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BIOLOGY 0610/04Paper 4 Theory (Extended) For examination from 2023MARK SCHEME

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Specimen

0610

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Gen

eric

Mar

king

Prin

cipl

es

Thes

e ge

nera

l mar

king

prin

cipl

es m

ust b

e ap

plie

d by

all

exam

iner

s w

hen

mar

king

can

dida

te a

nsw

ers.

The

y sh

ould

be

appl

ied

alon

gsid

e th

e sp

ecifi

c co

nten

t of t

he m

ark

sche

me

or g

ener

ic le

vel d

escr

ipto

rs fo

r a q

uest

ion.

Eac

h qu

estio

n pa

per a

nd m

ark

sche

me

will

als

o co

mpl

y w

ith th

ese

mar

king

pr

inci

ples

.

GE

NE

RIC

MA

RK

ING

PR

INC

IPLE

1:

Mar

ks m

ust b

e aw

arde

d in

line

with

:

•th

e sp

ecifi

c co

nten

t of t

he m

ark

sche

me

or th

e ge

neric

leve

l des

crip

tors

for t

he q

uest

ion

•th

e sp

ecifi

c sk

ills

defin

ed in

the

mar

k sc

hem

e or

in th

e ge

neric

leve

l des

crip

tors

for t

he q

uest

ion

•th

e st

anda

rd o

f res

pons

e re

quire

d by

a c

andi

date

as

exem

plifi

ed b

y th

e st

anda

rdis

atio

n sc

ripts

.

GE

NE

RIC

MA

RK

ING

PR

INC

IPLE

2:

Mar

ks a

war

ded

are

alw

ays

who

le m

arks

(not

hal

f mar

ks, o

r oth

er fr

actio

ns).

GE

NE

RIC

MA

RK

ING

PR

INC

IPLE

3:

Mar

ks m

ust b

e aw

arde

d po

sitiv

ely:

•m

arks

are

aw

arde

d fo

r cor

rect

/val

id a

nsw

ers,

as

defin

ed in

the

mar

k sc

hem

e. H

owev

er, c

redi

t is

give

n fo

r val

id a

nsw

ers

whi

ch g

o be

yond

the

scop

e of

the

sylla

bus

and

mar

k sc

hem

e, re

ferr

ing

to y

our T

eam

Lea

der a

s ap

prop

riate

•m

arks

are

aw

arde

d w

hen

cand

idat

es c

lear

ly d

emon

stra

te w

hat t

hey

know

and

can

do

•m

arks

are

not

ded

ucte

d fo

r err

ors

•m

arks

are

not

ded

ucte

d fo

r om

issi

ons

•an

swer

s sh

ould

onl

y be

judg

ed o

n th

e qu

ality

of s

pelli

ng, p

unct

uatio

n an

d gr

amm

ar w

hen

thes

e fe

atur

es a

re s

peci

fical

ly a

sses

sed

by th

e qu

estio

n as

indi

cate

d by

the

mar

k sc

hem

e. T

he m

eani

ng, h

owev

er, s

houl

d be

una

mbi

guou

s.

GE

NE

RIC

MA

RK

ING

PR

INC

IPLE

4:

Rul

es m

ust b

e ap

plie

d co

nsis

tent

ly, e

.g. i

n si

tuat

ions

whe

re c

andi

date

s ha

ve n

ot fo

llow

ed in

stru

ctio

ns o

r in

the

appl

icat

ion

of g

ener

ic le

vel

desc

ripto

rs.

GE

NE

RIC

MA

RK

ING

PR

INC

IPLE

5:

Mar

ks s

houl

d be

aw

arde

d us

ing

the

full

rang

e of

mar

ks d

efin

ed in

the

mar

k sc

hem

e fo

r the

que

stio

n (h

owev

er; t

he u

se o

f the

full

mar

k ra

nge

may

be

lim

ited

acco

rdin

g to

the

qual

ity o

f the

can

dida

te re

spon

ses

seen

).

