science grade 7 questions

SCIENCE WORKSHEETS Topic # 1 RESPIRATION IN ORGNAISMS 1) How How brea breath thin ing g is dif difer eren entt rom rom res resi ira rati tion on! ! """"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" """"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" """"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" """"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" """"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" """"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" """"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" """"""""""""""""""""""""""""""""""""""""""""" #) $h% $h% doe does s an an athe athe&e &e br breath eath as aste terr and and dee deee err then 's'a& 's'a& ater ater (nishing (nishing the rae ! ************************* ************************* ************************* ************************* ************************* 1

************************* ************************* ************************* **************** ************************* ************************* ********************** +) Rearran earrange ge the o&&ow o&&owing ing arts arts o the reira eirator tor% % s%stem in order,  Trahea Trahea- Nose-A&.eo&i-/ro Nose-A&.eo&i-/ronhi-Nasa& nhi-Nasa& a.it%-/ronhio&e """"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" """"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" """""""""""""""""""""""""""""""""""""""""" 0) $hat $hat are are dif difer eren entt tt% %es es o Reir eirat atio ion! n! ************************** ***********" ************************** ***********" ************************** ***********" ) 2i 2ist st the the sim simi& i&ar arit itie ies s and and dif difer eren ene es s betw betwee een n aerobi and anaerobi reiration!

#

************************* ************************* ************************* **************** ************************* ************************* ********************** +) Rearran earrange ge the o&&ow o&&owing ing arts arts o the reira eirator tor% % s%stem in order,  Trahea Trahea- Nose-A&.eo&i-/ro Nose-A&.eo&i-/ronhi-Nasa& nhi-Nasa& a.it%-/ronhio&e """"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" """"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" """""""""""""""""""""""""""""""""""""""""" 0) $hat $hat are are dif difer eren entt tt% %es es o Reir eirat atio ion! n! ************************** ***********" ************************** ***********" ************************** ***********" ) 2i 2ist st the the sim simi& i&ar arit itie ies s and and dif difer eren ene es s betw betwee een n aerobi and anaerobi reiration!

#

************************* ************************* ************************* ************************* ************************* ************************* ************************* ************************* **************** 3) $h% $h% %ea %east st is 's 'sed ed in wine wine ma4i ma4ing ng in ind' d'st str% r%! ! ************************* ************************* ************************* ************************* ******** 5) $h% $h% d do o we we o oten ten s sne nee6 e6e e whe when n we we inh inha& a&e e a &ot &ot o d'st7&aden air! ************************* ************************* ************************* ************************* ************************* ************************* ************************* ************************* **************** +

8) $hen $hen doe does s a er erso son n need need art arti( i(a a&& re reis isra rati tion on! ! ************************* ************************* ************************* ************************* ******** 9) :rom wher where e an an the the er erso son n get get s' s'& &% % o o o;%gen or arti(a& reisration! ************************** ***********" ************************** ***********" 1&assi% the hanges in.o&.ed in the o&&owing roesses as h%sia& or hemia& hanges, a) Photos%nthesis 77777777777777777777777777777777 b) =isso&.ing s'gar in water 777777777777777777777777777 )/'rning o oa& 7777777777777777777777777777777 ##

d) Me&ting o wa; 7777777777777777777777777777 e) /eating a&'min'm to ma4e a&'min'm oi& 777777777777777777777777777777777 ) =igestion o ood 77777777777777777777777777777 3) $hen ba4ing soda is mi;ed with &emon F'ie b'bb&es are ormed with e.o&'tion o a gas" $hat t%e o hange is it! E;&ain" *********************** *********************** *********************** *********************** *********************** *********************** ******" *********************** *********************** **************" 5) $hen a and&e b'rns both h%sia& and hemia& hanges ta4e &ae" Identi% these hanges" Gi.e another e;am&e o a ami&iar roess in whih both hemia& and h%sia& hanges ta4e &ae" ************************* ************************* ************************* ************************* #+

************************* *******************" ************************* **********" ************************* "" ************************* ************************* ************************* ************************* ************************* *******************" *********" ************************* *********** 8) How wo'&d %o' show that setting o 'rd is a hemia& hange! ************************ ************************ ************************ ************************ ************************ ************************" ************************ ************************ ************************ #0

