igcse review sec 3 material

5/18/2018 IGCSE Review Sec 3 Material

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IGCSE REVIEW: SECONDARMATERIAL


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CHAPTER 1: INTRO TO LIFE


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WHAT ARE THE 7 CHARACTERISTICSLIFE?

Nutrition: the process in which an organismtakes in food and converts it to protoplasm

Excretion: the removal of metabolic wastes and

substances in excess of requirement


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Respiration: the chemical reactions that breakdown nutrient molecules to release energy

Growth: permanent increase in the size and dry

mass of an organism by increasing cell numbe

or cell size or both !evelopment "making anorganism more complex#


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$ovement: an action by an organism causes a c

in position or place

Reproduction: the process that makes more of t

same kind of organism

%ensitivity: able to react to changes in the envir


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BINOMIAL SYSTEM

&he 'atin name of an organism


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BINOMIAL SYSTEM

Example: (hat is the genus and speciescholera bacterium Vibrio cholerae)


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CLASSIFICATION OF ORGANISMS

rganisms can be organized into groups bahared similar features

he largest grouping is the kingdom and th

s the species

e need to know common features of four hyla as well as classes of arthropods and v

chordata#+ microorganisms+ and ,owering


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MAIN FEATURES OF MICROORGANIS

-acteria: capsule shaped with cell walls+ free ,o

!N.

/irus: 0ust a protein coat

1ungus: animal and plant characteristics+ form h"thread like structures# to absorb food 1ungi rep

by releasing spores which travel in the wind


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3 IMPORTANT INVERTEBRATE PHY

.nnelids: worms with soft bodies made up of se

"like earthworms#

Nematodes: no segments 2 microscopic worms+

digestive system

$olluscs: 3ave soft bodies that are not segment

have a muscular 4foot5 that is used for burrowin

movement %ome may have a shell for protectio

predators or to prevent water loss


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ANNELID (GROSS)


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NEMATODE (ALSO GROSS)


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ARTHROPODS:&his is the largest phylum in the animal kingdom

arthropods have a segmented body+ an exoskele

and 0ointed legs6lasses within the phylum .rthropoda include:

78nsects: body divided into head+ thorax and abd9 pairs of legs+ antennae+ can have wings

6rustaceans: body divided into cephalothorax "hthorax# and abdomen+ have two pairs of antenn

compound eyes &hey breathe using gills


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ARTHROPODS: .rachnids: body segments "cephalothorax and

abdomen#+ ; pairs of legs

$yriapods: many segments to the body+ many p

legs &hese are the fast2moving+ carnivorous

centipedes+ and slow2moving herbivorous millip


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INSECTS


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CRUSTACEANS


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ARACHNIDS


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MYRIAPODS


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VERTEBRATES:.nimals that have a backbone are called vertebra

&he


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FEATURES OF VERTEBRATE PHYLU

$ammals: 3air=fur+ lactate "produce milk#

blooded

1ish: gills+ lay eggs+ have scales

Reptiles: %cales+ cold blooded+ lay eggs

-irds: lay eggs+ have feathers

.mphibians: breath through skin+ lay eggs


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FLOWERING PLANTS:6otyledon

. cotyledon is a leaf of the embryo of a seed 8t i

lants can either have amonocotyledon "single seed leaf# or a dicotyledo"double seed leaf# and ,owering plants are classsuch


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MONOCOTS VS DICOTS:

$onocotyledons

>arallel veins in leaves

>etals and ,ower parts in multiples of 9

Roots are shallow and etals and ,ower parts in multiples of ; or ?

