BIOLOGY FORM 4 CHAPTER 6: NUTRITION WHAT IS NUTRITION?
The process that organisms obtain energy from food, for growth, maintenance and repair of damage tissue TYPES OF NUTRITION
1) Autotrophs (self, feed) Photosynthesis (Green plants) Chemos Chemosyn ynthe thesis sis (Bact (Bacteri eria a synth synthesi esis s organ organic ic compo compoun unds ds by oidis oidising ing inorg inorgani anic c compounds ! ammonia) • •
") #eterotrophs (cannot synthesise their own food) #olo$oic (#erbi%ours, Carni%ours & 'mni%ours) aprophytic ('rganisms fed on dead decaying matter Parasitic ('rganisms obtains nutrient by li%ing on in the body of other li%ing organisms • • •
BALANCE DIET
1* Balan Balance ce diet+ diet+ a diet diet which which contain contains s the right right amoun amounts ts of carbo carbohyd hydrat rate, e, protei proteins, ns, fat, %itamins, mineral, water and fibers* "* #ealth #ealthy y diet+ diet+ shoul should d pro%id pro%ide e the the body body with with all the substa substance nces s nece necessa ssary ry to maint maintain ain growth, to eep good health and repair damage tissue*
WHAT ARE THE FACTORS THAT EFFECTING THE DAILY ENERGY REQUIREMENT?
1* Climate!C Climate!Colde olderr place need need more energy energy to maintain maintain body body temp* becaus because e of the loss of energy to the surrounding* "* Body Body si$e ! The smaller smaller perso person n ha%e a larger larger surfac surface e per unit %olume %olume compa compare re to a larger person, the rate of heat loss is higher, they need more energy* -* Gender Gender ! .ale need more more energy energy because because they they are more acti%e acti%e & the metaboli metabolic c rate is higher than female* /* Growing children children ha%e ha%e higher metabolic rate rate than older older people* people* They need more energy* energy* 0* 'ccupati 'ccupation on ! Person does does hea%y wor wor needs needs more energy energy than a person person who is only moderately acti%e* NUTRIENTS IN FOOD
1* Carbohyd Carbohydrate rates+ s+ (rice, (rice, noodles noodles,, potato potatoes) es) ource of energy for motion and growth sed to form supporting structures in plants (cell wall) 2ffecti%e methods for food storage (starchglycogen) Part of nucleus (34A) 5ac of it + become %ery wea • • • • •
"* Proteins Proteins + (meat, (meat, fish, fish, cheese cheese,, eggs) eggs) .ae new cells for growing •
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6epair & 6eplace damaged cellstissues .ae en$ymes, antibodies & hormones 5ac of it+ washioror, %ery wea, muscle are poorly de%eloped
-* 7at + ( oils, butter, mil, nuts) upply energy Part of cell membrane #elp absorb certain %itamins (A328) Too much+ ecess fat stored under the sin (obese) Too little+ %itamins won9t be absorbed, cell membrane won9t be formed normally • • • • •
/* :itamins+ To protect health* Biological catalyst for chemical reaction in the body* " categories+ i) 7at soluble %itamins A,3,2,8 tored in the body fat 4o need to consume e%eryday (stored in the body) • • •
ii) ;ater soluble %itamins C and B (< types) 3issol%ed easily in water, easily lost Cannot be stored in the body, need to be consumed e%eryday* • • •
:itamin A ource+ .il, green leaf, butter, tomatoes, cod li%er, egg* 7unction+ 4ormal growth, healthy eyes & sin* 3eficiency disease+ 4ight blindness* •
:itamin B1 ource+ .il, peas, cereals, green leaf* 7unction+ Growth & de%elopment* 3eficiency disease+ Beriberi (disease affects the ner%ous system)* •
:itamin B" ource+ Peas, yeast, egg, meat* 7unction+ #ealthy sin growth* 3eficiency disease+ in disease, retarded growth* •
:itamin B/ ource+ ;hole cereals, potatoes, tomatoes, meat, fish* 7unction+ #ealthy sin, digesti%e & ner%ous system* 3eficiency disease+ Pellagra (disease affect the sin, alimentary canal & ner%ous system)* •
:itamin C ource+ Tomatoes, green leaf, %egetables, fruits* •