0610

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GE

NE

RIC

MA

RK

ING

PR

INC

IPLE

6:

Mar

ks a

war

ded

are

base

d so

lely

on

the

requ

irem

ents

as

defin

ed in

the

mar

k sc

hem

e. M

arks

sho

uld

not b

e aw

arde

d w

ith g

rade

thre

shol

ds o

r gra

de

desc

ripto

rs in

min

d.

Scie

nce-

Spec

ific

Mar

king

Prin

cipl

es

1 E

xam

iner

s sh

ould

con

side

r the

con

text

and

sci

entif

ic u

se o

f any

key

wor

ds w

hen

awar

ding

mar

ks. A

lthou

gh k

eyw

ords

may

be

pres

ent,

mar

ks

shou

ld n

ot b

e aw

arde

d if

the

keyw

ords

are

use

d in

corr

ectly

.

2 Th

e ex

amin

er s

houl

d no

t cho

ose

betw

een

cont

radi

ctor

y st

atem

ents

giv

en in

the

sam

e qu

estio

n pa

rt, a

nd c

redi

t sho

uld

not b

e aw

arde

d fo

r any

co

rrec

t sta

tem

ent t

hat i

s co

ntra

dict

ed w

ithin

the

sam

e qu

estio

n pa

rt. W

rong

sci

ence

that

is ir

rele

vant

to th

e qu

estio

n sh

ould

be

igno

red.

3 A

lthou

gh s

pelli

ngs

do n

ot h

ave

to b

e co

rrec

t, sp

ellin

gs o

f syl

labu

s te

rms

mus

t allo

w fo

r cle

ar a

nd u

nam

bigu

ous

sepa

ratio

n fro

m o

ther

syl

labu

s te

rms

with

whi

ch th

ey m

ay b

e co

nfus

ed (e

.g. e

than

e / e

then

e, g

luca

gon 

/ gly

coge

n, re

fract

ion 

/ ref

lect

ion)

.

4 Th

e er

ror c

arrie

d fo

rwar

d (e

cf) p

rinci

ple

shou

ld b

e ap

plie

d, w

here

app

ropr

iate

. If a

n in

corr

ect a

nsw

er is

sub

sequ

ently

use

d in

a s

cien

tific

ally

co

rrec

t way

, the

can

dida

te s

houl

d be

aw

arde

d th

ese

subs

eque

nt m

arki

ng p

oint

s. F

urth

er g

uida

nce

will

be

incl

uded

in th

e m

ark

sche

me

whe

re

nece

ssar

y an

d an

y ex

cept

ions

to th

is g

ener

al p

rinci

ple

will

be

note

d.

5 ‘L

ist r

ule’

gui

danc

e

Fo

r que

stio

ns th

at re

quire

n re

spon

ses

(e.g

. Sta

te tw

o re

ason

s …

):

•Th

e re

spon

se s

houl

d be

read

as

cont

inuo

us p

rose

, eve

n w

hen

num

bere

d an

swer

spa

ces

are

prov

ided

. •

Any

resp

onse

mar

ked

igno

re in

the

mar

k sc

hem

e sh

ould

not

cou

nt to

war

ds n

. •

Inco

rrec

t res

pons

es s

houl

d no

t be

awar

ded

cred

it bu

t will

stil

l cou

nt to

war

ds n

. •

Rea

d th

e en

tire

resp

onse

to c

heck

for a

ny re

spon

ses

that

con

tradi

ct th

ose

that

wou

ld o

ther

wis

e be

cre

dite

d. C

redi

t sho

uld

not b

e aw

arde

d fo

r any

resp

onse

s th

at a

re c

ontra

dict

ed w

ithin

the

rest

of t

he re

spon

se. W

here

two

resp

onse

s co

ntra

dict

one

ano

ther

, thi

s sh

ould

be

trea

ted

as a

sin

gle

inco

rrec

t res

pons

e. •

Non

-con

tradi

ctor

y re

spon

ses

afte

r the

firs

t n re

spon

ses

may

be

igno

red

even

if th

ey in

clud

e in

corr

ect s

cien

ce.

