Biology – Nutrition Sample Essay

Type of Nutrition
* Nutrition – procedure by which organisms obtain energy and foods from nutrient. for growing. care and fix of damaged tissues. * Nutrients – the of import substances which are required for nutriment of an being. * Populating beings are divided into two groups ( based on the nutritionary wonts ) : autophyte and heterotrophs.

( I ) Autophyte
* Autotrophs – organisms that are able to synthesize complex organic compounds from natural. simple inorganic substances ( H2O and air ) by utilizing visible radiation or chemical energy. These beings manufacture their ain nutrient by photosynthesis or chemosynthesis. * Photoautotrophs – chlorophyll incorporating beings that utilise solar energy for constructing organic substance. * Photoautotropic nutrition = holophytic nutrition.

* Chemoautotrophs – organisms synthesize organic substances by using chemical energy. Autotrophs Example
Photoautotroph Trees
Chemoautotroph Bacteria

( two ) Heterotroph
* Heterotrophs – organisms that are non able to synthesize their ain foods but they obtain the foods from other beings. * Holozoic nutrition – beings feed by consuming solid organic affair that digested and absorbed into the organic structures. * Saprophytism – organisms feed on dead and disintegrating organic affair. * Parasitism – organisms obtains foods ( absorbs readily digested nutrient ) by populating on / in the organic structure of another life being ( the host ) Heterotrophs Example

Saprophyte Fungi
Holozoic nutrition Carnivores
Carnivorous workss ( Holozoic nutrition ) Venus traps and hurler workss
Parasites Lice and fleas


Human Teeth
Balanced Diet
* Diet – the nutrient and imbibe that we consume.
* Balanced diet – diet contains the right proportions of all the different categories of nutrients for the demand of organic structure. * Metabolisms – the amount of all biochemical reactions that occur in the cells of life beings. * Metabolic rate – a step of the energy demands of the life organic structure over a specified period of clip. Unit – kilojoule ( kJ ) * Energy value / calorific value of nutrient – the measure of heat produced when one gm of nutrient is wholly oxidised. Unit – Joules per gm ( J g-1 ) or Calories. * Energy value = ( Mass of H2O ten Increase in temperature x 4. 2 ) / Mass of nutrient * Energy value = ( g ) ( ?C ) ( J g-1?C-1 ) / ( g ) = J g-1


Seven Important Classes of Food
1. Carbohydrates ( supply energy )
2. Proteins ( Build new tissues / of import in growing and mending damaged tissues ) 3. Fats ( supply energy / storage of excess nutrients )
4. Water ( act as medium for biochemical reaction / transit of substances ) 5. Vitamins ( prevent diseases / efficient metamorphosis / of import for normal growing ) 6. Minerals ( of import for normal growing and development of dentitions. castanetss and musculuss ) 7. Roughage / Dietary fibre ( prevent irregularity / stimulate vermiculation )


Nutrition Tag
Factors Affecting Daily Energy Requirement
Balance diet is indispensable for healthy growing and development of the organic structure. 1. Age – kids and adolescents need more energy due to their high metabolic rate. 2. Sexual activity – male grownup needs more energy due to in males have high metabolic rate. 3. Pregnancy and lactation – pregnant adult females need more energy due to back up the turning fetuss and produce milk for their babes. 4. Occupation – an active individual requires high energy due to the individual does a batch of heavy work. 5. Size or personify weight – a individual smaller in size has a larger surface country per unit volume. Therefore. the rate of heat loss is high. 6. Climate – people populating in cold states need more energy to keep organic structure temperature. 7. Geneticss – genetic sciences temperament in certain individual may make up one’s mind different metabolic rate. 8. Health – In sufficient secernment of tetraiodothyronine endocrine may do lower in metabolic rate. 9. Lifestyle – An active individual requires higher energy than a inactive individual

Energy Content of Food
* Bomb calorimeter – used to cipher the energy value of assorted types of nutrient samples. * One Calorie ( cal ) = 4. 2 Js ( J )
* Energy value of nutrient ( kJ g-1 ) = ( 4. 2 ten mass of H2O ten addition in temperature ) ( mass of nutrient sample x 1000 ) * specific heat capacity of H2O. C = 4. 2 J g-1 ?C-1 ; mass of H2O in g ; temperature in ?C and mass of nutrient sample in g.

