Prelims 1

• Biochemistry


  Study of the chemical processes within and relating to a living organism
• Biomolecules


  Principal classes are: Carbohydrates, Proteins, Lipids, Nucleic Acid
• These molecules make up all living organism (Carbs, CHON, etc.)
• Biochemistry


  The chemistry of the living organisms
• Functions of biomolecules

  • Carbohydrates: Energy source of our body
  • Proteins: Structural functions, Promote chemical reactions (enzymes)
  • Lipids: Long term energy storage in the body and structure for cell membrane
  • Nucleic Acid: Stores genetic materials, Energy for the cell (ATP)
• The biomolecules in our body doesn't only work its functions. It can also serve as an indicator or marker to tell us that there is something wrong or there is an abnormality happening inside our body.
• Biomolecules as indicators


  • Lipids: Lipid profile test can detect atherosclerosis
  • Nucleic Acid: Used in diagnosing diseases using PCR testing
  • Proteins: Hemoglobin can indicate anemia
  • Carbohydrates: Blood sugar testing can detect diabetes mellitus
• Biochemistry is faced in our daily lives
• Physicians face biochemistry every day
• All diseases are associated with abnormalities in biochemistry because chemical functions occur inside our body
• Biomolecules can serve as analyte to detect abnormalities in our body
• Biochemistry is not only applicable in human beings it can also be applied to the technology or to test the microorganisms such as bacteria
• Carbohydrates


  Most common organic molecule, Function: Primary energy source our body needs, Elements present: Carbon, Hydrogen, and Oxygen (1:2:1)
• Carbohydrate monomers and polymers

  • Monosaccharides (Glucose is the most common)
  • Polysaccharides (starch, glycogen, cellulose, chitin)
• Examples of carbohydrates


  • chocolate, bread, pasta, fruits, vegetables
• All carbohydrates are from PLANTS
• Types of sugars

  • Monosaccharide (one carbohydrate content, e.g. glucose, fructose)
  • Disaccharide (2 monosaccharides, e.g. maltose, sucrose)
  • Polysaccharide (3+ monosaccharides, e.g. starch, glycogen, cellulose, chitin)
• Lipids


  Function: Storage of energy, insulates the body, and makes up the cell membrane, Elements: C-H-O, Monomer: Glycerol and 3 Fatty Acids, Polymer: Phospholipids, triglyceride
• Examples of lipids


  • steroids, cholesterol, fats, oils, nuts, waxes and make up part of the cell membrane
• Not all lipids are harmful in our body, there are some lipids that are good
• Lipids


  They are hydrophobic (water-fearing) and do not dissolve in water
• Types of lipids

  • Saturated (Solid at room temperature, Mainly animal fats)
  • Unsaturated (Liquid at room temperature, Mainly plant-based fats as well as oily fish)
• Proteins


  Transport molecules in and out of the cell, Control the speed of chemical reactions, Used for growth and repair, Elements: C-H-O-N, Monomer: amino acids (20 different amino acids), Polymer: proteins
• Examples of proteins

  • hemoglobin in red blood cells, albumin in eggs, enzymes that control reactions in the body and antibodies
• Proteins are found in fish, eggs, meat
• Nucleic Acids


  Function: provide our genetic information, Holds the instructions to make proteins, Elements: C-H-O-N-P, Monomer: nucleotides, Polymer: DNA, RNA and ATP
• Components of a nucleotide

  • Sugar
  • Phosphate
  • Nitrogen base: A [Adenine], T [Thymine], G [Guanine], C [Cytosine] or U [Uracil]
• DNA is composed of A-T-G-C, RNA is composed of A-T-G-U, ATP is a nucleic acid compound composed of 3 phosphate groups with ribose sugar and adenine nitrogenous base
• Cell

  Biochemistry explores molecular mechanisms of normal cellular processes as well as diseases, All higher living organisms including humans are made up of cells, Cell is the smallest part of an organism, Basic structural and functional unit of all living organisms
• Characteristic functions of the cell

  • Cell Metabolism and Energy Use
  • Synthesis of Molecules
  • Communication
  • Reproduction and Inheritance
• Two major classes of cells


  • Prokaryotes
  • Eukaryotes
• Three parts of a cell


  • Plasma Membrane
  • Nucleus
  • Cytoplasm
• History of cell

  Robert Hooke was the first person to use the term "cell", Matthias Schleiden and Theodor Schwann concluded that all plant and animal tissues were composed of cells, Rudolf Virchow proposed the theory of biogenesis where cells only arise from pre-existing cells
• Cell theory


  A cell is living organisms' basic structural and functional unit, The activity of an organism depends on the collective activities of its cells, The activities of cells are dictated by their structure (anatomy), which determines function (physiology)
• Differences between eukaryotic and prokaryotic cells

  • DNA is found in the nucleus of the cell (eukaryotes) vs DNA is not enclosed within the membrane (prokaryotes)
  • Contain membrane-bound organelles (eukaryotes) vs Lack membrane-enclosed organelles (prokaryotes)
  • Cell division involve mitosis (eukaryotes) vs Usually divide by binary fission (prokaryotes)
• Molecular composition of cell

  Water accounts for about 70-75% of the weight, Organic compounds accounts for 25-30% (nucleic acids, proteins, polysaccharides, lipids), Proteins account 10-20% of the weight, Inorganic compounds account for the rest
• Cytoplasm

  Structure: Fluid filled interior cell "free floating", Organelles are membrane-bound structures that carry out specific cell metabolic activities, Cytosol provides support for organelles and serves as the viscous fluid medium
• Nucleus


  Most prominent organelle, Contains the DNA, Enclosed within a double membrane called a nuclear envelope, Contains nucleolus which consists of RNA and proteins for ribosomal unit assembly, Nucleoplasm surrounds the chromatin and the nucleoli
• Plasma Membrane

  Structure: Phospholipid bilayer containing cholesterol and proteins and some carbohydrates, Acts as a physical barrier to enclose cell contents, Regulates material movement into and out of the cell, Functions in cell signaling
• DNA


  The chemical basis of our genes that governs all the functions of the cell