Class LX (Seience) NOTES
CELL
Cell is the fundamental, siructural and functional unit of iiving
Grgmsus.
History:
LRobert Hooke (1¬65) discovered cell in cork (a substance which from bark
of a tree) chrough seif-designed miroscope
2.Leeuwenhoek (1674) discorsrd free living cells in pond water.
3.Robert Brown (1831) disce-ered nucleus in cell.
4.Purkinje (1839) coined the term protoplasm field substance of cell.
5.Virchow (1855) All cell arise from pre-existing cells
6Schleiden and Schwann (1838-1839) gave ce!l theory.
Cell -Theory -
1.Allorganisms are made up of cells.
2.Allmetabolic activities take place in cell.
3.Every organism starts its life as a single cell.
Rudolf Vichow---All cells arisefrom pre -existing cell only.
, Shape of cells :
shape (eg.most plant and animal cells ),while some cells lik.
Some cells have tixed
WBC,
shape
and amoeba keep changing theit
1.Spherical (e g. ovum)
2.Spindle (eg.Smooth muscle cell )
J.discoidal (eg. RBC)
4.Elongated (eg. nerve cell)
Red Blood Cell
Diagraan
Top View oi Red Biood Cell
iadent iemogisbit- rich
Cvtoplast:
- Eiconcave Shape
Size of ceils.
Smallest cell -’ Mycoplasma
Large egg celi ’ Ostrich egg
Longest nerve cell ’ Nerve cel!
Prokarvotic Cell:
Cel! size is small (1-10 um)
Nucleus is absent (Nuclear membrane is not present calied
nucleoid)
º Contain single chromosome
Cell division takes place by fission or budding.eg. bacteria .blue gveo
algae ete.
CELL
Cell is the fundamental, siructural and functional unit of iiving
Grgmsus.
History:
LRobert Hooke (1¬65) discovered cell in cork (a substance which from bark
of a tree) chrough seif-designed miroscope
2.Leeuwenhoek (1674) discorsrd free living cells in pond water.
3.Robert Brown (1831) disce-ered nucleus in cell.
4.Purkinje (1839) coined the term protoplasm field substance of cell.
5.Virchow (1855) All cell arise from pre-existing cells
6Schleiden and Schwann (1838-1839) gave ce!l theory.
Cell -Theory -
1.Allorganisms are made up of cells.
2.Allmetabolic activities take place in cell.
3.Every organism starts its life as a single cell.
Rudolf Vichow---All cells arisefrom pre -existing cell only.
, Shape of cells :
shape (eg.most plant and animal cells ),while some cells lik.
Some cells have tixed
WBC,
shape
and amoeba keep changing theit
1.Spherical (e g. ovum)
2.Spindle (eg.Smooth muscle cell )
J.discoidal (eg. RBC)
4.Elongated (eg. nerve cell)
Red Blood Cell
Diagraan
Top View oi Red Biood Cell
iadent iemogisbit- rich
Cvtoplast:
- Eiconcave Shape
Size of ceils.
Smallest cell -’ Mycoplasma
Large egg celi ’ Ostrich egg
Longest nerve cell ’ Nerve cel!
Prokarvotic Cell:
Cel! size is small (1-10 um)
Nucleus is absent (Nuclear membrane is not present calied
nucleoid)
º Contain single chromosome
Cell division takes place by fission or budding.eg. bacteria .blue gveo
algae ete.
