17.0 Analyze the Relationships Within Living Systems

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Transcript 17.0 Analyze the Relationships Within Living Systems

Bell Work: 1/14/14
Please pick up your Binder, pick up today’s
notes, find your assigned seat and log-in to
LEARN on your Laptop.
1.
2. Please open the Cell Functions topic and
open the Plants Cells vs. Animals & Transports
Power Point and review to complete you notes.
17.0 Analyze the Relationships
Within Living Systems
17.1 Explain the role of the cell and
cellular processes.
Which of the following cells is a
Prokaryote and a Eukaryote?
A.
B.
What is a cell?
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The smallest unit that
can carry all the
processes of life
What is the cell theory?
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The basic unit of structure and function
within an organism is the cell
All living organisms are composed or one
or more cells
Cells come only from existing cells
That cells are the smallest life forms
capable of self-replication.
Why are cells important to
Agriculture?
■
Without the ability to study cells, most of
the advances in agriculture would not have
taken place
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Life processes take place on a cellular level
Everything in the production process of
plants and animals must be understood at
cellular level to make improvements
Cell Types
■
What kinds of cells exist in nature?
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There are only two main categories of cells
that comprise all life forms, no matter how
complicated a life form may appear:
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1. Prokaryotes, and
2. Eukaryotes.
Prokaryote Cells
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Prokaryotes are cells
without a nucleus.
They have genetic
materials but are not
enclosed within a
membrane.
Instead, the genetic
material (DNA) of
prokaryotes floats free
in the cell.
Prokaryote Cells
• These include bacteria and cyanophytes.
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The genetic material is a single circular DNA
and is contained in the cytoplasm, since there
is no nucleus.
Eukaryote Cell
• These are cells
•
with a nucleus.
The genetic
material is
surrounded by a
membrane much
like the cells
membrane.
Eukaryote Cell
• Eukaryotic cells are found in humans and other
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multi-cellular organisms (plants and animals)
also algae, protozoa.
They have both a cellular membrane and a
nuclear membrane
What is an organelle?
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A cell component that performs specific
functions
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Example – nucleus, cell membrane
Cell Membrane
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The outer boundary
of the cell
Gives shape and
flexibility to the cell
Is semi-permeable
Cell Wall
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Only in plant cells
Thicker then the
membrane
Relatively inflexible
Protects and supports
the cell
Cytoplasm
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Semi-fluid material
inside a cell
Helps to keep all
organelles in place
Nucleus
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The cells brain
Contains
chromosomes
Involved in protein
synthesis
Endoplasmic Reticulum (ER)
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Folded membrane
Transports proteins
and other materials
Ribosomes
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The site of protein
synthesis
Can be attached to the
ER or float loose in
the cell
Golgi Body
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Closely stacked
flattened membranes
It is the processing,
packaging and
secreting organelle
Mitochondria
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Breaks down food
molecules and
releases energy
Lysosome
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Contains digestive
enzymes
Digests and rids the
cell of waste
Prevents bacteria and
viruses from invading
Vacuole
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Sack of fluid
surrounded by a
membrane
Stores food, enzymes
or waste.
Animals cells have
many small ones
Plant cells have one
large on
Plant cell vs. Animal cell
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Plant Cells have:
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Cell Wall
One Large vacuole
Plastids (stores food or pigment which give
color to plant)
Plant cell vs. Animal cell
Animal Cell
Plant Cell
cell
cell
Cell Functions
■
Homeostasis and
Transport
Homeostasis
•The stable internal
condition of a living
thing
•Transportation across a
membrane is essential
for maintaining
homeostasis
•Cell membranes help
control homeostasis by
controlling what
substances pass in or
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out.
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Two Types of
Transport
Passive
Transport
•Passive Transport
•Diffusion
•Active Transport
•Osmosis
•Facilitated Diffusion
•Ion Channels
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Diffusion
simplest type of
passive transport
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The movement of
molecules from an
area of high
concentration to an
area of low
concentration
Does not require
the cell to expend
energy
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Diffusion
Principles
■There
is a concentration
gradient-the difference in
concentration of molecules
across a space
■Diffusion
driven by the
kinetic energy the
molecules possess-moves
randomly
■Diffusion
always occurs
DOWN the concentration
gradient from an area of
HIGH concentration to an
area of LOW concentration.
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Diffusion
Principles
■Rate
of diffusion
depends on the
temperature, size, and
type of molecule that is
diffusing
■Small
molecules
diffuse faster than
larger molecules
■Molecules
diffuse faster
at higher temperatures
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Diffusion
Principles
■Diffusion
will
eventually cause the
concentration of the
molecules to be the
same throughout the
space, and the
concentration gradient
will no longer exist
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■When
this occurs
the system is said to
be in a state of
equilibrium
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Osmosis
• Passive Transport
• diffusion of water
across a semipermeable
membrane from an
area of high
concentration to an
area of low
concentration.
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Osmosis
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Terms:
✹ Solute: substance
being dissolved in
solution
✹ Solvent: the
substance in which a
solute is being
dissolved
✹ Solution: a mixture
in which one or
more substances are
uniformly dissolved
in another substance
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Ex: sugar + water mix
Solute = ?
Solvent = ?
Solution = ?
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Net Direction of
Osmosis
When the concentration
of solute molecules is
higher outside the
cell, the solution is
hypertonic to the
cytosol.
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Water will move out
of the cell
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Net Direction of
Osmosis
When the concentration
of solute molecules is
lower outside the cell,
the solution is hypotonic
to the cytosol.
Water will diffuse into
the cell
When a cell bursts it is
called cytolysis
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Net Direction of
Osmosis
When concentration of solute
molecules outside the cell is
equal to that inside the cell,
the solution is isotonic to the
cytosol.
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No net movement
of water, water
diffuses in/out at
equal rates
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Net Direction of Osmosis
Red Blood Cell
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