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6 C

alcu

latio

n sp

ecifi

c gu

idan

ce

C

orre

ct a

nsw

ers

to c

alcu

latio

ns s

houl

d be

giv

en fu

ll cr

edit

even

if th

ere

is n

o w

orki

ng o

r inc

orre

ct w

orki

ng, u

nles

s th

e qu

estio

n st

ates

‘sho

w

your

wor

king

’.

Fo

r que

stio

ns in

whi

ch th

e nu

mbe

r of s

igni

fican

t fig

ures

requ

ired

is n

ot s

tate

d, c

redi

t sho

uld

be a

war

ded

for c

orre

ct a

nsw

ers

whe

n ro

unde

d by

th

e ex

amin

er to

the

num

ber o

f sig

nific

ant f

igur

es g

iven

in th

e m

ark

sche

me.

Thi

s m

ay n

ot a

pply

to m

easu

red

valu

es.

Fo

r ans

wer

s gi

ven

in s

tand

ard

form

(e.g

. a ×

10n ) i

n w

hich

the

conv

entio

n of

rest

rictin

g th

e va

lue

of th

e co

effic

ient

(a) t

o a

valu

e be

twee

n 1

and

10 is

not

follo

wed

, cre

dit m

ay s

till b

e aw

arde

d if

the

answ

er c

an b

e co

nver

ted

to th

e an

swer

giv

en in

the

mar

k sc

hem

e.

U

nles

s a

sepa

rate

mar

k is

giv

en fo

r a u

nit,

a m

issi

ng o

r inc

orre

ct u

nit w

ill n

orm

ally

mea

n th

at th

e fin

al c

alcu

latio

n m

ark

is n

ot a

war

ded.

E

xcep

tions

to th

is g

ener

al p

rinci

ple

will

be

note

d in

the

mar

k sc

hem

e.

7 G

uida

nce

for c

hem

ical

equ

atio

ns

M

ultip

les 

/ fra

ctio

ns o

f coe

ffici

ents

use

d in

che

mic

al e

quat

ions

are

acc

epta

ble

unle

ss s

tate

d ot

herw

ise

in th

e m

ark

sche

me.

S

tate

sym

bols

giv

en in

an

equa

tion

shou

ld b

e ig

nore

d un

less

ask

ed fo

r in

the

ques

tion

or s

tate

d ot

herw

ise

in th

e m

ark

sche

me.

Mar

k sc

hem

es w

ill u

se th

ese

abbr

evia

tions

:

; se

para

tes

mak

ing

poin

ts/

alte

rnat

ives

()

th

e w

ord 

/ phr

ase

in b

rack

ets

is n

ot re

quire

d bu

t set

s th

e co

ntex

tA

acce

pt (f

or a

nsw

ers

corr

ectly

cue

d by

the

ques

tion,

or g

uida

nce

for e

xam

iner

s)an

d bo

th re

spon

ses

requ

ired

for t

he m

ark

any

[num

ber]

from

: ac

cept

the

[num

ber]

of v

alid

resp

onse

sAV

P al

tern

ativ

e va

lid p

oint

AW

alte

rnat

ive

wor

ding

(whe

re re

spon

ses

vary

mor

e th

an u

sual

)ec

f er

ror c

arrie

d fo

rwar

dI

igno

re a

s irr

elev

ant

MP

mar

k po

int

note

: ad

ditio

nal m

arki

ng g

uida

nce

ora

or re

vers

e ar

gum

ent

R

reje

ctun

derli

ne

actu

al w

ord

give

n m

ust b

e us

ed b

y ca

ndid

ate

(gra

mm

atic

al v

aria

nts

acce

pted

)

0610

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chem

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r exa

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atio

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SPEC

IMEN

fro

m 2

023

Pag

e 5

of 1

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0

Que

stio

nA

nsw

erM

arks

Gui

danc

e

1(a)