Roots are branched but taproot based


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MONOCOTS VS DICOTS:


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MONOCOTS VS DICOTS:


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MONOCOTS VS DICOTS:


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DICHOTOMOUS KEY


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CHAPTER 2 CELLS


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WHAT IS A CELL

&he most basic building block of living

organisms


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CELLULAR ORGANELLES

6ell membrane @ %electively permeable 6ontsubstances entering or leaving the cell

6ytoplasm @ &he part of the protoplasm betwe

the cell surface membrane and the nucleus cell activities occur here

Nucleus @ 6ontains !N. 6ontrols cell activitie

cell division


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CELLULAR ORGANELLES

6ell (all @ 1ully permeable >rotects the cein0ury >revents plants cells from bursting

Rough endoplasmic reticulum @ 6ontainsribosomes and transports proteins to the apparatus

Ribosomes@ >rotein synthesis


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CELLULAR ORGANELLES

%mooth endoplasmic reticulum @ !oes not haribosomes attached %ynthesizes fats

Golgi apparatus @ $odi "energy# by cellular

respiration


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CELLULAR ORGANELLES

6hloroplasts @ 6arry out photosynthesis

/acuole @ %tores substances within the cell

6entrioles@ 3elp in nuclear division


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CELLULAR ORGANELLES

'ysosomes@ break down harmful substance

Nucleoulus @ %ynthesizes ribosomes

1lagellum=6ilia @ 3elp in movement


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ANIMAL CELLS


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PLANT CELL


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SPECIALIZED CELLS AND THEIRFUNCTIONS

6iliated cells @ 8n respiratory tract Removes mucushas trapped bacteria and dust 3ave many mitocho

for movements

Root hair cells @ .bsorption 3elp to greatly increas

surface area of roots 3ave mitochondria for activetransport of ions

Aylem vessels: 2 6onduction and transport $issing

organelles to allow easy ,ow of substances


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SPECIALIZED CELLS AND THEIRFUNCTIONS

$uscles cells @ 6ontraction 3ave many mitocho

Red blood cells @ &ransport No nucleus -iconca

shape


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TISSUES VS ORGAN VS ORGAN SYST

6ell: individual cell performing a speci


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CALCULATING MAGNIFICATION


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CHAPTER 3: TRANSPORT

&hree main types of transport !iBusion

*smosis

.ctive &ransport


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DIFFUSION

&he net movement of molecules from a reof their higher concentration to a region o

lower concentration down a concentration

gradient+ as a result of their random move

Ex !iBusion of perfume molecules


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FACTORS THAT AFFECT THE RATEDIFFUSION

%urface area of diBusion @ Greater surface arfaster diBusion

%teepness of concentration gradient @ %teep

gradient C faster diBusion

!istance @ %horter distance C faster diBusion

%ize of molecules @ %maller molecules diBuse

&emperature @ 3igher temperature C more E


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OSMOSIS $ovement of water from an area of high

water potential to an area of low waterpotential+ across a partially permeable

membrane

Ex (ater entering a root hair cell


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WATER POTENTIAL

(ater potential is the tendency of water to mosmosis from one place to another

. dilute solution "eg+ distilled water# has lots

available water and therefore a high water . concentrated solution "eg+ D$ salt solutilittle available water and therefore a low wpotential


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WHAT HAPPENS TO CELLS WHEN PLAIN SOLUTIONS?

>lacing a cell in a solution of higher water pote- (ater rushes inside the cell

- .nimal cell may burst+ plant cell may become

>lacing a cell in a solution of lower water pote

- (ater rushes out of the cell

- .nimal cell may shrink and die+ plant cell bec,accid or plasmolysed


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ACTIVE TRANSPORT Fsing energy to transport a substance

against the concentration gradient


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ACTIVE TRANSPORT Ex Root hair cells or villi taking in

substances

what makes these cells able to perform

active transport)

$any mitochondria for .&>

%pecial carrier proteins in the cell membrane


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SUMMARY OF TRANSPORT


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CHAPTER 4: NUTRITION


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WHAT IS NUTRITION?

&he taking in of nutrients which are organic suband mineral ions+ used for energy+ growth or tiss

repair


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CARBOHYDRATES = SUGARS

%imple 6arbohydrates

Glucose "monosaccharide C one unit#

!isaccharidesC two units

%ucrose+ $altose+ 1ructose


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CARBOHYDRATES CONT..