************************ ****" 9) E;&ain wh% b'rning o wood and 'tting it into sma&& iees are onsidered as two diferent t%es o hanges" ************************* **********" ************************* **********" ************************* **********" ************************* **********"****" ************************* ************************* ************************* ************************* ************************* ************************* ************************* *****************" ******************"" 1hange7/) " the o&&owing statements ertain to these hanges" >hoose the orret one" @i) Proess7 A is a hemia& hange @ii) Proess7 / is a hemia& hange @iii) /oth roesses A and / are hemia& hanges" @i.) None o these roesses is a hemia& hange" 10) Anaerobi bateria digest anima&s waste and rod'es biogas @>hange7A)" The biogas is then b'rnt as 'e& @>hange7/)" The o&&owing statements ertain to these hanges" >hoose the orret one" @i) Proess7 A is a hemia& hange @ii) Proess7/ is hemia& hange

#5

@iii) @i.)

/oth roesses A and / are hemia& hange None o these roesses is a hemia& hanges

1) State whether the o&&owing statements are tr'e or a&se" In ase a statements is a&se- write the orreted statements, a) >'tting a &og o wood into iees is a hemia& hange @Tr'e:a&se) E;&anation, *********************** *********************** *************" b) :ormation o man're rom &ea.es is a h%sia& hange" @Tr'e:a&se) E;&anation, *********************** *********************** ************** )Iron ies oated with 6in do not get r'sted easi&%"@Tr'e:a&se) E;&anation***************** *********************** *********************

#8

d) Iron and r'st are two diferent s'bstanes" @Tr'e:a&se) E;&anation***************** *********************** ********************"" e) >ondensation o steam is not a hemia& hange @Tr'e:a&se) E;&anation***************** *********************** ********************"" 13) :i&& in the b&an4s a) $hen arbon dio;ide is assed thro'gh &ime water- it t'rns mi&4% d'e to the ormation o ********************** b) The hemia& name o ba4ing soda is ***************** )Two methods b% whih r'sting o iron an be re.ented are *********"" Or ********** and"******"" $ith hromi'm or *******" d) >hanges in whih on&% ******* roerties o a s'bstane hange are a&&ed h%sia& hanges" e) >hanges in whih new s'bstanes are ormed are a&&ed ********* hanges #9

+<

Topic# 4

 WASTE WATER STORY 

1) $hat is sewage! E;&ain wh% it is harm'& to disharge 'ntreated sewage into ri.ers or seas" ************************ ************************ ************************ ************************ ************************ ************************ " ************************ ***********" ************************ ************************ ************************ ************************ ************************ ***********************" *****************"" #) $h% sho'&d oi&s and ats be not re&ased in the drain! E;&ain" ************************ ************************ +1

************************ ************************ ************************ ************************ " ************************ ** +) $hih da% is e&ebrated as $or&d $ater =a%! ************************ ********"" 0) $hat are diferent t%es o ontaminants or im'rities resent in sewage! ************************ *********"" ************************ ***********"" ************************ **********"" ************************ **********""********" ************************ **" ************************ **********""

+#

) =esribe the stes in.o&.ed is getting &ari(ed water rom waste water! ************************* ************************* ************************* ************************* ************************* *******************" ************************* **********" ************************* ************************* ************************* ************************* ************************* *******************" ************************* **********" ************************* ************************* ************************* ************************* ************************* *******************" ************************* **********" ++

3) $hat is s&'dge! E;&ain how it is treated" ************************* ************************* ************************* ************************* ************************* *******************" ************************* **********" ************************* ************************* ************************* ************************* ************************* *******************" ************************* **********" 5) ntreated h'man e;reta are hea&th ha6ard" E;&ain ************************ ************************ ************************ ************************ ************************ ************************ " +0

************************ ************************ ************"

8)

Name two hemia&s 'sed to disinet water" ************************ **********" ************************ **********"

9) E;&ain the 'ntion o bar sreens in a waste water treatment &ant" ************************* ************************* ************************* ************************* ******** 1