(i)ab

sorp

tion

of (d

iges

ted)

nut

rient

s in

to th

e bl

ood

;1

1(a)

(ii)

any

thre

e fro

m:

lact

eal /

 lym

ph v

esse

l / ly

mph

atic

ves

sel ;

capi

llarie

s / b

lood

ves

sel ;

epith

eliu

m ;

mic

rovi

lli ;

larg

e su

rface

are

a ;

AVP

; e.g

. epi

thel

ium

con

tain

s go

blet

cel

ls

3

1(b)

(i)(b

lood

) pla

sma

;1

1(b)

(ii)

assi

mila

tion

;1

1(b)

(iii)

any

two

from

:an

tibod

ies 

/ ins

ulin

 / gl

ucag

on / 

fibrin

(oge

n) / 

haem

oglo

bin 

/ AV

P e.

g. e

nzym

e(s)

(in

pha

gocy

tes)

;;

2

1(c)

an

y fo

ur fr

om:

(cho

lera

bac

teria

) pro

duce

a to

xin

;to

xin

caus

es s

ecre

tion

of c

hlor

ide

ions

;in

to s

mal

l int

estin

e ;

low

erin

g w

ater

pot

entia

l ;m

ovem

ent o

f wat

er in

to th

e gu

t ;by

osm

osis

;re

sults

in d

iarr

hoea

;

4

0610

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CS

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Mar

k S

chem

e Fo

r exa

min

atio

n

SPEC

IMEN

fro

m 2

023

Pag

e 6

of 1

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0

Que

stio

nA

nsw

erM

arks

Gui

danc

e

2(a)

chem

ical

sub

stan

ce p

rodu

ced

by a

(end

ocrin

e) g

land

;ca

rrie

d by

the

bloo

d ;

alte

rs th

e ac

tivity

of s

peci

fic ta

rget

org

ans 

/ AW

;

3

2(b)

(i)13

6(%

) ;;;

3M

P1

for c

orre

ct re

adin

gs fr

om th

e gr

aph,

72

and

170

MP

2 fo

r cor

rect

cal

cula

tion

MP

3 fo

r cor

rect

roun

ding

to a

who

le n

umbe

rec

f MP

2 an

d M

P3

from

inco

rrec

t MP

1

2(b)

(ii)

any

thre

e fro

m:

sim

ilar r

espo

nse

first

30

min

utes

 / AW

; in

crea

ses 

/ dec

reas

es, m

ore

stee

ply 

/ fas

ter :

incr

ease

s to

 / ha

s, a

hig

her c

once

ntra

tion

;re

ache

s a

peak

 / de

crea

ses,

(muc

h) la

ter ;

does

not

retu

rn to

, sta

rting

con

cent

ratio

n / o

rigin

al v

alue

 / no

rmal

 / AW

;an

y co

mpa

rativ

e us

e of

figu

res

with

cor

rect

uni

ts ;

3or

a th

roug

hout

2(b)

(iii)

any

four

from

: in

crea

se in

glu

cose

con

cent

ratio

n ca

uses

sec

retio

n of

insu

lin ;

(sec

retio

n) b

y th

e pa

ncre

as ;

insu

lin c

ause

s th

e liv

er to

take

up

gluc

ose

from

the

bloo

d ;

gluc

ose

is c

onve

rted

to g

lyco

gen

;AV

P ; (

e.g.

ref.

to d

etec

tion

of in

crea

sed

gluc

ose

by th

e pa

ncre

as / 

activ

atio

n of

enz

ymes

in th

e liv

er)

4

2(b)

(iv)

any

two

from

:ta

king

of i

nsul

in ;

ref.

to in

ject

ions

 / pu

mp

;(r

egul

ar) m

onito

ring

of b

lood

glu

cose

con

cent

ratio

n ;

cont

rolli

ng c

arbo

hydr

ate

inta

ke ;

