8/11/2019 Chapter 1&2 (form 4)

1/17

Chapter 1 Introduction to Biology

What is Biology ~The study of life and living organisms

Bios = life Logos = knowledge

Common characteristics of all living organisms

Growth

Movement

Nutrition (feeding)

Respiration

!"retion

Reprodu"tion

#ensitivity of responsiveness (respond to stimuli)

$o"omotion

Meta%olism

The study

of lifeScientific method

Differentfields of

study

Scientific skills and

manipulative skills

Scientificinvestigation

Observation

QuestionHypothesis

Experiment

Resultsnterpretation

!onclusion

!areersrelated to

"iology

Scientific attitudes and

noble values

"O#O$%

8/11/2019 Chapter 1&2 (form 4)

2/17

Importance of Biology

#tudy of environment & understand ' preserve e"osystems (identifying various

organisms ' their rea"tions to "hanges in their environment)

Manage natural resour"es

dvan"e in %iote"hnology geneti" engineering ' medi"ine (%etter prevention ' "ure of

diseases improve agri"ultural methods for %etter *uality produ"ts ' in"rease foodprodu"tion)

+now more a%out our %odies work ' how other organisms fun"tion

Field of study in Biology

gri"ulture

natomy (stru"ture ' organi,ation of organisms)

Biote"hnology (appli"ation of %iologi"al s"ien"e to manufa"turing industry)

Bio"hemistry (study of elements "ompounds ' "hemi"al rea"tion)

Botany (study of plants)

-ytology (s"ienti." study of "ells)

"ology (relationship %etween living organisms ' their environment)

m%ryology (development of em%ryo)

Geneti"s (how "hara"teristi"s are passed from parents to o/spring)

0istology (mi"ros"opi" study of tissues)

1"hthyology (study of .shes)

Marine %iology (o"ean plants ' animals ' their e"ologi"al relationship)

Medi"ine

Mi"ro%iology (study of mi"roorganisms)

Mole"ular %iology (%iology of "ell at the mole"ular level)

Morphology (study of the form 2 shape of an organism)

My"ology (study of fungi) Neuro%iology (nervous system)

3alaeontology (study of the forms of life e!isting in prehistori" times 4 fossils)

3arasitology (study of parasites)

3athology (nature of disease 4 "auses pro"ess ' development)

3hysiology (fun"tions ' life pro"esses of organisms)

#ystemati"s 2 Ta!onomy ("lassi."ation of life into phylum family genus spe"ies 5)

6eterinary medi"ine (medi"al diagnosti" ' therapeuti" prin"iples to wildlife)

6irology (study of viruses)

7oology (study of animals)

Careers

gri"ulturalist a*ua"ulturalist %io"hemist %iote"hnologist %otanist dentistry

dietitian e"ologist ethologist forester geneti"ist horti"ulturist mi"ro%iologist

my"ologists neuro%iologist optometrist pediatri"ian physiotherapist pharma"y

radiology surgeon to!i"ologist veterinarian ,oologist

8/11/2019 Chapter 1&2 (form 4)

3/17

Ways of studying Biology

Many s"ienti." skills are needed when you plan ' "arry out an e!periment8

#"ienti." skills "an %e divided into 29

a) s"ien"e pro"ess skills

%) manipulative skills

a) science process skills

3ro"ess skills :es"ription

;8 senses to gather information?8 -lassifying Group o%@e"ts %ased on their similarities 2 di/eren"es

A8 Measuring ' usingnum%ers

Make *uantitative o%servations using no8 ' tools withstandardi,ed units

8 1nferring se prior e!perien"es to draw "on"lusions ' e!plain events>8 3redi"ting #tate the out"ome of a future event %ased on prior

knowledgeC8 -ommuni"ating se words2graphi" sym%ols to des"ri%e an a"tion

o%@e"t2eventsD8 sing spa"eEtimerelationship

:es"ri%e "hanges in parameters with time

F8 1nterpreting data !plain an event2out"ome logi"ally using "olle"ted data8 :e.ning operationally 3rodu"e de.nition of a thing2event in terms that give it a

physi"al des"ription;H8 -ontrolling varia%les 1dentify whi"h varia%les have to %e kept "onstant ' whi"h

varia%les have to %e "hanged in an investigation;;8 0ypothesising Make a general statement a%out the relationship %etween a

manipulated varia%le ' a responding varia%le to e!plain anevent2o%servation

;?8 !perimenting 3lan ' "ondu"t a"tivities to test a "ertain hypothesis

b) manipulative skills can be learned during laboratory e!ercises)

" learn how to handle ' use apparatus materials ' spe"imen "orre"tly

"involve making proper drawings "leaning ' storing apparatus ' materials "orre"tly

