Nutrition, Health and Diseases
Category : UPSC
NUTRITION, HEALTH AND DISEASES
NUTRITION
Nutrition is the process of intake and utilisation of nutrients/ food, by an organisms to get energy which is further used in various life processes. The substance that is needed to keep them living is called nutrient.
Nutrients are organic and inorganic substances which the organism obtains from its surroundings and uses it as a source of energy or for biosynthesis of its body constituents.
Organic nutrients - Carbohydrates, Proteins, Fats Inorganic nutrients - Water, Carbon dioxide, Minerals (Iron, copper, zinc, etc.)
NUTRITION IN PLANTS
Various organisms live in different environmental conditions and they have different methods of obtaining nutrients from the environment. The method of obtaining food by the organism is called mode of nutrition. Depending on the mode of nutrition, all organisms can be classified into two major groups - Autotrophic and Heterotrophic.
|
Nutrition in Plants |
|
|||
|
\[\downarrow \] |
|
|||
|
\[\downarrow \] \[\downarrow \] |
|
|||
Autotrophic |
Heterotrophic |
||||
Organisms which can make their own organic food from inorganic raw materials (carbon dioxide and water) and remain independent of obtaining external source of organic compound are called Autotrophs. All green plants are autotrophs. |
Plants are generally autotrophic but there some plants which are unable to manufacture their food, due to lack of chlorophyll like parasitic plants saprophytic and insectivorous plants or symbionts |
||||
Role of Micro and Macro Elements and Their Deficiency Symptoms
S. no. |
Name of element (location) |
Functions |
Deficiency symptoms |
1. |
Nitrogen \[(N{{O}_{2}}^{-},N{{O}_{3}}^{-}or\,\,N{{H}_{4}}^{+})\] |
Major constituent of proteins, nucleic acids, vitamins and minerals. |
Chlorosis of leaves, stunting of plants, dormancy of lateral buds, inhibition of cell division etc. |
2. |
Phosphorous \[({{H}_{2}}P{{O}_{4}}^{-},or\,\,HP{{O}_{4}}^{2-})\] |
Constituent of cell membrane, nucleic acids, nucleotides and some proteins. |
Delay in seed germination, reduced growth, purple or red spots on leaves etc. |
3. |
Potassium \[({{K}^{+}})\] |
Determine cation- anion balance in cell. Involved in protein synthesis, closing & opening of stomata. |
Scorched leaf tips, shorter intemodes, chlorosis in interveinal, loss of apical dominance, loss of cambial activity. |
4. |
Calcium \[(C{{a}^{2+}})\] |
Activate certain enzymes and regulates metabolic activities. Used in synthesis of cell wall (middle |
Stunted growth, necrosis (death of tissue) of meristematic regions, chlorosis along the margins of young leaves, wither tip disease, premature flower abscission, blossoms end rots of tomato. |
5. |
Magnesium (divalent \[M{{g}^{2+}}\]) |
Activate enzymes in respiration, photo -synthesis, DNA and RNA synthesis. |
Chlorosis between leaf veins, necrosis on older leaves. Premature leaf abscission, reduced growth. |
6. |
Sulphur \[(S{{O}_{4}}^{2-})\] |
Constituent of amino acids like cystine and methionine and Main constituent of several coenzymes, vitamins (thymine, Co-A and ferredoxin, biotin) |
Chlorosis of younger leaves, stunted growth, anthocyanin accumulation, leaf curl, less juice content in citrus, yellow disease of tea, marsh spots (peas)c. |
7. |
Iron \[(F{{e}^{3+}})\] |
Constituent of ferredoxin and cytochromes. Involves in electron transfer. Activates catalase and Helps in formation of chlorophyll. |
Chlorosis-initiates in intravenous regions and then in the complete leaf, growth reduced, inhibition of chloroplast formation. |
PHOTOSYNTHESIS
Green plants are autotrophic in the sense that they synthesize their own organic food from inorganic raw materials. This is done by the process of photosynthesis.
\[_{carbon\,\,dioxide}^{6C{{O}_{2}}}+_{water}^{12{{H}_{2}}O}\xrightarrow[Chlorophyll]{Light}_{Glu\cos e}^{{{C}_{6}}{{H}_{12}}{{O}_{6}}}+_{water}^{6{{H}_{2}}O}+_{oxygen}^{6{{O}_{2}}}\]
PHOTOSYNTHESIS IN HIGHER PLANTS
Photosynthetic Pigments
Chlorophyll b
Chlorophyll c
Carotenes - \[{{C}_{40}}{{H}_{56}}\] and Xanthophylls - \[{{C}_{40}}{{H}_{56}}{{O}_{2}}\].
