Cells: History, Structure, and Function

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Cells History, Structure, and Function
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Robert Hooke

• First to describe cells
• Used a compound microscope
• _______________
• Actually looking at ___________ cells

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Antony van Leeuwenhoek

• Made many microscopes (single lens)
• Describes several types of cells
• First to study living, moving organisms with
  microscope

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Cell Theory

• All living things are composed of ______
• Cells are the basic units of structure and
  function of living things
• New cells are produced from ___________________

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Compound Microscope

• Staph Bacteria Under Compound Microscope

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Electron Microscopes

• Transmission (TEM)
• Specimens cut into very thin slices
• Beam of electron pass through
• Scanning (SEM)
• Samples are dehydrated, put in a vacuum, and
  sometimes coated in materials like gold
• Electrons are bounced off the surface
• Producing 3-D image of surfaces

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Electron Microscope

• Staph Bacteria under Electron Microscope

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Classifying Cells

• Prokaryote
• Lack organized structures
• Circular loop of nucleic acid
• No ______________
• Ex bacteria and blue-green algae
• Eukaryote
• Organized structures called _____________
• DNA in ____________
• Ex animal, plant, fungi, and protists

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Eukaryotic Cells

• Three Regions
• _________________
• __________
• ___________

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Cell Membrane
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Cell Membrane

• Function
• Regulate what comes in and out of cell
• Communication
• Protection and Support
• ________________
• Double layer of lipid molecules
• Fluid Mosaic
• Lipid molecules with other pieces (protein and
  carbohydrates) embedded
• Membrane in constant movement

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Phospholipid

• _________ Head
• Hydrophilic
• Attracted to water
• __________ Tail
• Hydrophobic
• Does not want to be near water

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Membrane Proteins

• Allow larger molecules to pass through membrane
• Can regulate what comes in or out

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Other Molecules

• Cholesterol
• Stabilize the membrane
• Keep non-polar tails from sticking to each other
• Carbohydrate Chains
• _____________________

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Cell Wall

• _____________
• Rigid outer layer covering cell membrane
• Allow plants to support heavy structures like
  flowers
• Contains ________ and various proteins

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Movements Across Membranes

• __________ Transport
• Diffusion (Simple and Facilitated)
• ______________
• ___________ Transport
• Protein Pump
• Endocytosis and Exocytosis
• Movement is controlled by ___________

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Concentration

• Amount of _________ (dissolved substance) in a
  volume of solution
• Expressed as ________________
• Amount of mass is proportional to the
  concentration
• Volume is inversely proportional to the
  concentration

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Passive Transport

• Movement from area of ________ concentration to
  an area of ______ concentration (down
  concentration gradient)
• Requires ______ energy
• Ex Diffusion (Simple and Facilitated) and Osmosis

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Diffusion

• Movement of _____ from high to low concentrations
• Requires no energy
• Continues unit equilibrium is reached

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Facilitated Diffusion

• Solute cannot simply cross cell membrane because
  it is semi-permeable
• Solute movement is aided by ______________________
  
• Allows diffusion of molecules that are too large
  to diffuse through membrane using simple diffusion

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Osmosis

• Movement of ________ from an area of high to low
  concentration
• Requires no energy
• Solutions surrounding cells can be
• ______tonic solution has a high solute
  compared to the inside of the cell
• _____tonic- solution has the same solute as the
  inside of the cell
• _____tonic- solution has a low solute compared
  to the inside of the cell

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Active Transport

• Movement solute from an area of _____
  concentration to an area of _______ concentration
  (across or up the concentration gradient)
• Requires energy (using ________)
• Ex Protein Pumps, Endocytosis, and Exocytosis

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Protein Pumps

• Membrane Protein pumps solute across cell
  membrane
• Solute moving from low to high concentration
• Requires ATP energy

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Endocytosis and Exocytosis

• Movement of large materials across cell membrane
• Endocytosis
• Movement ________ cell
• Pocket of membrane pinches off to form vesicle
  (membrane circle surrounding material)
• Two types
• Phagocytosis- ______________________
• Pinocytosis- _____________________
• Exocytosis
• Movement ________ of cell

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Phagocytosis and Pinocytosis
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Exocytosis
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Cytoplasm

• Everything inside to cell membrane except for the
  _____________
• Includes the fluid cytosol

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Where do organelles come from?

• Thought to originally be prokaryotes that formed
  a symbiotic relationship with another cell
• Evidence
• Many organelles are surrounded by two membranes
• Some organelles contain their own ______

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Nucleus

• _____________ of Cell
• Double membrane w/ many __________
• Contains DNA
• Chromatin
• Chromosomes
• Nucleolus
• Small dark region
• Makes __________

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Ribosome

• Makes __________
• Two subunits made of RNA and protein
• Found free floating in cytoplasm or attached to
  rough ER

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Endoplasmic Reticulum (ER)

• Series of membrane bound canals
• Two Types
• ____________
• Studded w/ ribosomes
• Processes and transports proteins
• _____________
• No ribosomes
• Processes and transports lipids

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Golgi Apparatus

• Stack of flattened pancake-like membranes
• Modifies, packages, and ships out lipids and
  proteins

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Lysosome

• Vesicle filled w/ digestive enzymes
• Breaks down _____________
• Aids in programmed cell death
  (apoptosis)

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Vacuole

• Animals
• Many small membrane bound sacs
• Storage compartments
• Plants
• Usually one large central sac
• Storage sac and helps establish turgor
  pressure to keep plant upright

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Mitochodria

• Double membrane
• Inner membrane highly folded
• _____________of cell (makes ATPs)
• Only inherited from mother
• Contains _______

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Chloroplast

• _______________
• Double membrane
• Converts _______ energy into
  chemical energy
• Contains chlorophyll pigment
• Captures light energy
• Contains ________

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Cytoskeleton

• Skeleton for Cell
• Helps cell maintain shape
• Provides support and protection
• Aids in movement
• Made of microtubules and microfilaments

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Cilia

• Short, hair-like microtubule extensions
• Move in ______ motion
• Move cell or move materials on the surface of
  cells
• Cells usually have many

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Flagella

• Long, whip-like microtubule extention
• Move in ______________ fashion
• Moves cells
• Cells usually only have one or a few

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Centrioles

• Only in ______ cells
• Grouped microtubules
• Aids in ___________
• Moves chromosomes with spindle fibers

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Animal vs Plant Cells
Organelle Animal Plant
Nucleus YES YES
Cytoplasm YES YES
Cell membrane YES YES
Cell wall NO YES
Lysosome YES YES
Ribosome YES YES
ER YES YES
Mitochondria YES YES
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Animal vs Plant Cells (cont)
Organelle Animal Plant
Golgi YES YES
DNA YES YES
Vacuole YES (small, several, only in a few animal cells) YES (large, single)
Cytoskeleton YES YES
Chloroplast NO YES
Centriole YES NO
Flagella YES (some) NO
Cilia YES (some) NO
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Unicellualer Organisms

• Organism made of _______ cell
• Very simple
• One cell performs all the functions of life
• Ex ______________

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Multicellular Organisms

• Organisms made of many cells
• More complex
• Cells _______________ and perform certain
  functions (cell differentiation)
• All cells work together to perform all the
  functions of life
• Ex _____________________

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Levels of Organization
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Levels of Organization (cont)

• __________
• Molecule
• Macromolecule
• ___________
• Tissue- cells working together towards a common
  goal
• ________- tissue working together towards a
  common goal
• Organ system- organ working together towards a
  common goal
• __________