>olysaccharidesC many glucose molecules

%tarch: Energy storage in plants

Glycogen: Energy storage in animals


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CARBOHYDRATES CONT..

>olysaccharidesC more then D

6ellulose %tructural support in plants 1ound incell walls


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FATS

$ade of sub units: Glycerol and fatty acids


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FATS

Fsed for storage Fsed for the production of cholesterol

Fsed for the production of cell membranes

"phospholipidsC tails instead of 9#


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PROTEINS

$ade of .mino acids 1orms long chains called

>olypeptides

"forms peptide bonds#

Fsed for structural support

and enzymes


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TESTING FOR NUTRIENTS

%tarch C iodine test "Neg @ brown+ >os @ blue=bla Reducing sugars C -enedicts test "Neg @ blue+

green+ yellow+ orange+ brick red#

>roteins C -iuret test "Neg @ blue+ >os @ purple#

1ats C Ethanol emulsion test "Neg @ clear+ >os @


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MAIN SOURCES (QUICK) 6arbohydrates 2 rice+ pasta+ grains

1ats 2 meat or animal related products+ or plant

>roteins 2 meats or legumes

/itamin 62 citrus fruits

/itamin !2 %unlight and !airy products

6alcium2 $ilk

8ron 2 red meat

1ibre "roughage# @ -ran cereals+ cabbage

DEFICIENCYSYMPTOMS


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DEFICIENCY SYMPTOMS

/itamin 6: scurvy "bleeding gums#

/itamin !:2 Rickets !isease "softening of bones#

6alcium: osteoporosis "brittle bones and teeth#

8ron: .nemia "tiredness+ lack of energy#


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MALNUTRITION

%tarvation "not getting enough nutrients# 6oronary heart !isease "Not getting appropriate f

may lead to stress=increased blood pressure#

6onstipation: Not enough


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BALANCED DIET

-alanced !iet: 6hoosing from a wide variety of with appropriate portions of each consumed eve


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BALANCED DIET REQUIREMENTS

!epends on .ge !epends on Gender

!epends on .ctivity of an 8ndividual

MICROORGANISMSINTHEFOODINDU


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MICROORGANISMS IN THE FOOD INDU

Ioghurt is made using bacteria that break down

in milk anaerobically into lactic acid -read making involves yeast which releases 6*

causes the bread to rise

-acteria are used in production of wine and bee

FOODADDITIVES


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FOOD ADDITIVES

1ood additives can colour+ preserve and add ,avo

our food.dvantages include: 1ood looks more appealing+ lasts longer+ food tastes better

!isadvantages include: 6arcinogens+ provoke astattacks and hyperactivity in children+ head achenausea

ENZYMES BIOLOGICALCATALYST


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ENZYMES: BIOLOGICAL CATALYST

WHATISANENZYME


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WHAT IS AN ENZYME

. catalyst is a substance that speeds up a chemreaction and is not changed by the reaction

6atalysts lower the activation energy needed fo

reaction to occur

Enzymes are biological catalysts "1ound in livingthings#

ENZYMESARESPECIFIC


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ENZYMES ARE SPECIFIC

Enzymes are very speci


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ENZYME SPECIFICITY

Enzymes are not only speci


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ACTIVITY

.t low temperatures enzymes display little activ

.s temperature increases enzyme activity incre

the enzyme has more kinetic energy "faster coll

.t high temperatures the enzyme completely

denatures &he bonds that hold its speci


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EFFECT OF TEMPERATURE ON ENZY

EFFECTSOFPHONENZYMEACTIV


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EFFECTS OFPH ON ENZYME ACTIV

