Chapter 5: The Working Cell

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Chapter 5 The Working Cell
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What We Will Cover In Chapter 5

• We will discuss the concepts of conservation of
  energy and conservation of mass
• We will compare and contrast combustion vs.
  cellular respiration
• We will discuss the role of ATP as the chemical
  currency of the cell
• We will describe the biochemistry of enzymes
• We will look at anabolic and catabolic reactions
• We will compare and contrast passive and active
  transport
• We will discuss osmosis
• We will define and describe exocytosis and
  endocytosis
• We introduce cell signaling and signal
  transduction in cells

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Fundamental Thermodynamics Conservation of
Energy and Conservation of Mass
Conservation of __________. The principle that
matter can neither be ___________ nor
__________________. Conservation of
_____________. The principle that energy can
neither be created nor destroyed ----------------
------------------------------

Combustion Exploding gasoline to power a
machine. Results in the production
of _______________, _____________, and
_____________.
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Cells are Like the Engine of an Automobile
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Automobiles convert 25 of the energy in gasoline
molecules into moving a car down the road. Our
bodies are better than that. We convert about
40 of the potential energy in _____________into
cellular energy in the form of ATP. This is the
job of the ______________.
Cellular respiration takes place in the
mitochondria of our cells
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Energy and Weight Gain
There are millions of diets outlined in millions
of books but in biological terms, energy
____________ must equal energy ___________ or
the body will store energy in the form of
_____________.
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Whats in a Calorie?
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A _____________ is the unit by which the
_______________ in food is measured.
Raises 25 ml of water by 7 degrees celsius
Raises 25 ml of water by 1 degree celsius

1 Cup Broccoli 25 calories 1 oz Peanuts 165
calories
An Analytical Calorimeter
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Gaining Those Calories
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A _____________ is the unit by which the
_______________ in food is measured. This energy
can either be used for work or be stored as fat
for another day.
Consider the types of foods that pack the most
calories and think about how these calories, if
you dont use them might be converted to fat.
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Burning those Calories
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To maintain a consistent _________ if you consume
more calories than your basic body processes
demand, you will need to __________ to balance
out the input equals outgo equation.
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ATP and Cellular Work
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The _______________ and other energy molecules
we obtain from ________________ do not drive the
work in our cells directly. Instead ,the
chemical energy released by the breakdown of food
during cellular respiration is used to generate
molecules of ATP.

We receive our pay in the form of a check or
electronic deposit. Those checks or deposits
need to be converted to cash. It is cash that
buys tomatoes at the farmers market.
________is the energy currency of the cell.
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Cellular Respiration and ATP
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Cellular respiration is the process by which
____________ molecules are converted into
________ within the mitochondria of the cell.
Then, the cell can spend those ATP molecules to
do the work of the cell.
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ATP and Cellular Work
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Adenosine triphosphate (ATP) is the energy
currency of the cell. It is actually the last
phosphate group that powers the molecular work of
the cell. ATP is recyclable. Once ATP is spent,
__________ is converted to (ATP) using the
energy gained from __________.
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(ATP) Phosphate Transfer
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The transfer of the terminal ____________ group
in ATP results in an addition of chemical energy
used to power cellular reactions.
___________serves as a biological form of
chemical energy. Think of the role of
batteries used to power a radio, flashlight, or
other useful household item.

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Phosphate Transfer
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• Transferring the terminal phosphate group in ATP
  results in the of chemical energy used to power
  cellular reactions.
• Examples of ATP mediated cellular work.
• ____________ Work
• _____________ Work
• 3. _____________ Work

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Cells are Very Industrious
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A hard working cell recycles all of its ATP
about once a minute. This amounts to about 10
million ATP molecules spent and regenerated per
second -per cell !

Cellular _____________ is the biochemical
conversion of ____________________ to
____________ and takes place in the
_______________________ of the cell.
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Enzymes Drive Metabolism
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The total of all the chemical reactions that
occur in a living organism is called ___________.