AVP

; e.g

. exe

rcis

e re

gula

rly / 

mai

ntai

n a

heal

thy

mas

s / i

dea

that

insu

lin

cann

ot b

e ta

ken

oral

ly

2

0610

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IMEN

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0

Que

stio

nA

nsw

erM

arks

Gui

danc

e

3(a)

red

bloo

d ce

ll:ap

pear

ance

:bi

conc

ave

(dis

c / s

hape

) / n

o nu

cleu

s /

red

bloo

d ce

lls s

mal

ler t

han

(nam

ed) w

hite

blo

od c

ell(s

) / o

ra ;

func

tion:

trans

ports

oxy

gen

;

lym

phoc

yte:

appe

aran

ce:

little

cyt

opla

sm / 

larg

e(r)

nuc

leus

 / nu

cleu

s fil

ls m

ost o

f the

cel

l ;fu

nctio

n:re

f. to

act

ive

imm

unity

 / re

spon

ds to

, ant

igen

(s) o

r vac

cine

(s) 

/ pro

duce

s an

tibod

ies 

/ ref

. to

mem

ory

cells

;

phag

ocyt

e:ap

pear

ance

:lo

bed 

/ irr

egul

ar-s

hape

d / C

-sha

ped 

/ AW

, nuc

leus

;fu

nctio

n:en

gulf

path

ogen

s / p

hago

cyto

sis 

/ AW

;

6

A tr

ansp

orts

car

bon

diox

ide

3(b)

(i)fib

rinog

en →

fibr

in ;

1

3(b)

(ii)

prev

ent b

lood

loss

;pr

even

t ent

ry o

f (na

med

), pa

thog

ens 

/ mic

robe

s ;

2

3(c)

(i)(P

) XHXh ;

(Q) X

h Y ;

(R) X

HY

;

3

3(c)

(ii)

0.25

;1

3(c)

(iii)

gene

is lo

cate

d on

a s

ex c

hrom

osom

e ;

char

acte

ristic

is m

ore

com

mon

in / 

one

sex

(than

the

othe

r) ;

2

0610

/04

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4(a)

C6H

12O

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6H

2O +

6C

O2

;;2

MP

1 co

rrec

t sym

bol e

quat

ion

MP

2 co

rrec

t bal

anci

ng o

f the

equ

atio

n

4(b)

su

gar b

eet ;

max

. tw

o fro

m:

idea

that

it g

row

s in

an

appr

opria

te te

mpe

ratu

re ra

nge

;id

ea th

at it

gro

ws

in a

n ap

prop

riate

rain

fall

rang

e ;

ener

gy y

ield

is g

reat

er th

an, w

heat

 / co

rn ;

use

of d

ata

to s

uppo

rt an

swer

;

3ec

f MP

2 an

d M

P3

from

inco

rrec

t MP

1

4(c)

any

thre

e fro

m:

incr

ease

d ra

te o

f tra

nspi

ratio

n ;

grea

ter c

once

ntra

tion

of w

ater

vap

our i

nsid

e th

e le

af th

an o

utsi

de ;

mor

e w

ater

vap

our d

iffus

es o

ut o

f the

leaf

;th

roug

h st

omat

a ;

mor

e w

ater

mov

es u

p, th

e xy

lem

 / by

tran

spira

tion

pull

;

3

4(d)

any

thre

e fro

m:

ref.

to a

sexu

al re

prod

uctio

n ;

min

imis

es g

enet

ic v

aria

tion 

/ giv

es a

uni

form

cro

p / A

W ;

prod

uces

pla

nts

that

all

have

the

sam

e fe

atur

es / 

AW ;

ensu

res

cons

iste

ncy

of p

rodu

ct / 

AW ;

AVP

; e.g

. fas

ter p

rodu

ctio

n fro

m c

uttin

gs th

an fr

om s

eeds

3

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caly

ski

n ;

leat

hery

 / so

ft-sh

elle

d, e

ggs

;2

5(a)

(ii)

any

two

from

: ce

llulo

se / 

cell

wal

l ;ch

loro

plas

t / c

hlor

ophy

ll ;