.t too low or too high p3 levels+ the enzyme willcompletely denature

Enzymes have an optimal temperature and p3 tha

work best at

Enzymes in the stomach work best at acidic p3 En

in the body generally work best at 9LM6 "body

temperature#

EFFECTOFPHONENZYMES


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EFFECT OF PH ON ENZYMES

ROLESOFENZYMESININDUSTRY


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ROLES OF ENZYMES IN INDUSTRY

1ermentation processes -iological (ashing powders

$edicine "ex >enicillin#

FERMENTATIONOFBACTERIA


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FERMENTATION OF BACTERIA

-acteria are placed in a fermenter and supplied wglucose+ amino acids+ oxygen and optimal tempand p3

-acteria multiply and produce many enzymes

Enzymes are extracted by


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USE OF ENZYMES IN WASHING POWD

&he enzymes extracted from the fermenter can bto break down insoluble substances into solublesubstances

>roteases: >rotein 2 amino acids

'ipases: 1ats 2 glycerol and fatty acids

$altase: %tarch 2 glucose

%oluble products wash away easily

CHAPTER6:HUMANALIMENTARYCA


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CHAPTER 6: HUMAN ALIMENTARY CA

IMPORTANTTERMS


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IMPORTANT TERMS

8ngestion: &aking of food and drink into the body throug

mouth

Egestion: >assing food that has not been digested as fa

!igestion: break down of large+ insoluble food molecule

small+ water soluble food molecules so that they can be

into the blood stream

.bsorption: the movement of digested food through th

the small intestine into the blood

.ssimilation: movement of digested food molecules int

IMPORTANTENZYMES


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IMPORTANT ENZYMES

>rotein is made of amino acids

>roteases "eg >epsin# break down protein into amino

%tarch is made up of glucose

6arbohydrases "eg .mylase# break down starch into

1ats are made of glycerol and fatty acids

'ipases break down fat into glycerol and fatty acids

DIGESTIVESYSTEM


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DIGESTIVE SYSTEM

&he alimentary canal includes the mouth+ pharynx

oesophogus+ stomach+ the small intestine "duoden

0e0unum and ileum#+ the large intestine "colon and

and the anus

&he organs associated with the gut include the livpancreas and gall bladder

FUNCTIONS OF ALIMENTARY SYSTE


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FUNCTIONS OF ALIMENTARY SYST


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O 'iver+ Gall b>ancreas

PHYSICAL AND MECHANICAL DIGEST


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>hysical digestion:

8nvolves the mechanical break2up of food into small pa&his increases the surface area for enzymes to act

Examples: 6hewing in the mouth+ peristalsis+ contractithe stomach

6hemical digestion:

8s the breaking down of large insoluble molecules in fosmall soluble molecules which can be absorbed &his hydrolytic reactions catalyzed by enzymes

ROLE OF THE MOUTH


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6hewing breaks the food into smaller pieces inc

the surface area

%aliva softens the food and salivary amylase dig

starch to maltose

&he tongue pushes food "now called bolus# into pharynx

ROLE OF THE PHARYNX


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1ood travels from the mouth to the oesophagus

through the pharynx

1ood is prevented from entering the lungs by a ,

the larnyx called the epiglottis

ROLE OF THE OESOPHAGUS


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-olus moves from the phayrnx to the stomach b

oesophagus by peristalsis

&he wall of the oesophagus constricts "circular m

contract+ longitudinal muscles relax# behind theand relax "circular muscles relax+ longitudinal m

contract# in front of the bolus


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PERISTALSIS

PERISTALSIS


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ROLE OF THE STOMACH


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&he stomach secretes gastric 0uice+ and holds fo

92; hours

>eristalsis churns food and mixes it with gastric

Gastric 0uice contains dilute 36l which denature

amylase and activates the enzyme pepsin >epsin breaks down proteins into amino acids

&he pyloric sphincter opens to allow food "now c

chyme# to pass to the small intestine

ROLE OF THE SMALL INTESTINE


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(hen food enters the small intestine