#cienti$c method

;8 Make an o%servation

?8 #tate the pro%lem

A8 Iorm of hypothesis

8 1dentify the varia%les

a) manipulated varia%le (independent) & varia%le that is deli%erately "hanged

Scientific skills

Science rocess skills &ani ulative skills

8/11/2019 Chapter 1&2 (form 4)

4/17

%) responding varia%le (dependent) & depends on the manipulated varia%le

") .!ed varia%les & varia%les that are kept un"hanged or "ontrolled

>8 -ondu"t the e!periment (to the hypothesis)

C8 Re"ord the results

D8 naly,e the results

F8 1nterpret the data

8 :raw "on"lusion

;H83repare the report

%oble values

;8 1nterest ' "uriosity

?8 #ystemati" ' a""urate

A8 $ove ' respe"t the environment

8 Responsi%le for the safety of oneself ' others

>8 :iligent ' persevering

C8 Respe"tful wellEmannered ' "ooperative

D8

8/11/2019 Chapter 1&2 (form 4)

5/17

:rawing magni."ation = $inear dimension of the drawing $inear dimension of the o%@e"t

Chapter 2 & Cell #tructure ' Cell (rganisation

) What is cell *

re the %uilding %lo"ks for organisms8

1s the %asi" unit of stru"ture ' fun"tion in an organism8

Generally a "ell has A %asi" stru"tural features 9 plasma membrane+ nucleus+cytoplasm

,lasma membrane ~ a"t as a %arrier %etween the inside ' outside of the "ell8 1t "ontrols

the e!"hange of su%stan"es %etween the "ell ' its environment8

%ucleus4 ea"h "ell has a nu"leus8 1t "ontains the geneti" material of the "ell8

Cytoplasm4 a @ellyElike medium8 Many %io"hemi"al rea"tions take pla"e8

-ight microscope compound microscope)

sed to o%serve mi"ros"opi" "ells8 1t fo"uses ' magni.es an o%@e"t using ? lenses 9 an eyepiece' an ob.ective lens

light mi"rograph is a photograph taken through a light mi"ros"ope8

Give a ma! magni."ation of ;>HH times8

Mi"ros"ope magni."ation = eyepie"e magni."ation K o%@e"tive magni."ation

/lectron microscope

sed to reveal the detailed "ell stru"ture of a "ell8

n ele"tron mi"rograph is a photograph taken through an ele"tron mi"ros"ope8

3rodu"e a magni."ation of a%out >HH HHH times8

8/11/2019 Chapter 1&2 (form 4)

6/17

Functions of Cellular Components in ,lant ' nimal Cells

;8 3lasma mem%rane (nimal ' 3lant)

thin Je!i%le mem%rane

#urrounds the "ytoplasm of "ells

-onsists of phospholipid %ilayer protein ' "holesterol mole"ules

s a %oundary %etween the "ell ' its environment

s a sele"tive %arrier 9 "ontrol the passage of materials in ' out of the "ells

Regulates e!"hange of nutrients respiratory gases ' waste produ"ts %etween "ell ' its

environment 0elp to re"ogni,e other "ells

8g 9 1t allow

8/11/2019 Chapter 1&2 (form 4)

7/17

$argest organelle in the "ell

#pheri"al 2 oval in shaped

#urrounded %y a dou%leElayered nu"lear mem%rane

-ontains 4 "hromosomes nu"leoplasm ' nu"leolus

-hromosomes 9 "ontains deo!yri%onu"lei" a"id (:N) the mole"ule of inheritan"e

-hromatin 9 a network of long threadElike stru"tures

Nu"leolus 9 involves in the synthesis of ri%osome ' RN

Nu"leoplasm 9 "ontains en,ymes ne"essary for the repli"ation of :N ' the synthesis ofRN

Nu"lear mem%rane 9 regulates e!"hange %etween nu"leus ' "ytoplasm

"ts as a "ontrol "entre for the a"tivities of a "ell

3rodu"es ri%osomes ' ri%onu"lei" a"id (RN)

3lays an essential role in "ell division

-ell without nu"leus have a short life span (e8g red %lood "ells of humans)

>8 Ri%osome (nimal ' 3lant) NonEmem%rane %ound parti"les

#mall dense spheri"al granules

a"h ri%osome is made up of RN ' proteins

tta"h to the outer surfa"e of R forming rough R

#ite of protein synthesis

#ome o""ur freely suspended in the "ytoplasm

-ells that are a"tive in protein synthesis have numerous ri%osomes

C8 R E ndoplasmi" Reti"ulum (nimal ' 3lant) -onsists of rough R ' smooth R

Rough R

E -onsists of ri%osomes on its outer surfa"eE -onsists of inter"onne"ted system of Jattened sa"sE The mem%rane of rough R is "ontinuous with an outer layer of nu"lear

mem%raneE Transport proteins synthesi,ed %y the ri%osomes through the cisternae

#mooth R

E has no ri%osomesE "onsists of an inter"onne"ted tu%ular systemE side of lipid ' steroid synthesisE deto!i."ation of drugs ' to!ins