Classs of Food Foods
Classs of Food Foods
Test Reagent Observation Conclusion
Benedict’s trial Food sample + Benedict’s solution ( Place in boiling H2O bath ) The solution turns from blue to green / yellow / brick-red precipitate formed ( depend on sugar concentration ) . Food sample contains cut downing sugar Benedict’s trial Food sample + Benedict’s solution + Dilute hydrochloric acid ( Place in boiling H2O bath ) + neutralise by Na H carbonate pulverization The solution turns from blue to green / yellow / brick-red precipitate formed ( depend on sugar concentration ) . Food sample contains non-reducing sugar Iodine / Starch trial Food sample + Iodine solution The solution turns frombrownish-yellow to blue-black. Food sample contains starch Emulsion trial Food sample + ethyl alcohol


The fat droplets formed on the surface and the solution become cloudy. Food sample contains oil ( lipid ) Sudan III trial Food sample + Sudan III stain A red-stained oil bed separates out and drift on the H2O surface Food sample contains oil ( lipoid ) Fat trial Food sample + filter paper A translucent grade formed Food sample contains oil ( lipid ) Millon’s trial Food sample + Millon’s reagent + 1 % Na nitrite ( Place in boiling H2O bath ) The solution turns brick-redprecipitate. Food sample contains protein Biuret trial Food sample + 20 % Na hydroxide solution and 1 % Cu ( II ) sulfate solution The solution turns from blueto violet coloring material. Food sample contains protein

Vitamin Cod oil
Vitamins
* It is a group of complex organic compounds that are needed in little measures by populating beings because vitamins can be reused in organic structure metamorphosiss. * Vitamins do non supply energy to personify metamorphosis and vitamins are non-protein organic compounds. * Populating beings can non synthesize vitamins.

* Vitamins can be merely obtained from diet.
* It is indispensable to care of good wellness. normal growing and efficient metamorphosis. * There are two classs in vitamins: fat-soluble vitamins and water-soluble vitamins.

Fat-soluble Vitamins
Types of Vitamins Sources Functions Effect of lack A ( vitamin A1 ) Milk. carrots. tomatoes. eggs. fish oil. green veggies. butter – Builds ocular pigments on retina for dark vision- Immunity- Growth of epithelial cells- Antioxidant- Build organic structure opposition to diseases – Night blindness- Xerophthalmia ( cornea becomes dry ) – Lepidote tegument D ( vitamin D ) Formed ( tegument ) during the presence of sunshine. fish liver oil. egg yolk. cheese – Enhances soaking up of Ca and phosphorus- Build strong castanetss and healthy dentitions – Rickets ( weak castanetss ) – Osteomalacia ( softening of castanetss ) E ( vitamin E ) Palm oil. cereals. nuts. green veggies. olive oil. milk- – Preserves healthy muscular system. blood circulatory ( ruddy blood cells ) and nervous system- Antioxidant- Maintain healthy map of the reproduction system – Premature aging- Low fertility- Slow lesion mending K ( vitamin K1 ) Green veggie. totatoes – Helps in blood curdling – Detective blood clotting- Anaemia

Cod fish oil
Water-soluble Vitamins
Types of Vitamins Sources Functions Effect of lack B1 ( vitamin B1 ) Milk. legumens. wheatgerm. yeast infusion. nuts. whole grains – Precursor of a coenzyme – Coenzyme for saccharides metabolisme – Beri-beri ( musculus failing. nerve upset ) – Fatigue B2 ( vitamin B2 ) Milk. wheatgerm. liver. eggs – Component of coenzyme – Healthy nervous system – Sore eyes- Skin lesions at the corner of oral cavity. nose and ears- Inflammation of lingua and lips B3 ( nicotinic acid ) Liver. rice. leguminous plants. fish. yeast extract – Component of coenzyme- Healthy nervous system. tegument and bowels – Pellagra ( tegument and GI lesions ) B5 ( pantothenic acid ) Fish. egg yolk. liver. meat – Component of coenzyme for saccharides. protein and fatty acids metamorphosis – Muscle cramps- Fatigue- Grey hair- Low unsusceptibility B6 ( vitamin B6 ) Fish. liver. milk. murphies – Coenzyme in aminic acerb metabolism- For ruddy blood cell formation – Kidney stone- Muscular twitching- Diarrhea B9 ( folic acid )

Green veggies – For DNA and RNA- For ruddy blood cells formation- Regulating the map of Fe – Miscarriage birth- Cleft lips- Limb defects of babes B12 ( vitamin B12 ) Cheese. milk. egg. meat – Coenzyme in nucleic acerb metamorphosis – For ruddy blood cells formation – Baneful anaemia- Neurological upsets H ( vitamin H ) Legumes. veggies – Coenzyme in the synthesis of fat. animal starch and amino acid – Nausea- Fatigue- Muscular strivings C ( ascorbic acid ) Orange. tomatoes. Brassica oleracea italica. cauliflower – Fats and protein metamorphosis – Energy production – Scurvy ( shed blooding gums and bruised tegument )