Transcript Cells

Cells
The Basic Unit of Life
Cytology:
The Study of Cells
Terms
• Cell – the basic unit of life; all living things
are made of cells
• Cell wall – firm structure outside of plant
cells made of cellulose that support the cell
• Chlorophyll – green pigment that traps light
energy used for photosynthesis
• Chloroplast – organelle in plant cells where
photosynthesis takes place
• Cilia – short, hair-like structures some cells
have for movement
• Compound light microscope – instrument
that magnifies an object by using light and
lenses
• Cytoplasm – cell’s ‘fluid’
• Electron microscope – instrument that uses
magnets and electrons to magnify very
small objects
• Eukaryote – a cell with a nucleus
• Flagella – a whip-like ‘tail’ some cells have for
movement
• Golgi – membrane sacs that receive and
repackage proteins
• Mitochondria – organelle that produces energy
for the cell by breaking down glucose (sugar)
• Multicellular – an organism made of many cell
that are specialized
• Nucleus – organelle that contains the genetic
code (DNA)
• Organ – a group of tissues that function together
• Organelle – a structure found in eukaryotic cells
that performs a specific function; surrounded by
a membrane
• Organ system – a group of organs that function
together
• Plasma membrane – the boundary between the
cell and it’s environment; controls what gets in
or out
• Prokaryote – a cell without a nucleus
• Ribosome – an organelle that produces proteins
for the cell
• Rough endoplasmic reticulum – produces
proteins for the cell
• Smooth endoplasmic reticulum – produces
lipids for the cell
• Tissue – a group of cells that function
together
• Unicellular – a cell composed of only one
cell; Paramecium, amoeba
• Vacuole – sac-like organelle that stores water,
food or poisons
ACOS - 4
•
Describe the similarities and differences of
cell organelles using diagrams and tables
including– cell membrane, cell wall, nucleus,
ribosome, smooth endoplasmic reticulum,
rough endoplasmic reticulum, Golgi body,
vacuole, chloroplast, and mitochondria
ACOS - 4
• Classify organisms as prokaryotic or eukaryotic
• Identify and define similarities and differences
between the 5 kingdom and 6 kingdom
classification systems
ACOS – 5
• Identify cells, tissues, organs, organ
systems, organisms, populations,
communities, and ecosystems as levels of
organization in the biosphere
– Recognize that cells differentiate to
perform specific functions
• Ex. Ciliated cells produce movement, nerve
cells conduct electrical charges
ACOS - 2
• Describe cell processes necessary for
achieving homeostasis, including active and
passive transport, osmosis, diffusion,
exocytosis, endocytosis
– Identify functions of carbohydrates,
lipids, proteins, and nucleic acids
– Compare reactions of plant and animal
cells in isotonic, hypotonic and
hypertonic solutions
ACOS - 2
– Explain how surface area, cell size,
temperature, light and pH affect cell
activities
– Apply the concept of fluid pressure to
biological systems
• Blood pressure, turgor pressure, bonds,
strokes
Cell Theory
• Most important tool to cytology:
Microscopes ACOS 1
• Light microscope - uses
lenses to magnify light
through the object
• Electron microscope uses magnets to focus a
beam of electrons through
the object
Types of Microscopes
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Light:
Uses light and lenses
Only magnifies 1500 x
Live
• Electron
• Uses magnets and
electrons to magnify
• Magnifies 1,000,000 x
• Not alive
Cell Theory ACOS - 4
• 1665: Robert Hooke: looked at cork
• Called little spaces ‘cells’
Anton Van Leeuwenhoek, 1678;
Looked at pond water, teeth scum
Saw one-celled ‘animicules’
(bacteria)
Spirochete
Cell Theory ACOS – 4
• Schleiden – botanist
– ‘plants are made of cells’
Cell Theory ACOS – 4
• Schwann – zoologist/physician
– ‘animals are made of cells’
Cell Theory ACOS – 4
• Virchow – physician
– ‘cells come from other cells’
– ‘cells cause disease’
Main Parts of a Eukaryotic Cell:
1.
2.
3.
Cell membrane (plasma membrane)
Cytoplasm and organelles
Nucleus
Cell Membrane
• Controls (regulates) what enters and exits
the cells
Cell Membrane
Cytoplasm and Organelles
• Cytoplasm = ‘ cell’s fluid’; mostly water
Organelles
Ribosomes = manufacture proteins
Organelles
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Rough Endoplasmic
reticulum
Rough ER
Folded membrane that forms a
network of tubes and
compartments + ribosomes to
make proteins
Smooth Endoplasmic Reticulum
• Endoplasmic reticulum
that does not have
ribosomes
• Manufactures
– Lipids,
– Steroid hormones
Organelles
Golgi body - membrane sacs that
store and repackage proteins
•
Some proteins are ‘shipped
out’ of the cell for use by
other cells
– Hormones; insulin
Quiz: Cells 1
Which device would be used to observe ribosomes?
