• Share
  • Email
  • Embed
  • Like
  • Save
  • Private Content
Biochemistry
 

Biochemistry

on

  • 6,147 views

 

Statistics

Views

Total Views
6,147
Views on SlideShare
5,975
Embed Views
172

Actions

Likes
31
Downloads
0
Comments
6

12 Embeds 172

http://nclc.blackboard.com 79
https://clev.blackboard.com 29
http://commackibbio15.blogspot.com 25
http://pinterest.com 15
https://nclc.blackboard.com 11
http://www.slideshare.net 4
http://cursos.itesm.mx 3
https://smu.blackboard.com 2
https://thesys.blackboard.com 1
http://bbpprd.lipscomb.edu 1
https://bblearn-preview1.blackboard.com 1
https://explore.vccs.edu 1
More...

Accessibility

Categories

Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel

16 of 6 previous next Post a comment

  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

    Biochemistry Biochemistry Presentation Transcript

    • Chemistry Of Life
    • Atoms
      • Atoms are the smallest forms of matter that retain the chemical characteristics of a given element
      • Atoms have a nucleus , which:
        • Contains protons (p)
        • May contain neutrons (n)
      • Clouds of electrons (e) surround the nucleus
    • Protons, Electrons, & Neutrons
      • Protons have +1 charge and have a mass of 1 atomic unit (AU)
      • Neutrons have no charge but have a mass of 1.005 AU
      • Electrons have a -1 charge and a mass of 1/1800 AU
    • The Periodic Table
    • Atomic Number & Atomic Weight
      • The number of protons is called the atomic number
      • The atomic number defines the element – if the number of protons changes, the element changes
      • The number of protons + the number of neutrons = the atomic weight
      • In an uncharged atom, the number of protons equals the number of electrons
    • Ions
      • The net charge on an atom is usually zero, because the number of electrons is usually equal to the number of protons.
      • If the number of electrons does not equal the number of protons, the atom is called an ion .
      • Ions have a net charge.
    • Elements
      • Elements are substances that cannot be broken down into simpler substances
      • account for >
      • Other elements are important too but are present in small quantities
      • • Nitrogen which is found in protein (CHON)
      • • Calcium which is found in bones / teeth
      • • Iron which is to be found in hemoglobin (animal)
      • • Sodium which is needed for a nerve impulse
      • • Phosphorus found in cell membrane structures
      Most common chemical elements ( 98 % of mass of living organisms comes from O, C, H, N, Ca, and P ): • Carbon (C) • Oxygen (O) • Hydrogen (H)
    •  
    •  
    •  
    •  
    •  
    • Examples of Fe
    •  
    •  
    • Black Smoker Hydrothermal vents
    •  
    • Bonds
      • Atoms stick together by linkages we call bonds .
      • Bonds come about because of reorganization of electron structure in the valence shells of the constituent atoms.
      • All biological reactions involve some sort of reorganization of bonds.
      • Bond reorganization (breakage or building of bonds) results in the uptake or release of energy.
      • Bond energy is the energy needed to break a given bond.
    • 1. Covalent Bonds
      • In covalent bonds , two electrons are shared per bond
      • More than one bond can occur between two atoms
    • 2. Ionic Bonds
      • In ionic bonds, electrons are donated by one atom to another
      • An electronegative atom steals an electron from another atom to fill its valence shell
      • That is, one or more electrons LEAVE one atomic center to ‘live’ with another
    •  
    • Ionic Bonds in Salt
      • Electronegative O pulls e- from H in water
      • This causes a partial (+) charge on the H, and a partial (-) charge on the O
      • Partial charges are indicated by lower case deltas (d)
      • The bonds between O and H are polar covalent bonds
      3. Polar Covalent Bonds   
    • Van der Waals
      • Short-lived charges on the surface of molecules induce opposite charges in adjacent molecules: Van der Waals ‘bonds’
    • Water is Polar
      • Water is a dipole
      • O pulls electrons from H
      • O end is partially (-), H ends are (+)
      • Partial charges interact
      • H’s attracted to O’s
      • Causes water to self-associate
    • Water Forms Hydrogen Bonds
    • Properties of water 1. Transparency 2. Water is “Sticky” Cohesive – sticks to itself Adhesive – sticks to other things creating a Meniscus 3. Solvent Properties 4. Thermal Properties 5. B uffering agent
    • Transparency: light can pass through water
      • • Light reaching the chlorophyll molecules within a plant cell.
      • • Light passing through the vitreous humour and aqueous humour of the eye to reach the retina.
      • • Light passing through aquatic habitats allowing vision for these organisms
    • Cohesion: because of the hydrogen bonds the water molecules stick together
      • At a surface, the cohesion of water molecules makes it difficult for small objects to break through. This creates niche opportunities both above and below the surface.
    •  
    • Water has High Surface Tension
      • Water sticks to itself strongly and so has high surface tension
        • Forms meniscus
        • Forms droplets
        • Small animals can ‘skate’ on surface
    • Solvent Properties
