Proteins (Polypeptides)
Proteins are nitrogenous compounds being made up of carbon,
hydrogen, oxygen and nitrogen. Proteins also contain sulphur. In living
systems proteins play an important role in the structural organisation eg.,
cell membrane, hairs, nails and muscles. Many of the proteins serve as
enzymes.
Types of Protein
They are named as functional proteins. The building blocks of proteins are aminoacids. There are approximately twenty different types of amino acids, such as glycine, alanine, serine, valine, leucin, proline etc. The amino acids are classified as essential and non essential amino acids.
Essential amino acids can not be synthesised in our body. Hence they should be made available through food.
Essential Amino Acids
The essential amino acids are arginine, valine, histidine, isoleucine, leucine, lycine, methionine, phenylalanine, threonine and tryptophan. The nonessential amino acids can be synthesized in our body from other compounds. Such amino acids need not be added in the diet.
A protein (or) a polypetide chain is formed of several amino acids
linked with each other by peptide bonds. This linear arrangement is termed
as primary organisation of a protein. However in most of the proteins, the
straight chain structure gets complicated, into secondary, tertiary or quaternary
stages.
These levels are due to several other chemical bonds. The complicated
nature of a particular protein is specifically required for its prescribed function.
The amino-acids sequence and level of ogranisation is determined genetically.
Hence the genome gets its importance due to its capability to produce, specific
types of protein for bringing out genetical characteristics.
The daily requirement of protein, according to the Nutrition experts
committee of ICMR (Indian Council for Medical Research) and WHO (World
Health Organisation) is 1 gm per kg body weight. Reduction in the intake of
protein leads to protein malnutritions, such as marasmus and kwashiorkar.
In marasmas the child loses weight and it also causes severe diarrhoea and
the body muscles get wasted.
It will appear as though the bones are covered by the skin. In kwashiorkar there is a wastage of muscles. Face and feet will have oedema. The belly region will appear enlarged.
Related Topics in Zoology:
Bio Zoology All Important Topics
- Human Physiology Introduction
- Nutrition
- Carbohydrates Poly hydroxyaldehydes (or) ketones
- Proteins (Polypeptides)
- Lipids
- Vitamins – Functions Of Vitamins
- Deficiency of Vitamin
- Minerals – Water – Role of water
- Balanced diet
- Obesity
- Digestive System
- Dental Caries (Tooth decay)
- Root Canal Treatment
- Peptic ulcer
- Hernia and Types
- Appendicitis (Appendix)
- Gall Stones
- Hepatitis
- Fractures – Types of fractures
- Mechanism of fracture
- Dislocation of joints
- Arthiritis
- Rickets and Osteomalacia – Orthopedics
- Muscles
- Mechanism of muscle contraction
- Types of muscle contraction
- Myasthenia Gravis
- Respiration – Process of pulmonary respiration
- Mechanism of Breathing
- Regulation of Respiration
- Pneumonia Tuberculosis Symptoms Treatment
- Bronchitis – Acute bronchitis, Chronic Bronchitis Causes
- Circulatory System – Functioning of Human heart
- Cardiac Cycle
- Coronary blood vessel and its significance
- Myocardial infarction
- Angina pectoris
- Angiogram – Angioplasty
- Atherosclerosis
- Heart block Echo cardiography Heart Valves
- Rheumatic Heart Disease (RHD), ICCU – (Intensive Coronary Care Unit)
- Blood Pressure
- Heart transplantation
- Pulse rate
- Cardio Pulmonary Resuscitation (CPR)
- Blood – Composition of plasma – Blood cells
- Clotting of Blood or Haemostasis
- Thrombosis
- Nervous system Co-ordination systems
- The Brain – Fore Brain, Midbrain, Hindbrain
- Memory
- Sleep – Types of sleep
- Stroke – Brain haemorrhage
- Alzheimer – Meningitis (Brain fever)
- Conditioned reflex
- Electroencephalography EEG
- Right and Left brain concept
- Spinal cord functioning
- Chemical co-ordination – Functions of Endocrine glands
- Hypothalamus
- Pituitary gland – hormone
- Hormones of Neurohypophysis – vasopressin
- Thyroid gland
- Parathyroid Gland
- Pancreas
- Adrenal gland
- Gonads
- Receptor Organs – Eye
- Photochemistry of Retinal visual Pigments
- Errors of refraction
- Optometry – Retinopathy
- Cataract – Lens Replacement – Glaucoma – Nyctalopia
- Eye Infections and Eye Care
- Ear
- Mechanism of hearing
- Defects of the ear
- Hearing Aid – Noise pollution
- Skin and functions of skin
- Melanin functions
- Effects of solar radiation / UV radiation – Skin grafting
- Dermatitis
- Tongue – Mechanism of Stimulation
- Excretion Ureotelism Nephron
- Mechanism of urine formation
- Renal Failure, Dialysis, Kidney Machines
- Kidney stone – Kidney transplantation
- Diabetes mellitus
- Functioning of male reproductive system
- Functioning of female reproductive system
- Ovulation and fate of the ovum – Menstrual cycle
- Fertilization
- Birth control