R divides the "ytoplasm into "ompartments ' in"reases the surfa"e area for %io"hemi"al

rea"tions

D8 Golgi apparatus (nimal ' 3lant)

-onsists of a sta"k of Jattened sa"s %ounded %y mem%rane -olle"ts pa"ks ' distri%utes mole"ules synthesi,ed in the "ell

3rodu"es gly"oproteins polysa""harides ' se"retory en,ymes

Iorm lysosomes

Transports ' stores lipids

F8 $ysosomes (nimal) #mall spheri"al sa"s "overed %y a single mem%rane

Iormed %y pit"hing o/ from the Golgi apparatus

-ontain digestive en,ymes

8/11/2019 Chapter 1&2 (form 4)

8/17

Break down unwanted mole"ules 2 wornEout organelles

1nvolve in autolysis ' digesting of foreign parti"les

Iuse with food va"uoles to digest materials whi"h the "ell "onsumes

-ompletely %reaks down the "ell after its death

Release en,ymes outside the "ell to digest e!ternal material

%undant in phago"yti" "ells eg whit %lood "ells

8 Mito"hondrion (nimal ' 3lant) #pheri"al or rod shaped

-onsists of ? mem%ranes (inner mem%rane is folded to form "ristae)

-ontains a matri! with a few ri%osomes a "ir"ular :N mole"ule ' phosphate granules

#ite of aero%i" "ellular respiration

3rodu"es T3 (adenosine triphosphate)

+nown as the powerhouse of the "ell

;H8 -hloroplast (3lant) :is" shaped

? mem%ranes (inner ' outer mem%rane)

Iound in palisade "ells spongy mesophyll "ells ' guard "ells #ite of photosynthesis

-ontain the green pigment "alled chlorophyll

-hlorophyll gives the leaves its green "olour

-hlorophyll a%sor%s light energy from the sun for photosynthesis

;;8 -entrioles (nimal)

8/11/2019 Chapter 1&2 (form 4)

9/17

shape2regular in shape %sent Cell all -ellulose "ell wall present

sually small '

numerous .lled withwater 2 food

6acuole 0as one or a few large

va"uoles .lled with "ellsap

%sent Chloroplast 3resent

3resent throughout the"ell Cytoplasm

Normally "on.ned to a thin

layer at the edge of the"ell

sually "entralised -ocation of nucleus sually at the edge of the

"ell

3resent Centriole %sent

8/11/2019 Chapter 1&2 (form 4)

10/17

ni"ellalar organisms are mi"ros"opi" ' are also known as mi"roorganisms8

Multi"ellar organisms are made up of more than one "ell8 They are usually larger in si,e '

are more "omple! than uni"ellular organisms8

ll uni"ellular ' multi"ellular organisms "an "arry out the following life pro"ess9

a) feeding (nutrition)

%) respiration (%reathing)

") e!"retion

d) lo"omotion (moving)

e) sensitivity (responding to stimuli)

f) reprodu"tion

g) growth

-iving ,rocess of 9nicellular (rganisms

Amoeba proteus

is a uni"ellular organisms

"an rea"h a ma! length of H8?>mm

@ust visi%le to the naked eye as a tiny white spe"k

most are free living ' found in fresh water marine environment ' in soil water

irregular in shape

"onsists of a single "ell surrounded %y a plasma mem%rane

has an oval nu"leus surrounded %y "ytoplasm8 1ts "ytoplasm "onsists of an outer thin

"lear e"toplasm ' an inner granular endoplasm

uses pseudopodiafor feeding ' movement

Ieeding 9

E Amoebahas no "hlorophyll ("annot "arry out photosynthesis)

E -arry out holo,oi" nutrition (ingestion digestion a%sorption assimilation '

egestion)

E feeds on %a" ' algae

E when theAmoeba "omes in "onta"t with food it puts its pseudopodiaall round

the food to en"lose it in a drop of ater forming a food vacuole ingestion)

E lysosome fuses with the food va"uole8 The food parti"le is digested %y the

en,ymes released %y lysosome digestion)

E the digested su%stan"es are absorbedinto the "ytoplasm ' assimilated

8/11/2019 Chapter 1&2 (form 4)

11/17

E theAmoeba moves away leaving undigested food in the water egestion)

