Lecture 1 - Cells - The Building Blocks of Life

BIOLOGY CHAPTER 1 Lecture prepared by: Waleed Zahoor  Tea Ro!h"# $tep%up Pa&#!ta"

CELL$: THE B'IL(I)G BLOC*$ O+ LI+E

LEAR)I)G OB,ECTI-E$: ● ● ● ●

Ide"t#.y the /ar#ou! copo"e"t! o. pla"t a"d a"#al cell! /#!#ble u"der a l#0ht #cro!cope Copare a"d co"tra!t the !tructure o. pla"t a"d a"#al cell! Apprec#ate the #porta"ce o. the cell !ur.ace ebra"e (#..ere"t#ate bet2ee" the ter! cell3 t#!!ue3 or0a" a"d or0a" !y!te

A cell #! a ba!#c u"#t o. l#.e It co"!#!t! o. a a!! o. l#/#"0 atter called protopla!

PROTOPLA$4: It #! a cople5 6elly%l#&e !ub!ta"ce #" 2h#ch !e/eral che#cal react#o"! ta&e place Water .or! 789 to 89 o. the total protopla!3 2herea! the re!t o. #t copr#!e! o. #"eral

!alt! a"d ba!#c or0a"#c copou"d! ;carbohydrate!3 prote#"! a"d .at!< The copo!#t#o" o. protopla! #! "ot the !ae .or all the cell! a! #t #! a #5ture Copo!#t#o" o. the protopla! o. u!cle cell! ay be d#..ere"t .ro the copo!#t#o" o. protopla! o. the cell! #" the lu"0!

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The protopla! o. a cell co"!#!t! o. = a#" part!:  )ucleu! Cytopla! Cell !ur.ace ebra"e

The d#a0ra belo2 !ho2! a typ#cal a"#al cell 2#th the a#"  part! o. a cell labeled alo"0 2#th other or0a"elle!

The d#a0ra belo2 !ho2! a typ#cal pla"t cell 2#th the a#"  part! o. a cell labeled alo"0 2#th other or0a"elle!

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 )ucleu!:

The "ucleu! #! a ebra"e bou"d !tructure that co"ta#"! the cell>! hered#tary #".orat#o" a"d co"trol! the cell>! 0ro2th a"d

reproduct#o" It #! coo"ly the o!t pro#"e"t or0a"elle #" the cell The "ucleu! #! !urrou"ded by a !tructure called the "uclear e"/elope Th#! ebra"e !eparate! the co"te"t! o. the "ucleu! .ro the cytopla! The cell>! chroo!oe! are al!o hou!ed 2#th#" the "ucleu! Chroo!oe! co"ta#" ()A 2h#ch pro/#de! the 0e"et#c #".orat#o" "ece!!ary .or the product#o" o. other cell copo"e"t! a"d .or the reproduct#o" o. l#.e There are al!o !oe !pher#cal !tructure! called "ucleol# Each "ucleolu! play! a part #" the bu#ld#"0 o. the prote#"!

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Cytopla!:

The part o. the protopla! !urrou"d#"0 the area arou"d the "ucleu! #! called cytopla! It .or! the lar0e!t part o. the cell a"d #! the place 2here o!t l#.e proce!!e! occur +ollo2#"0 are !oe o. the #porta"t or0a"elle! #" the cell 2h#ch are ebedded #" the cytopla!

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4#tocho"dr#a:

4#tocho"dr#a are !all !pher#cal or rod%!haped or0a"elle! The a#" .u"ct#o" o. the #tocho"dr#o" #! the  product#o" o. e"er0y3 #" the .or o. ade"o!#"e tr#pho!phate ;ATP< The cell u!e! th#! e"er0y to per.or the !pec#.#c 2or& "ece!!ary .or cell !ur/#/al a"d .u"ct#o" ●

Ce"tr#ole:

A ce"tr#ole #! a pa#r o. t#"y !tructure! clo!e to the "ucleu! They play a part #" cell d#/#!#o" a"d are ab!e"t #" o!t o. the pla"t cell! ●

-acuole:

A /acuole #! a ebra"e%bou"d !ac that play! role! #" #"tracellular d#0e!t#o" a"d the relea!e o. cellular 2a!te product! ● A"#al cell! ay ha/e a"y !all /acuole! 2h#ch are u!ually "ot pera"e"t -acuole! ay co"ta#" 2ater a"d .ood !ub!ta"ce! ● A pla"t cell ha! a lar0e ce"tral /acuole 2h#ch co"ta#"! a l#?u#d called cell !ap It co"ta#"! d#!!ol/ed !ub!ta"ce! !uch a! !u0ar3 #"eral !alt! a"d a#"o ac#d! Th#! lar0e /acuole #! e"clo!ed by a ebra"e called the to"opla!t

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Cell !ur.ace ebra"e:

The cell !ur.ace #! !urrou"ded e5ter"ally by a cell !ur.ace ebra"e3 al!o called the pla!a ebra"e It #! a part#ally pereable ebra"e 2h#ch allo2! o"ly certa#" !ub!ta"ce! to lea/e or e"ter the cell $##lar ebra"e! ay al!o !urrou"d lar0e !pace! or /acuole! 2#th#" the cell ●

Cell 2all:

I" a pla"t cell3 there #! a cell 2all 2h#ch e"clo!e! the 2hole cell The cell 2all #! ade o. cellulo!e It 0#/e! the cell !tructural !upport a"d #! copletely pereable It protect! the cell .ro #"6ury ●

Chloropla!t!:

Chloropla!t! are !pec#al#@ed or0a"elle! .ou"d #" all h#0her pla"t cell! The!e or0a"elle! co"ta#" the pla"t cell>! chlorophyll3 he"ce pro/#de the 0ree" color They a!!#!t the  pla"t #" the proce!! o. photo!y"the!#! ●

Pla!t#d!:

Pla!t#d! are a6or or0a"elle! .ou"d #" the cell! o. pla"t! a"d al0ae Pla!t#d! are the !#te o. a"u.acture a"d !tora0e o. #porta"t che#cal copou"d! u!ed by the cell Pla!t#d! o.te" co"ta#" p#0e"t! u!ed #" photo!y"the!#!3 a"d the type! o. p#0e"t!  pre!e"t ca" cha"0e or deter#"e the cell>! color 

(I++ERE)CE$ BETWEE) PLA)T A)( A)I4AL CELL$ Animal Cell

Plant Cell

Shape:

Round (irregular shape)

Rectangular (fixed shape)

Chloroplast:

Animal cells don't have chloroplasts

Plant cells have chloroplasts because they make their own food

Vacuole:

ne or more small vacuoles (much smaller than plant cells)!

ne" large central vacuole taking up #$% of cell volume!

Centrioles:

Present in all animal cells

nly present in lower plant forms!

Plastids:

Absent

Present

Cell wall:

Absent

Present

Plasma Membrane:

only cell membrane

cell wall and a cell membrane

$PECIALIZE( CELL$3 TI$$'E$3 ORGA)$ A)( ORGA) $Y$TE4$ (I++ERE)TIATIO): Th#! #! the proce!! #" 2h#ch a cell #! !pec#al#@ed .or a !pec#.#c .u"ct#o" +or e5aple3 hua" cell!  becoe d#..ere"t#ated to .or /ar#ou! type! 2h#ch #"clude l#/er cell!3 u!cle cell!3 !per cell! etc 2herea! pla"t cell! #" root! a"d !te! becoe d#..ere"t#ated to .or d#..ere"t type! o. cell! #"clud#"0 5yle cell! a"d phloe cell!

4O(I+ICATIO) O+ CELL $TR'CT'RE$ +OR $PECI+IC +')CTIO)$: ●

Root ha#r call:

Be#"0 lo"0 a"d "arro23 the root ha#r #"crea!e! the !ur.ace area to /olue rat#o o. the cell .or e..#c#e"t ab!orpt#o" o. 2ater a"d #"eral !alt! .ro the !o#l The th#" cell 2all al!o !peed! up the ab!orpt#o" proce!!

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Red blood cell:

Th#" ce"tral port#o"

The red blood cell co"ta#"! a red p#0e"t called heo0lob#" 2h#ch e"able! the cell ! to tra"!port o5y0e" .ro the lu"0! to all part! o. the body It! c#rcular3 b#co"ca/e !hape #"crea!e! !ur.ace area to /olue rat#o A! a re!ult3 o5y0e" ca" d#..u!e #"to a"d out o. the cell at a .a!ter rate

TI$$'E$3 ORGA)$ A)( $Y$TE4$ ●

TI$$'E:

A t#!!ue #! a 0roup o. cell! 2h#ch ha/e a coo" or#0#" a"d a !##lar !tructure3 2h#ch e"able! the to per.or a part#cular .u"ct#o" $oe e5aple! #"clude: co""ect#/e t#!!ue!3 u!cle t#!!ue! etc ●

ORGA)$:

A" or0a" #! a 0roup o. d#..ere"t t#!!ue! 2or&#"0 to0ether a"d e"abl#"0 the or0a" to per.or #t! .u"ct#o"! The !toach .or e5aple #! ade .ro 0la"dular t#!!ue!3 u!cular t#!!ue a"d co""ect#/e t#!!ue! alo"0 2#th "er/ou! t#!!ue Other e5aple! o. or0a"! #"clude bra#"3 #"te!t#"e! a"d the &#d"ey! $oe pla"t or0a"! #"clude lea.3 !te3 root etc ●

ORGA) $Y$TE4$:

$e/eral or0a"! 2or&#"0 to0ether .or a !pec#al purpo!e a&e up a" or0a" !y!te $oe e5aple!

o. or0a" !y!te! are: the re!p#ratory !y!te3 the d#0e!t#/e !y!te a"d the e"docr#"e !y!te