Vocabulary Review

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Vocabulary Review

• Competency 2
• Chemical Basis of Life

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Competency 2 Chemical Basis of Life

• A. Identify the characteristics of living things
• B. Describe differentiate between covalent
  ionic bonds using examples of each
• C. Describe the unique bonding characteristics
  of water that makes it an essential component of
  living systems.
• D. Classify solutions using the pH scale
  relate the importance of pH to organism survival.
• E. Compare the structure, properties functions
  of carbohydrates, lipids, proteins, nucleic
  acids in living organisms.
• F. Explain how enzymes work identify factors
  that can affect enzyme action

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Characteristics of Life

• Cells
• Reproduce
• Universal Genetic Code
• Grow Develop
• Obtain materials use energy from it
• Respond to environment
• Homeostasis
• Change over time

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Ionic Bond 26

• Transfer (gain or loss) of electrons
• Example NaCl (salt)

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Covalent Bond 27

• Electrons are shared between atoms
• Example H2O

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Water 24

• Essential for life
• Polar covalent bonds hold Hs to the O (give its
  shape Mickey Mouse)
• Universal solvent
• Hydrogen bonds hold water molecules to other
  water molecules
• Cohesion allows insects to walk on water
  (surface tension)

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Water Molecule
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pH Scale

• pH scale determines how acidic or basic a
  substance is.
• Ranges from 0-14
• pH of 7 is neutral
• (pure water)

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Acids 28

• Any number below 7 on the pH scale
• The lower the number, the stronger the acid
• produces H ions (hydrogen)

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Base 29

• Any number above 7 on the pH scale
• The higher the number, the stronger the base
• produces OH- ions (hydroxide)

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Elements in Living Thing

• Oxygen - O
• Carbon - C
• Hydrogen - H
• Nitrogen - N

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Organic Compounds 16

• Compounds that contain carbon
• Found in all living things
• Examples
• Carbohydrates
• Proteins
• Lipids
• Nucleic acids

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Carbohydrate 18

• Sugars (-saccharide mono-, di-, poly-)
• Contain C, H, and O
• Produced during photosynthesis
• Usually end in ose (glucose, sucrose)
• Stored in plants starch
• Stored in animals glycogen
• Quick energy

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CARBOHYDRATES

• monosaccharides - simple ring sugars, glucose and
  fructose
• disaccharides - two monosaccharides combined,
  sucrose and lactose
• polysaccharides - polymers of monosaccharides,
  starch and glycogen

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Glucose 20

• Monosaccharide (simple sugar)
• Hexagon shape - C6H12O6
• Produced during photosynthesis
• Primary energy source quick energy
• carbohydrate

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Protein 25

• Made up of amino acids that are joined together
  by peptide bonds
• Made at the ribosome (translation)
• Polypeptide
• Building blocks for living tissues

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Amino Acids 17

• Building blocks of proteins
• Also called polypeptides

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Lipid 21

• Made up of fatty acids
• Waxes, oils, fats, steroids
• Doesnt mix with water
• Phospholipids make up cell membrane (2 layers)
• Hydrophobic tails water fearing
• Hydrophilic heads water loving

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Lipids

• waxes, oils, fats, steroids (cholesterol sex
  hormones)
• Saturated fats contain no double bonds

Saturated fats solid at room temperature,
unsaturated fats are liquid at room temperature
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Nucleic Acids ( 22)

• Contain the cells information
• DNA RNA
• Made from nucleotides

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Nucleotides 23

• Building blocks of nucleic acids
• Made up of 3 parts
• a 5-carbon sugar
• a phosphate
• a nitrogen base (A, TorU, C, G)

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Enzyme 19

• Protein catalyst that speeds up chemical
  reactions by lowering activation energy
• Remains unchanged can be reused
• Only needed in small amounts
• Usually end in -ase

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Lock and Key Model of How Enzymes Work

• As an enzyme works, it combines with its
  substrate and converts it to product(s).
• Substrate is a molecule upon which an enzyme acts
  (30)

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The Chemistry of Life

• Life is composed of MATTER (anything that
  occupies space and has mass)
• Matter is composed of chemical ELEMENTS
  (substances that cannot be broken down into other
  substances)
• About 92 elements that occur in nature
• COMPOUNDS - substances containing two or more
  elements (ex. chlorophyll)
• ATOMS - smallest unit of matter that still
  retains the properties of an element, each
  element consists of one type of atom

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Structure of the Atom

• Nucleus of the atom contains protons (positive)
  and neutrons (neutral) and the shell of the atom
  contains electrons

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• All atoms of a particular element have the same
  number of protons - this the elements ATOMIC
  NUMBER
• MASS NUMBER or ATOMIC WEIGHT- refers to the sum
  of the protons and neutrons in the nucleus.
• ISOTOPES - variant forms of an element, these
  forms differ in the number of neutrons they
  contain