E ingestion ' egestion "an o""ur at any point on the "ell surfa"e

$o"omotion 9

E Amoeba moves %y putting out new pseudopodia in front ' withdrawing others

%ehind

E Movement %y means of pseudopodia is known as amoe%oid movement

E The shape of theAmoeba"hanges as it moves

Reprodu"tion 9

E reprodu"e %y %inary division (one "ell divides into two "ells)

E ase!ual reprodu"tion whi"h does not involve the fusion of gametes

E when food is a%undantAmoeba reprodu"es %y binary $ssion8 When the

Amoeba rea"hes a ma! si,e the nu"leus divides into ? ' the "ytoplasm

"onstri"ts forming ? newAmoeba

E Amoeba does not reprodu"e se!ually

Respiration

E e!"hange of

8/11/2019 Chapter 1&2 (form 4)

12/17

E moves towards favoura%le stimuli ("hemi"al se"reted %y food parti"les)

Growth

E grows %y synthesising new "ytoplasm

Cell #pecialisation in :ulticellular (rganisms

Mi"roorganisms "onsist of more than one "ell8 (eg9%ryophytes ferns "onifers angiosperms

' animals)

re more "omple! than uni"ellular organisms8

Within a multi"ellular organism there are di/erent types of "ells8 a"h type of "ell

spe"ialises in performing a parti"ular fun"tions (division of la%our)

g 9 red %lood "ell (in animal transports

8/11/2019 Chapter 1&2 (form 4)

13/17

;8 -ell

nimal "ell

o mus"le "ell & a%le to "ontra"t ' rela! ' are involved in a movement (peristalsis walking '

%reathing)

o red %lood "ell & transport

8/11/2019 Chapter 1&2 (form 4)

14/17

o neurons are spe"iali,ed to transmit nerve

impulseso transmits ' "oordinates message around the

%ody

3lant Tissues

8issue #tructure ' Function

pidermis o outermost layer of "ells "overing a plant

o protects the underlying tissues form

physical damage ' infectiono reduces ater loss

o some are modi.ed to form guard "ells for

gaseous e!"hange through stomatal poreo some are modi.ed to %e"ome root hairs

Ground tissue o mainly paren"hyma "ells

o are the tissues that pa"k the spa"es %etween the

epidermis ' the vas"ular tissueo provides support ' strengthens the plant

young stems ' leaves)o store food

Meristemi" tissue o found at the shoot ape! root ape! ' the lateral

meristems ("am%ium)o "onsists of "ells that divide a"tively (mitosis)

o produ"es new "ells %y "ell division

3hotosyntheti" tissue o palisade mesophyll "ells

o makes food %y photosynthesis

6as"ular tissue Kylem ' phloem

o !ylem transports 0?< ' dissolved mineral saltsfrom the roots to the shoot

o phloem transport organi" produ"ts of

photosynthesis from the leaves to other parts ofthe plant

A8

8/11/2019 Chapter 1&2 (form 4)

15/17

system 3rote"ts against me"hani"al in@ury

infe"tion ' dehydration of the %ody") #keletal system 3rovides %odily support (lo"omotion '

movement) 3rote"tion of internal organs

tta"hment sites for mus"les

Bones "artilagetendons ligaments

d) Respiratory

system

Gaseous e!"hange

:elivers

8/11/2019 Chapter 1&2 (form 4)

16/17

The Juid inside the "ell is "alled the intracellular 7uid8

nything outside the "ell is said to %e e!tracellular8

? types of e!tra"ellular Juids in animals9

a) e!tra"ellular Juid that surrounds ' %athes the "ells

%) the plasma whi"h is the li*uid "omponent of the %lood

To stay alive the "ells in a multi"ellular organism must remain %athed in a 7uid (o/er

nutrients ' "arries away meta%oli" wastes)8

The e!tracellular 7uid tissue 7uid)is known as the internal environment (within the

organism)8

1n order to survive a multi"ellular organisms has to keep its internal environment within

tolera%le limits8

1n "omple! multi"ellular organisms only the surfa"e "ells that are in "onta"t with the

e!ternal environment are a%le to e!"hange su%stan"es with it8

;omeostasis

E 1s the self"regulationof the internal environment of a living organism8

E Ia"tors a/e"ting the internal environment (that must %e keep "onstant are)9

a) %ody temperature

%) %lood glu"ose level

") %lood p0

d' O P of

8/11/2019 Chapter 1&2 (form 4)

17/17

E -ells tissues organs ' organ systems work together to maintain the internal environment

within a range that the %ody "ells "an tolerate8

E ? organ systems responsi%le for control ' coordinationin multi"ellular organisms 9

a) nervous system

%) endo"rine system

Features #ystems that control

Body temperature Nervous ' endo"rineBlood glu"ose level endo"rineBlood p0 Nervous ' endo"rineO P of