Transcript Chapter 7 Cells

Guiding Questions
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How do the things we don’t see affect us?
Good things come in small packages. How
does this relate to science?
How does science influence how I live?
How did I use the scientific method today?
Chapter 7: Cell Structure and
Function
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Cell theory
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All living things are made up of cells
Cells are the basic unit of structure and function
All cells come from pre-existing cells
Scientists
Anton van Leeuwenhoek
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Discovered life in pond water.
How did he discover life so small?
He was credited for developing the first
simple…
1674
present
Robert Hooke
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Looked at a cork under a microscope and saw
tiny chambers in it.
He called those tiny chambers (small rooms)…
Cells
Robert Brown
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Saw a dark spot in the middle of the cell and
called it a…
Nucleus
Schleiden
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All plants were made up of cells.
Schleiden weedin’
Schwann
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All animals were made up of cells.
Virchow
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All cells come from pre-existing cells.
break
Structure of Cells
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What regulates what enters and exits the cell?
Cell Membrane
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Lipid bilayer-protection
Protein-act as a pump
Carbohydrates-regulates what goes in and out
(bouncer checks IDs)
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What is only found in plant cells (for added
protection)?
Cell Wall
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Protects cell
Porous-allow material in and out
Pectin-holds other cells together
Cellulose-roughage, adds more protection
Lignin-makes rigid (stronger from wind)
What is the brain of the cell called?
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Nucleus
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Eukaryote- has a nucleus (eu=you, You have a
nucleus)
Prokaryote- does not have a nucleus
(Pro=NO)
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(some single celled organisms)
Nucleolus
Nuclear
membrane
Nucleus
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Chromosomes-contains genetic info. pass
from one generation to the next.
ChromatIN- material IN chromosomes
DNA-(DNA and protein found in chromatin)
RNA and ribosomes- found in nucleolus
Cytoskeleton
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Cyto=cell
Skeleton=structure that supports and shapes
Microtubules-help cell maintain shape
Microfilaments-help function in cell mov’t
and support
Cytoplasmic streaming
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mov’t in the cytoplasm
Organelles
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What is an organelle? How does it compare to
an organ found in a human body?
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Organelle is a “tiny organ” found in cells. Has a
specific job to do for the cell.
Organelles in the Cytoplasm
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Ribosomes- make proteins.
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Free- in cytoplasm
Attached- ribosomes attached to Rough ER.
Endoplasmic Reticulum- assembles and
modifies protein.
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Rough ER- has ribosomes on it
Smooth ER- does NOT have ribosomes on it
More organelles…
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Golgi apparatus- (UPS) packages, modifies,
and distributes carbohydrates and lipids to
proteins.
Lysosomes- Enzymes that digest old and
unused material within a cell.
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(Lysol) clean up crew.
Vacuoles- stores water, salts, carbs., proteins
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Plants have one very larger vacuole
Animals have smaller vacuoles
Organelles still continued…
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Chloroplast- use NRG from the sun to make
food.
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Only found in plants (photosynthesis)
Mitochondria- cells use chemical NRG (from
food) and converts it into NRG the cell can use
for growth, mov’t, and development.
Centrioles- aid in cell division.
Mitochondia “Powerhouse”
Animal Cell
Plant Cell
Cell City Project
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You and a partner will
construct a 3-D model of a
cell in comparison to a city.
You will need to include the
following organelles in your
city.
Type up a reason of what
you chose to represent the
organelles and why you
chose it.
Also include the definitions.
Everything must be neatly
typed.
Cell membrane
cytoplasm
Nucleus
Nucleolus
Nuclear membrane
Free Ribosomes
Attached Ribosome
Smooth Endoplasmic Reticulum
Rough Endoplasmic Reticulum
Golgi Apparatus
Mitochondria
Vacuoles
Lysosome
Centrioles
Movement through Cell Membrane
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Diffusion- mov’t of molecules from an area of
Higher concentration to Lower concentration.
(DHL)
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Doesn’t require cell to use NRG
Moves until reaches equilibrium (actually it keeps
moving equally in both directions)
Osmosis- diffusion of WATER through a
selectively permeable membrane.
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Doesn’t require NRG
Terms
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Permeable- substance can cross the membrane
Selectively Permeable- some subs. are able to
cross membrane while others cannnot
Impermeable- subs. cannot cross membrane.
Diffusion
Diffusion
Osmosis
Osmotic Pressure
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What if too much water and pressure build up?
The plant could internal explode.
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Typically doesn’t happen because of cell wall
prevents cells from expanding too much.
Facilitated Diffusion
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Does not require NRG
Membrane Proteins “help” the diffusion
process.
Active Transport
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Active- requires NRG
Acts like a pump
Endocytosis- infold the membrane around
food.
Phagocytosis-when food is taken in by
endocytosis, the cytoplasm engulfs particles.
Exocytosis- removal of large amounts of
material out of a cell.
Endocytosis
Phagocytosis
Exocytosis
Levels of Organization
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Cells
Tissues-group of similar cells
Organs-group of tissues that work together
Organ system- group of organs
Organism- all organ systems working together.
Cell specialization- cell that perform a special funtion.