&he pancreas releases pancreatic 0uice containin

amylase+ trypsin and lipase

&he gall bladder releases bile which emulsi


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>rotein+ starch and fat are digested in the small

intestine

(ater and digested food are absorbed in the sm

intestine by microvilli

$icrovilli contain a thin epithelium+ blood capillaand a lymphatic vessel called the lacteal

&he small intestine transports nutrients directly

liver via the hepatic portal vein

ABSORPTION OF FOOD


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ROLE OF THE LARGE INTESTINE


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No digestion occurs in the large intestine

&he main role is to absorb water and mineral sa

the undigested food materials

ROLES OF THE LIVER (PLAYS A LARROLEINASSIMILATION)


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ROLE IN ASSIMILATION)

6onvert glucose to glycogen

>roduce bile to be sent to the gall bladder for st

6onvert amino acids to proteins and excess am

acids to urea "deamination#

-reakdown hormones+ alcohol and toxins

6onverts fatty acids and glycerol into fat

>roduces cholesterol from fats

ROLE OF THE PANCREAS


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&he pancreas produces pancreatic 0uice containing a

trypsin and lipase

>ancreatic 0uice enters the duodenum via the pancre

duct

&he pancreas secretes the hormones insulin and glu

to regulate blood glucose levels

ROLE OF THE GALL BLADDER


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%torage of bile that has come from the liver

Releases bile into the duodenum through the bi

TEETH


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>urpose: &o break large food particles into small

particles "small enough to be swallowed#

8ncisors @ chisel shaped for biting and cutting

6anines @ pointed for piercing and tearing

>remolars @ uneven cusps for grinding and chew

$olars @ like premolars for chewing the food


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TOOTH


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!ivided into the crown and the root

6rown "above the gums#

- 6ontains enamel+ dentine and pulp cavity

Root "in the gums#

2 6ontains cement+ nerves and blood vessels

TYPES OF HUMAN TEETH


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TOOTH DECAY AND REPAIR


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&ooth decay is caused by bacteria in your mouth

mix with saliva to form plaque

-acteria in plaque respire anaerobically to produ

which attacks the enamel of the tooth

-rushing with 1louride strengthens the enamel o

teeth

CHAPTER 7: NUTRITION IN PLANT


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WHAT IS PHOTOSYNTHESIS


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>hotosynthesis: &he fundamental process in wh

plants manufacture carbohydrates

LIMITING FACTOR


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&he substance+ whose concentration is preventin

growth= chemical reactions to occur

FACTORS THAT CONTROL THE RATEPHOTOSYNTHESIS/ GROWTH OF A PL


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6* concentration

'ight intensity

&emperature

(ater .vailability

8on concentrations

DESIGNING EXPERIMENTS


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$ake sure all factors are kept constant "like the

control#+ all experimental setups have one facto

changed "ex &emperature+ p3+ light intensity#

GREEN HOUSES


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6an control environment to create optimal grow

conditions

6an grow food all year round

6an be costly= have a negative impact on theenvironment

LEAVES


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'eaves have a large surface area to absorb light

thin shape for eHcient gas exchange+ many

chloroplasts to maximize photosynthesis+ veins

support the leaf surface and transport sucrose+

and ions

LEAF STRUCTURE


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IMPORTANCE OF CERTAIN NUTRIEN

>lants require:


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q

$agnesium to make chloropyll $agnesium deroduce little or no xylem

No root hair cells

No waxy cuticle

3ave extensive system of air spaces in their ste

gas exchange

TRANSLOCATION

h f d i id h


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&he movement of sucrose and amino acids thro

phloem "multidirectional#

Goes form sources to sinks

- %ource @ region of production or storage "eg 'e

- %ink @ region of use "eg 1ruit+ seeds+ roots#

8mportant for the transport of pesticides

TRANSLOCATION


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EXPERIMENTS FOR XYLEM AND PHL

A l t t ( t l bl d


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Aylem tests: (ater soluble dye

