Chapter 2, Section 1 Chemical Compounds in Cells

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Chapter 2, Section 1Chemical Compounds in Cells

• Tuesday, September 29, 2009
• Pages 52 -- 55

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Objectives

• Describe the four main kinds of organic molecules
  in living things.
• Explain how water is essential to the functioning
  of cells.

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Vocabulary Words

• Element
• Atom
• Compound
• Molecule
• Organic compound
• Inorganic compound
• Protein

• Amino acid
• Enzyme
• Carbohydrate
• Lipid
• Nucleic acid
• DNA
• RNA

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Elements and Compounds

• Element
• Any substance that cannot be broken down.
• Atom
• The smallest unit of an element.
• Compound
• Made up of 2 or more elements chemically
  combined.
• Molecules
• The smallest unit of a compound.

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Organic/Inorganic Compounds

• Organic compounds are compounds that contain
  carbon.
• Proteins, carbohydrates, lipids and nucleic acids
  are important groups of organic compounds.
• Inorganic compounds are compounds that do not
  contain carbon.
• Water, sodium chloride are examples of inorganic
  compounds.
• Exception is Carbon Dioxide.

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Proteins

• Proteins are large organic molecules made up of
  carbon, hydrogen, oxygen, nitrogen, and sometimes
  sulfur.
• Cells use protein to form parts of the membrane.
• Cells make up many of the organelles.
• Proteins also build body structure (muscles).

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Protein Structure

• Protein molecules are made up of amino acids.
• It is the various combinations of 20 common amino
  acids.
• The type of amino acid and the order in which
  they are linked will determine the type of
  protein.

Peacock feathers are made mainly of proteins.
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Enzymes

• An enzyme is a type of protein that speeds up a
  chemical reaction in a living thing.

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Carbohydrates

• A carbohydrate is an energy-rich organic
  compound.
• Made up of carbon, hydrogen, and oxygen.
• Sugars and starches are examples.
• Carbohydrates help make up cell walls and cell
  membranes.

These are unstained starch granules from a potato.
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Lipids

• Lipids contain the most energy (more than
  carbs!).
• They are energy-rich organic compounds made up of
  carbon, hydrogen, and oxygen.
• The cell stores energy in lipids for later use.

Lipids are critical to cell division and fusion.
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Nucleic Acids

• Nucleic Acids are large organic molecules made of
  carbon, oxygen, hydrogen, nitrogen, and
  phosphorus.
• Nucleic Acids contain the instructions the cells
  need to carry out its functions.
• 2 kinds of nucleic acid.

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Water and Living Things

• Water makes up roughly 2/3 of your body.
• Chemical reactions will not take place without
  water.
• Water helps cells keep their size and shape.
• Water helps stabilize our internal environment.

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Homework

• Workbook, 2.1 -- Due on Thursday, 10/1.
• Make a Venn Diagram comparing and contrasting DNA
  and RNA on the paper provided. Use color -- this
  will be posted on the wall! -- Due Wednesday,
  9/30.