
they can sometimes bear
enormously important
genetic information (e.g.
gene for resistance against
antibiotics)
they bear genes enabling
the conjugations of bacteria
CYTOPLASMIC MEMBRANE







function :
it separates the only part of the cell
it releases energy from organic substances!!!!
it isolates internal environment from the external
it is semipermeable
smooth but it also makes spurs = invagination of
the membrane – on those grooves respiratory
chain
green bacteria have bacteriochlorophyll here
CELL WALL



the only tight structure of the prokaryotic cell
it consists of peptidoglycan
above the wall there can also be a casing from
proteins or polysaccharides
CYTOPLASM
very viscous
 concentrated solution
 cytoplasm is not divided into compartments
 it misses organelles typical for eucaryotic
cells

FLAGELLUM
different from eukaryotic flagellum in both the
composition and in the function
 a hollow formation
 protein flagellin
 it is anchored in the cytoplasmic membrane
and cell wall – > rotary movement of the
flagellum
 energy for the movement of the flagellum without ATP !!!!

WHAT KIND OF ORGANELLE IS THIS ?
PRACTISING DESCRIPTION OF PROKARIOTIC CELL
DESCRIBE THE PROKARYOTIC CELL
SOURCES





KUBIŠTA, Václav. Obecná biologie. Praha: Fortuna, 2000, ISBN 80-7168-714-6.
CHALUPOVÁ - KARLOVÁ, Vlastimila. Obecná biologie. Olomouc: Nakladatelství Olomouc,
2010, ISBN 978-80-7182-282-0.
ZÁVODSKÁ, Radka. Biologie buněk. Praha: Scientia, 2006, ISBN 80-86960-15-3.
ROSYPAL, Stanislav. Nový přehled biologie. 1. vyd. Praha: Scientia, 2003, 797 s. ISBN 80-7183268-5.
JELÍNEK, Jan, Vladimír ZICHÁČEK a Miroslav ŠVÁTORA. Biologie pro gymnázia: teoretická a
praktická část. 2. dopl. a rozš. vyd. Olomouc: Nakladatelství Olomouc, 1998, 551 s. ISBN 80718-2050-4