The Cell Class VIII

7/23/2019 The Cell Class VIII

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Presentation for Class VIIIPresented by: Miss. Farheen

The



Basic structural & functionalunit of all living organisms.

Also known as buildingblocks of the body.

The Cell



Robert Hook discovered the cell in1665.

He observed the slices of corkand bark of trees under a

microscoe and observe the

numbers of tiny comartmentsthat a aeared like a!Honeycomb". He gave the

term #ell to each of the bo$es.

Discovery

Story behind the

Discovery



• %heodor chwann & '. (.chleiden gave the cell theory.

• %he cell theory state that)

1. All the living organisms aremade u of cells.

*. +ew cells are formed from

the re)e$isting cells.,. #ells are considered as

building blocks of the body

Cell

Theory



#lassi-cation of rganisms on the basis of number of cells/nicellular

Classication ofOrganiss



1. #onsists of ingle #ell.

*. All the vital activities such as)Resiration0 Reroduction0igestion0 etc. are carried out

in a single cell. 2or 3$amle4Amoeba0 aramecium0 east0 etc.

!nicell"larOrganiss



1. #onsists of more than one cell.

*. i7erent organs erforms di7erent vitalactivities in the body. 2or e$amle4

Human being0 Animals0 lants0 3tc.

M"lticell"larOrganiss



i8e of cell ranging from a micron to few centimeters.

%he largest cell in lant) 9/:3 2 ##A.

:argest cell in animals) 3;; 2 A+ %R<#H.

mallest cell in animals) 'ycolasma

<n human beings)

:argest cell =+erve cells.

mallest cell =Blood cells.

Cell Si#e



#ells have di7erent shaes which varies from

organism to organism. ome shaes are) <rregular) Amoeba0 >.B.#.

Round or herical) 3gg0 R.B.#.

:ong & %hin) 'uscles cell.

3longated and Branched) +erve cells. Bean haed) ;uard cells of stomata.

:ong and Rectangular) 'esohyll cells inthe leaf.

Cell

Sha$es



tructure of a #ell

Str"ct"re of

Cell



o %hin outer covering of the cell.

o resent in both lants and animals.

o

also known as lasma 'embrane.o <n lants in additional covering is

resent around the cell membranecalled the cell wall.

o #ell wall rovides rigidity0 shae androtection to the cells.

Cell

Mebrane



o <t was discovered by Robert Brown.

o <t is sherical in shae resent in

the center of the cell.o <t acts as a control centre of all the

activities going on in the cell that?swhy it is considered as the %&'I(

of the cell.

("cle"s



Co$onents of ("cle"s

Co$onents of("cle"s



#lassi-cation of nucleus on the basis of comosition of nucleus.

Classication of

("cle"s



%hese cells having the rimitive

tye of nucleus. <t means thatthe nuclear material is notsurrounded by the nuclearmembrane. 2or e$amle4

Bacteria0 blue)green algae.

Pro)aryotic

Cells



%hese cells having true nucleus. <t

means nuclear material issurrounded by the nuclearmembrane. 2or e$amle4 All

lants & animals.

*")aryotic

Cells



Pro)aryotic Cells *")aryotic CellsPriitive ty$e ofn"cle"s is $resent.

Tr"e n"cle"s is$resent.

("clear aterial is nots"rro"nded by n"clear

ebrane.

("clear aterial iss"rro"nded by n"clear

ebrane.

D.(.'. circ"lar inCyto$las.

D.(.'. is long andlinear in str"ct"re.

+istone $rotein isabsent.

+istone $rotein is$resent.

,-S ty$e of /-S ty$e of

Di0erence bet1eenPro)aryotic 2

*")aryotic Cells



o %his is @elly like substance.

o All the chemical reactions and functions takeslace in #ytolasm.

o <t consist of some tiny structure called organelles.

o

i7erent organelles resent in the cytolasm are) 'itochondrion

3ndolasmic Reticulum

Ribosome?s

;olgi bodies

:ysosomes

lastids

vacuoles

Cyto$las



o <t is small sherical long rods or

-lamentous structure.o <t is called as Po1er +o"se of

the cell because it forms energy

in the form A%.

Mitochondrio

n



o <t coated mass of membrane.

o 2ound in lasma membrane.

o %here are two tyes of 3ndolasmic reticulum)o mooth 3ndolasmic reticulum without ribosome.

o Rough 3ndolasmic reticulum with ribosome.

o <t acts as cytoskeleton.

o <t rovides mechanical suort to the cell.

o

<t hels in rotein synthesis.

*ndo$lasic&etic"l"



o alade0 in 1C55 reorted Ribosome for the -rst time.

o

2ound in 'itochondrion0 chlorolast and nucleus.o %hese are sherical structure without membrane.

o %here are two tyes of ribosome?s resent in cells.o DE tye.

o FE tye.

o <t hels in rotein synthesis.

&ibosoe



o %his was discovered by #amillo ;olgi in

1FCF.

o <n lants it is known as ictyosome.o <t hels secretion and storage of many

roducts.

o <t acts like ackaging deartment.

o <t ready to deliver rotein roducts in thecell.

3olgi %odies



o <t was discovered by #hristian e uve in.

o %hese are small vacuoles in cytolasmwhich are -lled with digestive en8ymes.

o :ysosomes are resent animal cells only.

o <t is also known suicidal bags.

4ysosoes



o <t was discovered by >aldeyer.

o %hese are thread like structureresent in the nucleus.

o <t hels in transmitting charactersfrom one generation to the other.

o +umber of chromosomes in humanbeings is G6.

Chroosoes

l id



o %hese are found in lant cells only.

o <t hels in synthesis of food and storage

of carbohydrates0 liids and roteins.o lastids are of three tyes)

o :eucolast #olorless

o #hromolast ellow0 range and Red incolor

o #hlorolast ;reen in color.

Plastids

l



o <t is membrane bound cell organelles.

o Having no internal structure.o %hey are generally used to store cell

roducts or rotect the rest of the cell frominvading microorganisms.

o 9acuole are generally resent in lant cells.

Vac"oles

Di0 b t



'nial Cell Plant Cell#ell membrane is

resent.#ell membrane is

resent.

#ell wall is absent. #ell wall is resent.

lastid are absent. lastid are resent.

9acuoles are absent. 9acuoles are resent.

Di0erence bet1een'nial Cells and

Plant Cells



2acts about the cell.o 1*,G56DFCE

Documents

The Cell Class VIII