>hloem: radioactive ions+ 4ringing5 the tree

CHAPTER 8: TRANSPORTATION IN HU


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DOUBLE CIRCULATORY SYSTEM

>ulmonary system 3eart 'ungs 3eart "carrie


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>ulmonary system: 3eart 'ungs 3eart "carrie

to get oxygen#

%ystemic system: 3eart -ody 3eart "carries o

to muscles#

-lood passes through the heart two times in one

complete circulation

HEART DIAGRAM


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VALVES


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HEART BEAT

D# .trial systole "contraction# -oth atria contrac


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D# .trial systole "contraction# 2 -oth atria contrac

ventricles with blood -icuspid and tricuspid valpushed open

# /entricular systole @ both ventricles contract pblood into the aorta and pulmonary artery -icusand tricuspid close+ while semilunar valves open

9# /entricle diastole "relax# @ ventricles relax andheart re


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COMPONENTS OF BLOOD

Red -lood cells "Erythrocytes#2 transport oxygen no n


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Red -lood cells "Erythrocytes# transport oxygen+ no n

contain haemoglobin (hite -lood cells ">hagocytes and lymphocytes#2 imm

system @ phagocytosis and production of antibodies

>lasma: mostly water+ transport of ions and soluble n

>latelets: 3elps cause clotting "


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CROSS-SECTION OF AN ARTERY

The arteries carry blood at high

pressureaway from the heart.

Looking at the cross-section of

an artery, why is it suitable for


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thick outer wall

thick inner layer

of muscle and

elastic fibres

Narrow

lumen

carrying blood at high pressure?

The veins carry blood at low

pressureback into the heart.


a vein, why is it suitable for

CROSS-SECTION OF A VEIN


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y

carrying blood at low pressure?

thin outer wall

thin inner layer

of muscle and

elastic fibres

wide

lumen

CROSS-SECTION OF A CAPILLARY

The capillaries carry blood to and

from the bodys cells.


a capillary, why is it suitable for


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the echange of substances

between the blood and body cells?

MAIN VESSELS

Kidneys: Renal .rtery and /ein


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Kidneys: Renal .rtery and /ein

%tomach: .rtery to gut+ hepatic portal vein "direcliver#

'iver: 3epatic artery and /ein

'ungs: >ulmonary .rtery and /ein

3eart: .orta and /ena cava

CORONARY HEART DISEASE

-lockage of the arteries of the heart


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oc age o e a e es o e ea

6aused by deposits of fatty tissues "cholesterol#

atherosclerosis

6an cause heart attacks

CAUSES/PREVENTION

6auses: %tress+ unhealthy diet+ inactivity+ genet


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+ y + y+ g

>revention: eat healthy+ exercise+ stress contro

TISSUE FLUID

>lasma and white blood cells exit capillaries and


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p

space around tissues as tissue ,uid 3elps supply these tissues with nutrients

'eaves capillaries on artery side due to high pre

"can re2enter on venial side#

LYMPHATIC SYSTEM

Not all tissue ,uid returns via capillaries


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p

%ome must enter lymphatic system "separate vessystem: not a circulatory system#+ once in lympha

system the ,uid is now called lymph

3elps to absorb fats from small intestines and co

many lymphocytes "very important for immune s

CHAPTER 10: RESPIRATION IN HUM


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WHAT IS RESPIRATION

Respiration is the chemical reactions that break


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nutrients to release energy Fses for energy: protein synthesis +muscle contr

cell division+ active transport+ growth+ the passa

nerve impulses and maintenance of the bodys

temperature

AEROBIC RESPIRATION

Release of large amounts of energy in the prese

oxygen


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ANAEROBIC RESPIRATION

Release of a small amount of energy in the absence of

8n muscles


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without *

'ater:

ANAEROBIC RESPIRATION: YEAST


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STRUCTURE OF GAS EXCHANGE SYS

.ir from the environment travels through:


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D trachea bronchi

$any bronchioles

$illions of alveoli

LUNGS


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ALVEOLI


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PURPOSE OF DIAPHRAGM AND RIB