      • Many different substances dissolve in water because of its polarity. Inorganic particles such as sodium ions and organic substances such as glucose can dissolve.Causes ions to come apart
      • Makes ‘hydration shells’ of water around an ion
    •  
    •  
    • Thermal Properties
      • • Water temperatures tends to remain fairly stable.
      • • As temperature rises the energy is absorbed by the many hydrogen bonds.
      • • Therefore water is a useful substance for living things both physiologically and ecologically.
      • Physiology: Cooling effects
      • • Blood (water in the plasma) can carry heat away from hot parts of the body to the cooler parts.
      • • Water can evaporate at temperature below boiling. Heat energy can absorbed by the water molecules. They enter the vapour phase and carry away heat from the body surface. Hence the process of sweating and panting.
    •  
    • Ecological effects: •Oceans, lakes and ponds have fairly stable temperature which means that organisms that live in them need not waste energy on thermoregulation. Surrounding air temperatures may show marked changes but water water in the same vicinity will remain relatively stable
      • • In natural habitats water rarely boil because it takes so much energy to break all the hydrogen bonds. However there are some organisms that thrive in high temperatures, the so called extremophiles.
      • • Water has a high freezing point. As water freezes the molecules for a crystal structure less dense than water itself. Therefore ice floats. This important if you are a fish or a polar bear.
    • Water acts as Buffers
      • Acids release protons ( proton donors )
      • Acid molecule H + + Anion
      • Bases absorb protons ( proton acceptors )
      • Base is an anion
      • Anion + H + Acid
      • Example:
        • HCl (acid – actually a gas, dissolves in water) H + + Cl -
        • NaOH (base - solid dissolves in water) Na + + OH -
    • pH is Very Important
      • Cell function is greatly dependent on pH
      • Normal physiological pH is usually close to pH 7.4
      • Minor deviations from physiological pH can be very devastating to biochemical reactions (and therefore, to life processes)
    • Buffers Minimize Changes in pH
      • Buffers are molecules that act as acids or bases or both
      • They are weakly (i.e., incompletely) ionizing
      • Many buffers are both acid and base at the same time
      • Bicarbonate ( HCO 3) is an important buffer in vertebrate blood:
    •  
    •  
    •  
    • Organic chemistry
      • The branch of chemistry that specializes in the study of carbon compounds
      • Organic molecules are molecules containing carbon and hydrogen (except hydrogencarbonates, carbonates and oxides of carbon
    • Macromolecules
      • Carbohydrates
      • Lipids
      • Proteins
      • Nucleic Acids
    • 1. Carbohydraytes
      • Are organic compounds made of sugars and their
      • monomers.
              • Monosaccharides Single units callled monomers.
              • Disaccharides 2 monomers joined.
              • Polysaccharides long chains of repeating units
    • The ring structure of Glucose and Ribose
      • Below is the structure of Glucose .
      • • C 6 H 12 O 6
      • • Carbon 5 is connected to Carbon 1
      • • Each Carbon has an -OH group
      • • Each Carbon has an -H (C6 has 2)
      • Properties of Glucose
      • • soluble
      • • sweet
      • • reducing sugar
      • • monomer of Starch/ Glycogen
    • This is the structure of Ribose
      • • C 5 H 10 O 5
      • • Carbon 1 is attached to Carbon 4
      • • Each Carbon has a -H group (C5 has 2)
      • • Each Carbon has a -OH group
      • Properties of Ribose
      • • soluble
      • • part of the structure
      • of nucleic acids
      • • e.g. Deoxy ribo nucleic acid
    • Galactose
      • Sugar which is less sweet than glucose.
      • It is found in dairy products, in sugar beets and gums. When combined with glucose, through a dehydration reaction, the result is the disaccharide lactose found in most milks.
    • Difference in the Structure Galactose Glucose
    • B. Disaccharides
      • Are double sugars that contain two monosaccharides.
      • Are formed through the process of condensation synthesis.
      • Monosaccharide + monosaccharide  Disaccharide
    • Condensation and Hydrolysis Reactions
      • Principle: Monomer + Monomer = Polymers
    • Table sugar Glucose + Fructose Sucrose Present in milk. Glucose + Galactose Lactose Brewing beer. Glucose + Glucose Maltose Examples Monomers Disaccharide
    • C. Polysaccharides
      • Macromolecules that are polymers of a few hundred or thousand monosaccharides .
      • Important in :
        • Energy Storage
        • 2. Structural support
      • Examples
              • Starch (energy)
              • Glycogen (energy)
              • Cellulose (structure)
    • Role of Carbohydrates in
      • In Plants
      • Fructose may play a role in photosynthesis/and aid in seed dispersal
      • Sucrose helps with the movement of water in the plant
      • Cellulose structure of the cell wall
      • In Animals
      • Glucose - energy
      • Lactose - source of food
      • Glycogen - energy storage
    •  
    • 2. Lipids
      • Diverse group of molecules that are non-polar .