7unction+ #ealthy growth, strong blood %essels* 3eficiency disease+ cur%y (gums easily bleed)* :itamin 3 ource+ unlight, mil, butter* 7unction+ trong bones & teeth* 3eficiency disease+ 6icets ( oft bones & deformed on children)* •
:itamin 2 ource+ :egetables, oils, mil, butter* 7unction+ Protect the cell membrane* 3eficiency disease+ Affect fertility* •
:itamin 8 ource+ Green %egetables, oya bean oils* 7unction+ #elp in clotting the blood* 3eficiency disease+ 2cessi%e bleeding from wound* •
0* .ineral salts+ .a=or trace mineral! re>uired in large amount .inor trace mineral! re>uired in small amount • •
?* @ron ! 7ormation of heamoglobin * Calcium ! trong bones & teeth, muscle contractions, clotting blood <* Phosphorus ! trong bones * Potassium ! Growth & osmotic balance 1* odium ! 'smotic balance, proper functioning of ner%ous system 11* @odine ! Body metabolism, de%elopment of brain 1"* 6oughage fiber #igher water holding capacity #elp peristalsis bowel mo%ement Pre%ent from constipation 5ower the cholesterol 6educe the ris of heart disease • • • • •
1-* ;ater+ .edium for biochemical reactions .edium for transportation of respiratory gases 6egulates body temp* 6emo%es ecretory waste .aintain osmotic pressure Aids peristaltic mo%ement • • • • • •
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#ydrolyse some food substances 3issol%e most chemical substances
SPECIAL DIET
1* Pregnant lady 4eed more nutrient to pro%ide more energy to meet the need of my growing fetus 7olate D brain de%elopment @ron D pre%ent from anemic Calcium ! growth of baby9s bone & teeth •
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"* Baby 4eed mother9s mil to pro%ide me with energy & nutrient* •
-* Children They are acti%e & lo%e to play* They need carbohydrates to gi%e us energy and protein to de%elop new tissue* •
/* :egetarian They need supplement in order to complete their need* •
0* 3iabetic 5ow sugar* •
?* Teenagers Carbohydrates D pro%ides energy (they9re acti%e) Protein D still growing @ron D menstruation (girl) • • •
* Athletes Carbohydrates D they need more energy* •
MALNUTRITION
1* tar%ation D insufficient amount of food "* 2ating disorder+ Anoreia 4er%osa D Girls belie%e themsel%es to be fat (they9re etremlely thin), don9t want to eat* Bulimia D '%erconcern with body weight, eat a lot and then force themsel%es to %omit* •
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-* '%erweight 'besity ! high ris of diabetes,hypertension, heart attac /* '%er consumption of cholesterol & saturated fat+ Can cause arthrosclerosis (build up fatty deposits in the coronary arteries blood %essels* •
0* Constipation+ lac of dietary fiber*
CLASS OF CHEMICALS
Cells need %arious types of organic and inorganic compounds to enable them to carry out their functions, as well as build their cellular components* ;hile organic compounds contain the element carbon, inorganic compounds do not* Below is the classified descriptions of chemical compound* 1* Carbohydrate E tarch made up of long chain of glucose E The ratio of C+#+' in it is 1+"+1 E Cellulose that strengthens the cell walls of plants E .altose can be con%erted into glucose by hydrolysis E @ts glucose molecules can be con%erted into glycogen
"* 5ipid E Cholesterol is an eample of it E 7ats ha%e the triglyceride molecules in them E 7atty acids can be saturated and unsaturated E The hormone testosterone is an eample of it
-* 4ucleic Acid E An eample is the 34A found in the nucleus of a cell E Genetic material that directs protein synthesis E Contain pentose sugars and phosphate groups
/* Protein E Amino acids are its building blocs E 4early all en$ymes are eamples of it E The haemoglobin molecules in the red blood cells E Builds muscles and aids growth
0* ;ater E An inorganic compound with no carbon in it E A polar molecule with two # atoms and one ' atom E A uni%ersal sol%ent E Acts as a medium for reactions in oneFs body