MECHANISM OF PHOTOSYNTHESIS
(i) light Reaction
(ii) Dark Reaction
Light reaction
It occurs in grana fraction of chloroplast and in this reaction are included those activities, which are dependent on light. Assimilatory powers (ATP and\[NADP{{H}_{2}}\]) are mainly produced in this light reaction.
Non Cyclic Photophosphorylation
Cyclic Photophosphorylation
In this light reaction of photosynthesis, the formation of ATP from ADP and\[{{H}_{3}}P{{O}_{4}}\]in the presence of light & chlorophyll a during the cyclic transfer of electrons is called cyclic photophosphorylation. The system is found dominantly in bacteria. It involves only PS I. Flow of electron is cyclic. If NADP is not available then this process will occur. When the photons activate PS I, a pair of electrons are raised to a higher energy level. They are captured by primary acceptor which passes them on to ferredoxin, plastoquinone, cytochrome complex, plastocyanin and finally back to reaction centre of PS I i.e., \[{{P}_{700}}\]. At each step of electron transfer, the electrons lose potential energy. Their trip down hill is caused by the transport chain to pump H4' across the thylakoid membrane.
Dark Reaction
Dark reaction is a thermochemical reaction. It takes place in the stroma of the chloroplast.
It is also called \[C{{O}_{2}}\]fixation or carbon assimilation.
The dark reaction involves thermochemical reduction of \[C{{O}_{2}}\]to form carbohydrates. This was first established by Blackmail (1905), hence it is also called Blackmail reaction.
There are two main pathways for the biosynthetic or dark phase - Calvin cycle (\[{{C}_{3}}\]) and \[{{C}_{4}}\] (dicarboxylic acid) cycle.
Calvin Cycle-(\[{{C}_{3}}\] Cycle)
Carbon assimilation in \[{{C}_{3}}\] plants were explained by Melvin Calvin
\[l\]This is known as \[{{C}_{3}}\] cycle because \[C{{O}_{2}}\]reduction is cyclic process and first stable product in this cycle is a 3-C compound (i.e., 3-Phosphoglyceric acid or -PGA. Calvin cycle occurs in all photosynthetic plants whether they have \[{{C}_{3}}\] or \[{{C}_{4}}\] pathway.
\[{{C}_{4}}\] Cycle
Table Difference between \[{{C}_{3}}\] and \[{{C}_{4}}\] Plants
|
\[{{C}_{3}}\]Plants |
\[{{C}_{4}}\]Plants |
1. |
Photosynthesis occurs in mesophyll cells. |
Photosynthesis occurs in mesophyll and bundle sheath cells. |
2. |
Kranz anatomy is absent. |
Kranz anatomy is present. |
3. |
RuBP is the primary carbon dioxide acceptor. |
PEP is the primary carbon dioxide acceptor. |
4. |
3-phosphoglyceric acid (3-PGA), a 3C-compound is the first stable product. |
Oxaloacetic acid, a 4C-compound is the first stable product of photosynthesis. |
5. |
Chloroplast are of only one type, i.e., granal. |
Chloroplasts are dimorphic, i.e., granal in the mesophyll cells and agranal in the bundle sheath cells. |
NUTRITION IN ANIMALS
It is a biochemical process in which animals derives nutrients in the form of organic and inorganic substances for the proper maintenance and for all metabolic and catabolic activities occurs in the body.
Nutrition
Nutrition is divided into three types:
Holozoic
(i) Herbivores, (ii) Carnivores, (iii) Omnivores
Saprazoic
Ex-insects in drainage, on pickles, etc.
Parasitic
Macronutrients can be Summarized in the Flow Chart give Below:
VITAMINS
Vitamins are organic compounds essential in trace amounts to the health of animals. Vitamins can be water soluble or fat soluble.
Fat Soluble Vitamins: These vitamins are stored in the liver in fat droplets.
