1.WAT IS A CELL??

LIVING THINGS ARE MADE UP OF TINY UNITS CALLED CELLS.

CELLS ARE THE SMALLEST LIVING UNITS IN A LIVING

THING,

• SOME LIVING THINGS ARE MADE UP OF A SINGLE CELL . THEY ARE UNICELLULAR.

• OTHER LIVING THINGS ARE MADE UP OF MANY CELLS. THEY ARE MULTICELLULAR.

2.WHAT ARE CELLS LIKE ??

CELLS DIFFER IN SHAPE AND SIZE.

3.PARTS OF A CELL.

CELLS HAVE3 DIFFERENT

PARTS.

MEMBRANE:IS THE

COVERINGAROUND THE

CELL.

NUCLEUS:IS THE PART

WHICH CONTROLS THE

CELL.

CYTOPLASM:IS BETWEEN

THE NUCLEUSAND THE

MEMBRANE.

• PLANT CELLS ALSO HAVE A HARD CELL WALL AROUND THE

MEMBRANE.

THIS IS WHY SOME PLANT STEMS ARE HARD.

1.HOW ARE LIVING THINGS ORGANISED??

• MULTICELLULAR LIVING THINGS HAVE THE FOLLOWING STRUCTURE.

• CELLS FORM TISSUES: TISSUES , ARE MADE UP OF CELLS WHICH WORK TOGETHER.

• TISSUES FORM ORGANS: ORGANS ARE MADE UP OF CELLS WHICH WORK TOGETHER.

• ORGANS FORM SYSTEMS: SYSTEMS ARE MADE UP OF ORGANS WHICH WORK TOGETHER.

• AN ORGANISM IS A COMPLETE

LIVING THING: SYSTEMS WORK TOGETHERIN A

ORGANISM. ALL LIVING THINGS ARE ORGANISMS. ALL THE SYSTEMS WORK TOGHETHER TO KEEP A LIVING THING HEALTY.

SOME PICTURES:

• The tissue

• MUSCLE CELLS.

INFORMATION:

• CELLS ARE THE FUNDAMENTAL UNITS MORPHOLOGICAL,PHYSIOLOGICAL AND BREEDING OF ALL LIVING THINGS.

• THE CELLS ARE PROKARYOTES OR EUKARYOTES.

• EUKARYOTES CELLS ARE

CHARACTERIZED BY THEIR GENETIC MATERIAL ENCLUDED IN A SEPARATE NUCLEUS OF THE CYTOPLASM BY A MEMBRANE.

• PROCARYOTES ARE THE SIMPLEST.THEIR GENETIC MATERIAL IS IN THE DIREC CONTAC WITH THE CYTOPLASM.

• THERE ARE 2 TYPES OF EUKARIOTIC CELLS:ANIMALS AND PLANTS.

• BOUTH HAVE IN COMUN THE GOLGI APPARATUS ,THE NUCLEUS AND THE ENDOPLASMATIC RETICULUM AMONG OTHERS.

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