(larg

e / p

erm

anen

t / c

entra

l) va

cuol

e ;

2

5(b)

(i)m

outh

;sm

all i

ntes

tine

;2

5(b)

(ii)

any

thre

e fro

m:

corr

ect r

ef. t

o ac

tive

site

;ac

tive

site

mus

t be

com

plem

enta

ry s

hape

to, s

ubst

rate

 / st

arch

;to

mak

e en

zym

e –

subs

trate

com

plex

 / to

allo

w s

ubst

rate

to b

ind

to e

nzym

e ;

ref.

to o

nly

fits

one

subs

trate

 / sp

ecifi

c to

one

sub

stra

te ;

3

0610

/04

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ge IG

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chem

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r exa

min

atio

n

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fro

m 2

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stio

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danc

e

5(c)

any

five

from

: ca

ptiv

e br

eedi

ng p

rogr

amm

e ;

in z

oos 

/ res

erve

s ;

artif

icia

l ins

emin

atio

n / I

VF 

/ AW

;to

, bui

ld u

p nu

mbe

rs / 

rele

ase

back

to th

e w

ild ;

seed

ban

ks ;

in b

otan

ic g

arde

ns / 

othe

r nam

ed ;

stor

e se

eds

for l

ong

perio

ds ;

educ

atio

n / a

war

enes

s ;

legi

slat

ion

;to

, pro

tect

 / re

stor

e, h

abita

ts ;

to, r

educ

e / p

reve

nt, p

ollu

tion

;to

, res

trict

 / pr

even

t, in

trodu

ced

spec

ies

;to

, res

trict

 / pr

even

t, hu

ntin

g / f

ishi

ng ;

mon

itorin

g po

pula

tions

;to

, det

ect d

ecre

ases

or i

ncre

ases

 / de

term

ine

quot

as ;

AVP

; e.g

. pro

tect

ed a

reas

suc

h as

, nat

iona

l par

ks / 

natu

re re

serv

es / 

mar

ine

park

s

5

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nam

e of

org

anis

m fr

om F

ig. 6

.1

prod

ucer

alga

e / (

phyt

o)pl

ankt

on ;

seco

ndar

y co

nsum

er(s

tone

) cra

b / m

ysid

shr

imp 

/ ble

nny

;

an a

nim

al th

at fe

eds

at tw

o tro

phic

leve

lsbl

enny

 / (s

potte

d) s

andp

iper

;

3

6(b)

(i)ni

trific

atio

n ;

(nitr

ifyin

g) b

acte

rium

 / ba

cter

ia ;

2A

oxi

datio

n

6(b)

(ii)

any

thre

e fro

m:

root

hai

rs ;

(by)

act

ive,

tran

spor

t / u

ptak

e ;

acro

ss (c

ell)

mem

bran

es ;

agai

nst a

con

cent

ratio

n gr

adie

nt / 

low

to h

igh

conc

entra

tion 

/ AW

;by

pro

tein

s (m

olec

ules

 / pu

mps

 / ca

rrie

rs) ;

use

of, e

nerg

y / A

TP ;

(als

o by

) diff

usio

n ;

3

6(b)

(iii)

ribos

ome

;1

6(b)

(iv)

nitro

gen

fixat

ion

;1

6(c)

any

thre

e fro

m:

ener

gy is

lost

bet

wee

n th

e tro

phic

leve

ls / 

AW ;

not e

noug

h en

ergy

, at t

he to

p of

the

pyra

mid

 / at

hig

her t

roph

ic le

vels

, to

supp

ort a

larg

e nu

mbe

r of o

rgan

ism

s ;

nam

ed e

xam

ple

of h

ow e

nerg

y is

lost

;no

t all

orga

nism

s / p

arts

of o

rgan

ism

s (in

one

trop

hic

leve

l), a

re,

eate

n / d

iges

ted

;

3

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brid

ge IG

CS

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e Fo

r exa

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atio

n

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BLA

NK

PA

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