Name |
Source |
Functions |
Deficiency symptoms |
Vitamin A (Retinol) |
Carrot, tomato, papaya, mango, milk, eggs, cod-liver oil |
Essential role for vision, growth, differentiation of epithelial tissue. |
Night blindness, xerophthalmia poor growth, rough and dry skin. |
Vitamin D It exists in two Forms \[{{D}_{2}}\] (Ergocalciferol) and\[{{D}_{3}}\] (cholecalciferol). |
Cod liver oil. Skin can synthesize Vitamin D in the presence of sunlight. |
It promotes growth of bones and teeth |
Rickets in children and osteomalacia in adult. |
Vitamin E (Tocopherol) |
Wheat germ, green leafy vegetables. Fats of vegetable origin |
Acts as good antioxidant, essential for normal functioning of reproductive organs |
Reproductive failure, muscular dystrophy increased haemolysis leading to macrocytic anaemia |
Vitamin K There are three deri vatives of vitamin K. |
Leafy vegetables, wheat germ, Vitamin K is synthesized by bacteria of large intestine. |
I helps in blood clotting, prevention of excessive bleeding. |
Faculty blood clotting. |
Water soluble Vitamins Water soluble vitamins travel freely through the body, and excess amounts usually are excreted by the kidneys. The body needs water soluble vitamins in frequent small doses. Important water soluble vitamins are summorized below in the table. |
|||
B- Complex Vitamin \[{{B}_{1}}\] (Thiamine) |
Whole gain wheat germ, legumes, nuts, fish. |
It acts as thiamine pyrophosphate (TPP) in TCA cycle (Kerbs Cycle) |
Beri beri disease (B1) deficiency in alcoholics causes Wernicke?s syndrome and Korsakoff?s syndrome |
Vitamin \[{{B}_{1}}\] (Riboflavin) |
Milk, chees, meats, eggs, legumes, wheat germ mushrooms, green leafy |
It helps in RBCs production. It acts as FMN and FAD. FMN acts in ETC. however FAD acts in |
Cheilosis |
Vitamin C (Ascorbic acid) |
Cirtrus fruits amla, guava, tomato. |
Essential for the formation of RBCs and the production of antibodies. |
Its deficiency causes Scurvy |
HEALTH AND DISEASE
Anything that disturbs the proper functioning of cells, tissues and organs will result in the lack of proper activity of the body or unhealthy body. Thus, health is considered to be the state of perfect functioning of body and mind, unhindered by diseases. A good health is a healthy body with a healthy mind and healthy attitude.
Health is a state of complete physical, mental and social well-being, and not merely an absence of disease or infirmity (W.H O -1948). Any change from the normal state that causes discomfort or disability or impairs the health is called as disease.
Communicable Disease
Table: Bacterial Diseases in Human
S. No. |
Disease |
Pathogen |
Main Symptoms |
1. |
Cholera (Haiza) |
Comma shaped -Vibrio comma (V. cholerae) |
Severe diarrhoea and vomiting |
2. |
Pneumonia |
Diplococcus or Streptococcus pneumoniae |
Sudden chill, chest pain, difficulty in breathing |
3. |
Typhoid |
Rod like motile Salmonella typhi |
Constant fever . |
4. |
Tubercuslosis |
Mycobacterium tuberculosis (rod shaped).. |
Cough, bloody sputum, chest pain, loss of weight |
Viral Diseases
Table: Viral Diseases in Humans
S. No. |
Disease |
Pathogen |
Main Symptoms |
1. |
Influenza (Flu) |
Myxovirus Influenzae |
Nasal discharge, sneezing, coughing, fever, body ache |
2. |
Chicken pox |
Varicella zoster (DNA vims) |
Skin sores that open & emit fluid |
3. |
Poliomyelitis (polio) (Highly infectious disease of infants and children?s) |
Polio virus |
Inflammation of nervous system, muscle shrinkage, limb paralysis |
4. |
Dengue |
Arbo virus (RNA) |
Mild conjunctivitis, high fever, backache, nausea vomiting etc. |
5. |
Hepatitis (Epidemic jaundice) |
Infections & serum hepatitis viruses (A, B, C, D & E) |
Jaundice due to damaged liver cells |
|
- Hepatitis A (also called catarrhal jaundice) |
A virus |
Hepatic anorexia resulting in liver damage |
|
- Hepatitis B |
B virus |
Swelling of liver cells |
Protozoan disease
|
|||
|
Disease |
Causative agent |
Symptom |
1. |
Malaria |
Plasmodium (female anopheles as vector) |
It results in anaemia, toxaenia and splenomegaly. Antimalarial drugs are quinine, chloroquine etc. Dalaprim drug kills the parasitic stages present in both liver cells and RBC?s of blood. |
2. |
Amoebiasis |
Entamoeba histolytica |
It is characterized by abdominal pain alternating diarrhoea and constipation etc. Entamoeba secretes cytolysin that erodes the mucous membrane of intestine. |
Table: Sexually Transmitted Diseases (STD) in Human
S. No. |
Disease |
Causative organism |
Symptoms-Treatment |
1. |
AIDS |
Retrovirus - HIV |
Enlarged lymph nodes, long fever, weight loss - Nil |
2. |
Genital Herpes |
Herpes simplex virus |
Painful ulcer on genitals - Nil |
3. |
Genital warts |
Human papilloma virus (HPVs) |
Tumor of the vulva, vagina, anus and penis - Nil |
4. |
Syphilis |
Treponema pallidum |
Cancer and skin eruption - Benzene and Penicillin |
Non-Communicable Diseases
The main non-communicable diseases are diabetes, inflammatory diseases of joints such as arthritis, gout, cardiovascular diseases and cancer.