–
Magnifying lens; light microscope, electron microscope, petri dish
Which device would be used to transfer small amounts of liquids?
Petri dish, pipette, beaker, graduated cylinder, flask
Which device would be best to measure mass?
balance; graduated cylinder, flask, pipette
Which structure manufactures proteins for the cell?
smooth ER; rough ER; cell membrane; cytoplasm
Which structure transports proteins around the cell?
ribosomes; smooth ER; cytoplasm; rough ER
Organelles
Vacuoles - sacs that temporarily store:
– Food
– Water
– Poisons (plants)
Energy Organelles:
1.
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Mitochondria
Cellular respiration - sugar (glucose) is broken
down to release energy
Might = energy
Mighty mitochondria
Energy Organelles:
2. Chloroplasts
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Contain chlorophyll
Photosynthesis
Chloroplasts:
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Capture the sun’s energy and use it to:
Photosynthesis -
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Change carbon dioxide (CO2) and water
(H2O) into glucose (food)
Cytoplasmic streaming
Photosynthesis
CO2
H2O
Nucleus
•
1.
2.
Nucleus: membrane-bound organelle
towards the center of the cell
Enclosed by a membrane (membrane
bound)
DNA = determines inherited traits
Movement Organelles
• Cilia – hair-like projections on the
outside of some cells for movement
– Short
– ‘oars’
– Paramecium
– Lungs
Paramecium
Cilia
Paramecium
Stentor
Vorticella
Movement Organelles
• Flagella
• Whip like ‘tail’
• One or only a few
• Movement
Euglena
Euglena-Flagella
Prokaryotic or Eukaryotic
• Prokaryotic
• Eukaryotic
• No nucleus
• No organelles
• Bacteria
• Nucleus
• Organelles
• All other organisms
Bacteria = Prokaryotes
Eukaryote
ACOS – 5
• Hierarchy of life – life becomes
increasingly complex
Hierarchy of
organization
Ecosystems
Communities
Populations
Organisms
Organ Systems
Organs
Tissues
Cells
Organism
Tissue
Organ
Cell
Organ
System
Plant Cells
• Cell Walls = outside covering
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Cellulose
Strength
Support
‘Square’ shape
Plant Cells
• Chloroplasts = contain chlorophyll for
photosynthesis
• Capture sun’s energy
Plant Cells
• Large water vacuoles = storage of water
• ‘Water balloons’
• Keeps plants cells ‘full’
Animal Cells:
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Membranes
Ribosomes
ER
Vacuoles
Golgi
Mitochondria
• Nucleus
• Cilia (some)
• Flagella (some)
Plant Cells
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Cell Membrane
Ribosomes
ER
Vacuoles
Golgi
Mitochondria
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Nucleus
Cell Wall
Chloroplasts
Large water
vacuoles
• No cilia, flagella
• Animals:
– Membrane
– Ribosomes
– ER
– Vacuoles
– Golgi
– Mitochondria
– Nucleus
• Plants:
– Membrane
– Ribosomes
– ER
– Vacuoles
– Golgi
– Mitochondria
– Nucleus
– Cell wall
– Water vacuole
– Chloroplasts
Cell Energy
Respiration
Photosynthesis
Photosynthesis
• Photosynthesis – process of combining carbon
dioxide and water by capturing the energy from
light
• Light energy is stored in the bonds of carbon
and hydrogen in the glucose
Photosynthesis
Carbon
dioxide
Water
6 CO2 + 6 H2O
Glucose
Oxygen
C6H12O6 + 6 O2
Photosynthesis
Carbon
dioxide
Water
6 CO2 + 6 H2O
Reactants
Glucose
Oxygen
C6H12O6 + 6 O2
Products
Photosynthesis
• What happens to the glucose?
• Used immediately by the plant for energy
– Growth, reproduction (fruits)
• Leftover glucose is stored by the plant as
starch (roots, stems, leaves)
• Animals eat the plants (and the glucose and
starch); food chain
Food Chains
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Energy flows from the:
Light, to the…
Plants, to the…
Herbivores, to the …
Carnivores, to the …
Scavengers.
Carbon dioxide returns to the air, back into
the plants
Respiration
• Process of producing energy
– Combine oxygen with glucose
• Cells use the energy for:
– Movement
– Mitosis
– Active transport of substances out of the cell
– Making proteins and DNA
Glucose
Oxygen
Carbon dioxide
Water
C6H12O6 + 6 O2
6 CO2 + 6 H2O
Reactants
Products
Photosynthesis
Plants and Algae
6CO2 + 6H2O
C6H12O6 + 6O2
Respiration
Animals and Fungi
Aquatic Food Chains