BIOLOGY LECTURE NOTES CHAPTER 7 CELL STRUCTURE AND FUNCTION

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BIOLOGY LECTURE NOTESCHAPTER 7CELL STRUCTURE
AND FUNCTION
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• HISTORY OF CELL STUDY
• Anton van Leeuwenhoek first microscope
• observed animalcules.
• Robert Hooke named the cell based on
• observations of cork.

CORK
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• Schleiden All plants are made of cells.
• Schwann All animals are made of cells.
• 5. Virchow All cells come from pre-existing
  cells.
• Cell Theory
• All living things are made of cells.
• Cells are the basic unit of structure and
  function.
• (smallest unit of life)
• 3. New cells are produced from existing cells.

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• Organisms can be unicellular or multicellular.
• If multicellular, the cells become specialized to
  do
• specific jobs.
• Cells become organized with a division of labor.
• Cells Tissues Organs Organ
  Systems
• Organisms

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Levels of Organization
Muscle cell
Smooth muscle tissue
Stomach
Digestive system
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• CELL COMPARISON
• PLANT CELL ANIMAL
  CELL
• cell walls cellulose 1. no cell
  walls
• chloroplasts 2. no
  chloroplasts
• large vacuoles 3. small
  vacuoles
• no centrosomes 4. centrosomes
• no lysosomes 5. lysosomes
• often rectangular 6. irregular
  shapes

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• Two organelles of importance in obtaining
• and using energy are CHLOROPLASTS
• and MITOCHONDRIA.
• (Both organelles contain their own DNA which
• suggests they may have been independent organisms
• at one time.)
• CHLOROPLASTS
• Found only in plants.
• Plants use the energy of light to convert water
  and
• carbon dioxide into oxygen and high-energy
• carbohydrates sugars and starches.

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• 6 CO2 6 H2O C6H12O6 6 O2
• (Equation for photosynthesis.)
• Chloroplasts contain sac-like membranes
  known as thylakoids where the suns energy is
  trapped and transferred to sugar-producing
• reactions.

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• MITOCHONDRIA
• Found in all living cells.
• Site of cellular respiration the process that
• releases energy by breaking down food molecules
• in the presence of oxygen.
• 3. 3811 calories in 1 gram of glucose or 3.811
• kilocalories (what we call calories)
• C6H12O6 6 O2 6 CO2 6
  H2O ATP
• This is called cellular respiration.

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• ATP adenosine triphosphate
• A chemical fuel that is formed in mitochondria.
• Energy is released gradually by changing
• ATP ADP P.
• The bond is a high-energy bond.
• ADP P ATP restores the
  high-energy bond.
• In the presence of oxygen, one molecule of
  glucose
• produces 36 ATPs. This represents 38 of the
• energy found in glucose. The other 62 is
  released
• as heat lost to living things.

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MITOCHONDRION
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Cytoskeleton
Maintains cell shape and functions in cell
movement.