      • Constructed from a glycerol attached to 3 fatty acid chains.
      • Glycerol is a 3-C alcohol.
      • Fatty acids are hydrocarbons with a carboxyl group at one end. Sometimes they are called carboxylic acids.
      • Hydrocarbon tail is extremely hydrophobic.
    • Lipid Molecule Structure
      • Glycerol
      • 3 carbons
      • each has a -OH group
      • others are single C bonds
      Fatty Acid This is a long chain of CH 2 with an carboxyl group (COOH) at the end . The other end is methyl group CH 3
    •  
    • Lipids: The Functions of Fats
      • Energy storage - one gram of fat stores 2x the energy of a carbohydrate..
      • 1gram of fat 9 calories
      • 1 gram of Carbohydrates has 4 calories
      • Cushions vital organs in mammals.
      • Insulation
    • 3. Proteins
      • They are the most diverse type of macromolecule. They are responsible for:
      • 1. Structural support (collagen)
      • 2 . Catalyzing reactions (enzymes)
      • 3 . Transport (hemoglobin)
      • 4 . Signaling (Hormones)
      • 5. Cellular response to chemical stimuli ( receptors )
      • 6. Movement (contractile proteins).
      • 7. Defense (antibodies).
      • Amino acids are the building blocks of proteins.
      • AA + AA + AA … = protein
      • Every amino acid has:
        • Terminal Hydrogen
        • Carboxyl Group
        • Amino group
        • Variable group
        • (R group)
    •  
    •  
    •  
    • Structure of Proteins
      • The complex structure of proteins is explained by referring to 4 levels of organization
      • Primary
      • Secondary
      • Tertiary
      • Quaternary
    • Structure of Proteins
      • A. Primary structure:
        • The order/ number of amino acids in a polypeptide chain.
        • Linear shape
    • Secondary Structure:
      • Folding in the primary structure is caused by
      • charged groups on the amino acid chain.
      • These charged groups include :
          • Hydrogen bonds
          • Ionic bonds
          • Covalent bonds. (disulphide bridge)
      • These bonds cause the primary structure of the polypeptide to fold and coil into some characteristic ways :
          • Alpha Helix
          • Beta pleated sheets
    •  
    • Alpha helix proteins  
      • Alpha-helix:
      • Formed from Hydrogen Bonds
      • Notice the regular helix shape.
    • Beta-pleated sheets :
      • Flat, zig-zag structure
      • A number of chains which are hydrogen bonded together
      • Forms a sheet
      • Example : Fibers in in silk
    • Modeling Protein Folding
    • Folding
    • Polar and non polar regions
      • Are used in membrane channels
      • Polar sections allow ions (which normally can not pass through the hydrophobic layers).
      • Polar amino acids are positioned on external surface and line the protein channel for facilitated diffusion
    • Polar amino acids in enzymes
    • Tertiary Structures
      • Tertiary structure is the three-dimensional conformation of a polypeptide.
      • In other words there are folds in a polypeptide chain.
      • The polypeptide folds just after it is formed in translation.
      • The shape is maintained by intramolecular bonds
      Lysozyme
    •  
      • Hydrogen bonds
      • Ionic Bonds
      • Disulphide Bridges
      • These bonds form between the R groups of widely spaced amino acids.
    • Quaternary Structures:
      • Quaternary structure is the linking together of two or more polypeptides to form a single protein
      •  
    •  
    • Proteins are the stable, folded 3D structures of polypeptides. Polypeptides are the chains of amino acids that fold into proteins.
    • Fibrous Proteins  
      • Insoluble in Water
      • Structural (support/strength)
      • Example
            • Collagen (tissue strengthening)
            • Keratin (hair/nails)
            • Elastin (skin)
      Each color represents an alpha helix
    • Globular Proteins
      • Can be soluble in water
      • Functional (enzymes and antibodies)
      • Examples
        • Amylase (digestion of starch)
        • Insulin (blood sugar regulation)
        • Hemoglobin (carry O 2 )
        • Immunoglobulins (antibodies)
    • 4. Nucleic Acids
      • Protein conformation is determined by primary structure. Primary structure is determined by genes - hereditary units that consist of DNA.
      • There are two type of nucleic acids:
        • DNA
        • RNA
    • Nucleic Acids
      • Nucleic acids are polymers of nucleotides linked together.
      • Nucleotides are the monomers; they have:
        • 5-C sugar (pentose: ribose or deoxyribose)
        • Phosphate group
        • Nitrogenous base
    •  
    •  
    •  
    • A strand of nucleotide is joined by covalent bonds
    • DNA is a double strand of polynucleotide
    • When DNA replication
    • A. RNA : Ribonucleic Acid
      • Functions in the actual synthesis of proteins coded for by DNA.
      • Usually single stranded.
      • Flow of genetic information is:
      • DNA  RNA  protein
    •  
    • DNA : Deoxyribonucleic Acid
      • Contains coded information that programs cell activity.
      • Contains directions for its own replication.
      • Is copied and passed from one generation of cells to another.
      • Has genes that contain instructions for protein synthesis.
      • Usually double stranded (double helix).