Diabetes Mellitus
Diabetes is characterized by chronic hyper glycemia which is excessive concentration of glucose in the blood. It primarily a result of relative or complete lack of insulin secretion by the \[\beta \]cells of islets of Langerhans in pancreas.
Arthritis
Arthritis is any inflammatory condition of the joints characterized by pain and swelling.
|
Arthritis |
|
||||
|
\[\downarrow \] |
|
||||
|
\[\downarrow \] \[\downarrow \] \[\downarrow \] |
|
||||
Rheumatoid arthritis |
Osteoarthritis |
Gout |
||||
It is characterized by inflammation of the synovial membrane. It is kind of rheumatoid arthritis that occurs in younger people is Still?s disease, and usually starts in the small joints in the hand and progress to other body joints. |
It is a common disease among the elderly persons resulting from erosion of articular cartilage. In osteoarthritis, the secretion of lubricating synovial fluid between the bones at the joint stops. |
Gout results from accumulation of uric acid crystals in the synovial joints. It is a disease associated with an inborn error of uric acid metabolism that increases production or interferes with the excretion of uric acid. |
||||
Cardiovascular Diseases
CANCER
Cancer is an abnormal and uncontrolled division of cells, known as cancer cells that invade and destroy the surrounding tissues. Neoplasm (called tumor) is a new abnormal tissue which is capable of continued growth. Tumors may be benign and malignant.
Tumor |
|
Benign |
Melignant |
Benign tumor is a large localized mass of abnormal tissue enclosed in connective tissue which does not invade adjacent tissue. |
Malignant tumor is not encapsulated and is capable of invading adjacent tissues and distant sites. |
Symptoms of Cancer
Causes of Cancer
Depending on their mode action, carcinogens fall into the following main categories:
(i) Agents that can cause alterations in the genetic material (DNA), resulting in oncogenic transformation.
(ii) Agents that promote the proliferation of cells, which have already undergone genetic alterations responsible for oncogenic transformation. These agents are called tumour promoter, e.g. some growth factors and hormone.
(iii) Cancer causing DNA and RNA viruses (tumour viruses) have been shown to be associated with oncogenic transformation.
Treatment
AIDS
Investigation
Treatment
- AZT (Azidothymidine) or Zidowdine
- DDI (Dideoxyinosine)
- Foscamet
These drugs inhibit the enzyme of HIV
IMMUNE SYSTEM
Acquired Immunity
|
Aquired immunity |
|
|||
|
\[\downarrow \] |
|
|||
|
\[\downarrow \] \[\downarrow \] |
|
|||
Active acquired immunity |
Passive aquired immunity |
||||
Resistance developed by an individual as a result of an antigenic stimulus. |
It is received passively by host without participation or contribution from host s immune system. Immunological memory is absent here and the readymade antibodies are given in immuno suppressive individual. |
||||
Antibodies: These are complex glycoproteins made up of polypeptide chains.
S. No. |
Group of Antibodies |
Main Characters and occurrence |
Functions |
1. |
IgA |
The primary antibodies present in colostrum, present in saliva, mucus and other secretions. |
Protection of mucous membranes and outer surface of body and protection from inhaled ingested pathogens. |
2. |
IgD |
Present in trace amount on the surface of lymphocytes in blood. |
Activation of B-lymphocytes and development and maturation of immune reactions. |
3. |
IgE |
Present in very small quantities, show specific linkage with mast cells and basophils. |
Stimulation of mast cells. Related to allergic reactions and protection from parasites. |
4. |
IgG |
Most abundantly found antibodies, main immunoglobulin of blood and interstitial fluid which has capacity to pass through placenta. |
Stimulate the complementary system, provide immune power to human embryo and specific linkage with phagocytic cells for phagocytosis. |
5. |
IgM |
Oldest and first antibody generated in response to antigens, present in blood plasma (80% ) and interstitial fluids and largest sized immunoglobulin with pentameric form, M.W. |
First line of defense against bacteria, perfection of agglutination, related to complement system. |
Table: Some Important Vaccines
S. No. |
Name of Vaccine |
Used for treatment of |
1. |
B.C.G. |
Tuberculosis |
2. |
Cholera vaccine |
Cholera |
3. |
Oral Polio Vaccine (OPV) |
Polio, 1st dose given when child is 3 months old. Booster dose is given after 1 year |
4. |
Tetanus toxoid (TT) |
Tetanus |
You need to login to perform this action.
You will be redirected in
3 sec