1. Výukový materiál MB 04 - 94 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 2014 CELL DIVISION

2. entire cell = zygote • zygote divides repeatedly • developed cell differentiates > tissues > organs> organisms CELL DIVISION

3. cells reproduce by division • division is anticipated by chromosome division = replication of DNA PROKARYOTIC CELL DIVISION

4. the life period of the cell from its origin up to the development of daughter cells • the cell stops dividing > it accomplishes specific functions • liver cell divides once a year • neuron never divides • the most cells of human body undergo about 50 divisions and then they die CELL CYCLE

5. cell cycle - 2 main phases: 1) cell division • nuclear division: mitosis or meiosis • cell division 2) interphase • 90% of whole cell cycle • the cell grows up • in the nucleus there is chromatin > replication of DNA • interphase: G1, S, G2 phase CELL CYCLE

6. CELL CYCLE

7. replication of DNA • cell division • cell cycle: • sequence of processes from the first to the second division PROKARYOTIC CELL DIVISION

8. REGULATION OF CELL CYCLE

9. CHECKPOINTS • there are three of them: in the phases G1, G2, M • cells of mammals – the point in the G1 phase is obviously the most important • if the cell does not receive the signal„Ahead“ in G1 phase, it can get into G0 phase . • the most cells of our body are in this phase

10. G1 phase • metabolic activity • by the isolation of the daughter cell • the cell grows up • synthesis of RNA and proteins • main control nodal point • S phase synthetic • replications of DNA proceeds here: • DNA replicates up to double amount > chromosome is doubled since then: • created by a pair of sister chromatids • the cell is actually tetraploid INTERPHASE

11. G2 phase • relatively short • metabolic activity • the cell grows up rapidly • reduplication of organelles • formation of structures necessary for the cell division INTERPHASE

12. G0 phase • the phase when the cell does not divide any more • ending of the cell cycle • by differentiated cells • the beginning is influenced by the control nodal point • placed in the beginning G1 phase • fully differentiated cells (e.g.. neurons) do not divide any more • on the contrary e.g. liver cells - hepatocytes are able to go from G0 phase do G1 phase to start dividing again in the case of need INTERPHASE

13. it proceeds through specific compounds • either stimulated and accelerated by the division (growth hormones, cytokinins) • or, on the contrary, they inhibit, stop (lack of nutrients, cytostatics) • all regulators influence the division in G1 phase = main control nodal point REGULATION OF THE CELL CYCLE

14. Try to fill in the picture

15. 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 80-718-3268-5. • 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 80-718-2050-4 SOURCES