The document provides an overview of cells, the basic structural and functional units of life, detailing the history of cell discovery and key figures such as Anton van Leeuwenhoek and Robert Hooke. It distinguishes between prokaryotic and eukaryotic cells, describes cell components like the nucleus, plasma membrane, mitochondria, and ribosomes, and outlines their functions. Additionally, it covers organelles such as the Golgi apparatus and lysosomes, as well as plastids specific to plant cells.

1. Cell
● Basic structural and
functional unit of all living
organisms.
● Cytology - Branch of
biology which deals with
the study of Cell.

2. Important points
● Anton van Leeuwenhoek first saw and described
a living cell.
● Robert Brown discovered nucleus .
● Robert Hooke- Introduced the term 'Cell’.
● Schleiden and Schwann - Cell Theory
● Rudolf Vichrow - Modified Cell Theory
● Largest known Cell - Unfertilised Ostrich Egg
● Smallest Cell - PPLO ( mycoplasma)
● Largest Human Cell- female ovum
● Longest Cell - Neuron

3. Types of Cell
● Prokaryotic Cell- (pro=primitive , karyos=
nucleus) Cell which do not have a nuclear
membrane and other membrane bound
organelles. Ex- Bacterial Cell
● Eukaryotic cell- (Eu = true; karyos = nucleus)cell
having well organised nuclear envelope and
several membrane bound organelle. Present in
unicellular and multicellular organisms.

4. Cell
Nucleus
Nuclear Membrane
Nucleoplasm
Nucleolus
Chromatin
Cytoplasm :
1.Cytosol
● 2.Organelle -
Mitochondria,Vacuoles
, Endoplasmic
Reticulum, Golgi
complex, lysosomes,
plastids, ribosome
Outer Membrane
Cell-wall (in Plants) and
plasma membrane

5. Nucleus
● Controlling center of cell
● Discovered by Robert
Brown
● Contains the information in
the form of nucleic Acid
within chromosome.

6. Plasma membrane
● Thin, elastic , transparent ,semi permeable and regenerative
membrane.
● Composed of lipid bilayer with Protein molecules and
carbohydrates .
● Lipid molecules formed of cholesterol ,phosphoglycerides .

7. Mitochondria
● Power House of a cell
● Oxidation of food occurs
which results in release
of energy.
● Energy stored in ATP
form

8. Ribosome
● Protein Synthesis
● Tiny granules composed of RNA
● Present in outer surface of Nuclear
envelope,rough Endoplasmic Reticulum.

9. Endoplasmic Reticulum
● Series of
interconnecting
membrane canals
● Two Types - Smooth
Endoplasmic
Reticulum ,Rough
Endoplasmic
Reticulum

10. Golgi apparatus
● First observed by Camillo
Golgi.(1898)
● Consist of flat,disc shaped
sac.
● Stacked parallel to each other
● Convex cis or the forming
face and concave trans or the
maturing face.
● Important site of formation of
glycoprotein and glycolipids.

11. Lysosomes
● Suicidal Bags of the cell .
● Polymorphic
● Having hydrolytic enzyme.These enzyme
fiction at acidic pH .
● Help in carcinogenesis.

12. ● Membrane bound space in cytoplasm
● Bound by tonoplast
● In Plants tonoplast facilitates transport of ions and
other materials.
● In ameoba 'contractile vacuole’ important for
excretion .
● In protist ,food Vacuoles are formed by engulfing
the food particles.

13. Plastids
● Present only in plant cells
● Three types - chloroplast
(green), leucoplast (white)
chromoplast (of various
colours other than green)
● Chloroplast - ‘ kitchen of the
cell’

14. Plant cell and animal cell