!iaphragm contracts and makes your chest cavit

8nternal intercostal muscles "muscles in between


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8nternal intercostal muscles "muscles in between

relax while external intercostal muscles contract

"antagonistic muscles#

Ribs move up and outwards further increasing th

cavity "chest# volume

8ncrease in volume of chest cavity decreases pres

.ir from atmosphere enters the lungs

*pposite for exhaling

COMPOSITION BETWEEN INHALED AEXHALED AIR

8nhaled .ir: *xygen C DP+ 6arbon dioxide C 9P


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Exhaled .ir: *xygen C DQP+ carbon dioxide C ;P

Gas exchange is possible due to diBerence in concen

(ater vapor concentration and temperature is also a

HOW ARE LUNGS ADAPTED FOR GAEXCHANGE?

Numerous alveoli for large surface area of gas ex


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.lveolar walls are one cell thick for short distanc

.lveoli are richly supplied with blood capillaries t

steep * and 6* concentration gradients

.ir is warmed and moistened when entering the

speeding up rate of diBusion

.lveoli have a thin


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%ize

'ifestyle "like smoking and eating habits#

Gender

.ge

Exercise "p3 and carbon dioxide concentration#

TESTING FOR PRESENCE OF CARBDIOXIDE

'imewater test "cloudy in presence of carbon di


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8f there is too much 6arbon dioxide in your blood

becomes acidic and using a hydrogen carbonate

indicator we can see if the blood is acidic or not

C acidic+ purple C alkaline redCneutral#

ROLE OF MUCUS AND CILIA

$ucus: &o help trap dust particles


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6ilia move the mucus upward towards the esophagthe mucus can be swallowed and all dirt particles anpathogens can be destroyed

CHAPTER 11: EXCRETION


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WHAT IS EXCRETION

Excretion: the removal of toxic materials+ waste


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products of metabolic processes+ or substances excess of requirement+ from the body

Ex: carbon dioxide+ urea+ salts

FUNCTIONS OF KIDNEY

Frine formation


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Regulation of blood pressure

%ecretion of hormones

FUNCTION OF KIDNEYS


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URINE PRODUCTION

%tep D# Fltra


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capsule#

%mall molecules in the blood leave the blood plasthrough holes in the basement membrane of theglomerulus &his ,uid is called the


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tubule#

Fseful substances such as all glucose+ all amino asome water and some mineral salts are taking binto the blood

2 $ost urea and other waste products remain in t

nephron to be passed to the urinary bladderKidney 2 Freter 2 Frinary bladder 2 Frethra

OSMOREGULATION

*ccurs in the collecting duct:

- 'ow water potential in the blood causes the


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hypothalamus in the brain to cause the pituitaryto release .!3

- .!3 makes the walls of the collecting duct morepermeable to water

-$ore water is taken from the


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EXCESS SALT OR PROTEINS IN DIE

Excess salts will result in a very low water poten


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the blood plasma $ore .!3 will be released anlarger volume of water will be reabsorbed into t

blood plasma &his will cause high blood pressu

Eating lots of proteins will mean the liver breaks

many excess amino acids by deamination to forGreater urea production means the urine will co

large amount of urea and be very concentrated

KIDNEY FAILURE - DIALYSIS

$aintaining blood glucose and protein levels+ as


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dialysis machine removes urea from the blood s

&he dialysis ,uid is specially controlled "exampl

equal glucose concentration to a healthy person

&he dialysis tube has a semi2permeable wall

&he dialysis ,uid and blood ,ow in opposite dire

KIDNEY TRANSPORT VS DIALYSIS

1actors to think about:

6ost


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6ost

&issue re0ection

.vailability of kidneys

>ermanent vs temporary solution

Risks of surgery

&ime consuming=aBects a persons life


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GOOD LUC


176/176

THE END!!!!!

igcse review sec 3 material

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