Hereditary

• Heredity


  The transmission of characters from parent to their offspring's, either by gametes (sperms and oval) by asexual reproductive bodies in reproduction
• Heredity is important to all living organisms as it determines which traits are passed from parents to their offspring's
• Gamete


  A sex-cell, gametes fuse in sexual reproduction forming a zygote
• Zygote


  A diploid cell resulting from the fusion of two gametes; sperm and ovum and give rise to a fertilized egg
• Allele (Allelomorphs)


  One of the contrasting forms of a gene at a particular location called locus on homologous chromosomes
• Chromosome


  A cellular organelle that houses the hereditary unit or the storage unit of genes
• Hybrid


  A plant produced from a cross between two plants with different genetic constituent or a result of mating of parents from two distinct species or character
• Homozygous


  When the members of a gene pair are alike, example RR, AA, bb, rr etc.
• Heterozygous


  When the member of a gene pair is not alike example Rr, Aa, Bb, Yy, etc.
• Homologous chromosome


  Chromosomes that associate in pair during meiosis
• Heterozygous chromosome


  Un-identical pair of chromosomes
• Recessive character


  A gene whose presence is masked by the presence of its dominant allele or a characteristic whose appearance is excluded by the presence of its contrasting character in a hybrid
• Phenotype


  The actual physical observable character appearance of an individual
• Genotype


  The genetic make-up of an individual
• Locus


  The location of a gene on a chromosome
• Filial generation


  The offspring of the parents. First filial generation is denoted by F1, second filial generation by F2, Third by F3, etc. F1 generation give rise to F2 generation
• Heritable characters


  • Albinism
  • Sickle cell trait
  • Blood type
  • Baldness
  • Colour
  • Blindness
  • Colour of eye
  • Skin colour
  • Colour of hair
  • Size of the body
  • Body shape
  • Taste
  • Weight and size of fruits in plants
  • Colour of leaves
  • Flowers and seed type
• Non-heritable characters


  • Piercing of ears or nose
  • Muscles developed by boxers
  • Injury sustained as a result of accident
  • Skill obtained as a result of learning (driving)
• Environment


  The surrounding or society, the fields of an area and even the whole world, foetus it is within mother's womb
• Environment also plays a very important role in determining the behaviour and personality development of an individual
• If a foetus is exposed to pollutants or chemicals in the womb at specific stages in the developmental process, it can alter their deoxyribonucleic acid (DNA), and cause mutations that may not otherwise have occurred
• Sufficient nourishment is also necessary from the mother to the foetus. Otherwise, the child will suffer from malnutrition
• Defects in mother like drug or alcohol addition, smoking, malnutrition, diabetes, endocrinal disturbances, small uterus etc can cause many problems to the child
• Lipoprotein


  Protein molecules that transport fat in the body. They contain cholesterol and triglycerides.
• Lipoproteins


  • Spherical molecules that have a core of cholesteryl esters (a form of cholesterol) and triglycerides
  • On the outside are types of lipid known as phospholipids, free cholesterol, and apolipoproteins or apo
• Main classes of lipoprotein particles

  • Chylomicrons
  • Very low-density lipoproteins (VLDL)
  • Intermediate density lipoproteins (IDL)
  • Low-density lipoproteins (LDL)
  • High-density lipoproteins (HDL)
• Apolipoproteins


  Proteins that help lipoproteins carry out specific functions
• Reverse cholesterol transport


  1. Body removes excess cholesterol from tissues and brings it back to the liver

  2. Gallbladder may remove it from the body, or the body redistributes it
• High triglyceride levels


  Fatty substances can build up in the artery walls, increasing the risk of a stroke or heart attack
• High levels of LDL and VLDL cholesterol


  Linked with the development of atherosclerosis
• Small, dense LDL particles

  Cause more atherosclerosis than larger LDL particles
• High levels of free radicals

  Can lead to damage and inflammation in the body
• HDL


  Helps remove excess cholesterol from the blood and protect against atherosclerosis
• Cell membrane


  • Consists of a lipid bilayer that is semipermeable
  • Regulates the transport of materials entering and exiting the cell
• Plasma membrane


  Thin barrier separating inside of cell (cytoplasm) from outside environment
• Plasma membrane functions


  • Isolate cell's contents from outside environment
  • Regulate exchange of substances between inside and outside of cell
  • Communicate with other cells
• Biological membranes


  • Consist of a double sheet (known as a bilayer) of lipid molecules
  • In addition to lipids, also contain membrane proteins and sugars
• Membrane proteins


  Help to maintain the structural integrity, organization and flow of material through membranes
• Types of lipid found in biological membranes

  • Phospholipids
  • Glycolipids
  • Sterols
• Phospholipids


  Consist of two fatty acid chains linked to glycerol and phosphate