Enzymes speed up chemical reactions and thus
__________ metabolism.
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Enzyme Mediated Chemical Reactions(Activation
Energy)
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Enzymes ________________ chemical reactions
by _______________ the amount of _____________
energy required to convert _________ to products
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Enzyme Mediated Chemical Reactions Anabolism and
Catabolism
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________________ describes a biochemical reaction
where enzymes link small molecules together to
form larger ones. For example, the
linking together of _______ and ________ to form
____________ is an anabolic reaction.
__________________ describes a biochemical
reaction where enzymes break larger molecules
into smaller molecules For example, the
splitting of ____________ to form galactose and
_________________ is a catabolic reaction.


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Enzyme Mediated Chemical Reactions(Activation
Energy)
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Enzymes break ______________by adding energy
to the compound. They do this by putting the
reactants under some kind of physical or chemical
stress.
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Enzyme Mediated Chemical Reactions
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• Each enzyme is specific for a specific chemical
  ____________. The three dimensional
  ______________ of the enzyme makes it just the
  perfect fit for a specific compound, in this case
  _______________.
• When the substrate docks into the ___________
  ____________ the enzyme inserts a water
  molecule to break the bond between the monomers.
  

Observe that the enzyme is not _____________ or
________________ as a result of driving the
reaction. Once the job is done, the enzyme is
ready for another reaction.
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The Working Membrane
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The many ___________ embedded in the plasma
membrane perform a variety of functions
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Passive Transport Diffusion Across Membranes
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Diffusion The tendency for molecules of any
substance to spread out into the available space.
In other words, a substance will diffuse from
where it is __________concentrated to where it
is less __________________.
There is no energy required for passive
transport, that is why it is passive transport
and not active transport.
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A Cellular Example of Diffusion
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Diffusion of carbon dioxide __________ of a
cell and diffusion of Oxygen __________ a cell.

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Osmosis
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Osmosis The passive transport of ___________
across a selectively permeable membrane is called
osmosis.
Tonicity is only useful for comparing the
solute concentration of two solutions. -----------
--------------------------------- Unrelated
Analogy The statement I am taller really has no
meaning unless compared to the height of someone
else.
____________solution the solution with the
higher concentration of solute. _____________solu
tion the solution with the lower concentration
of solute. _______________solution two
solutions with equal concentrations of solute.
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Water Balance in Animal Cells
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1. In an _____________solution the cell retains
its original shape the flow of water in equals
the flow of water out. 2. In a
________________ solution cell explodes (lyses)
because the flow of water in exceeds the flow of
water out. 3. In a ______________ solution
the cells shrivels up because the flow of water
in is less than the flow of water out.

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Water Balance in Plant Cells
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• In an isotonic solution the plant wilts a bit
  because there
• is not enough turgor pressure exerted on the
  cell wall by the plasma
• membrane to keep the entire plant erect.
• In a hypotonic solution the plant is healthy and
  erect because of the
• turgor pressure exerted on the cell wall by the
  plasma membrane.
• In a hypertonic solution the cells (and maybe the
  plant) will die
• due to plasmolysis. Plasmolysis is the tearing
  away of the plasma
• membrane from the cell wall.

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Active Transport Pumping Molecules Across
Membranes
In contrast to passive transport, ___________
____________ requires that a cell expend energy
( ) to pump molecules from a lower
concentration to a higher concentration.
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Analogies for Passive and Active Transport

____________transport or _____________describes
the escaping sheep going through an unlocked
gate. _____________ describes the passive flow
of water from a overflowing dam into New Orleans.
Active transport would describe the __________
that would be necessary to round up the sheep and
pump the water out of the city.
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Summary of Passive and Active Transport
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Exocytosis and Endocytosis of Large Molecules
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Packets of molecules are released by the cell
when _______________fuse with the cell wall, open
up and spill their contents outside the cell.
This is called __________________.
The opposite process takes place when a cell
takes in material from its surroundings. This is
called ______________. The plasma membrane forms
around the material and pinches off inside the
cell.
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Exocytocis and Endocytosis (Phagocytosis)
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http//www.stolaf.edu/people/giannini/flashanimat/
cellstructures/phagocitosis.swf
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Cell Signaling
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• Cells communicate through a process known as
  signal __________________.
• 1. A chemical produced in the body called a
  ________ binds to a specific protein receptor in
  the membrane.
• This outside signal then triggers some activity
  in that cell.

A good example of cell signaling or signal
transduction is the effect of _____________
otherwise known as ____________ on muscle cells.
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Thats All for Chapter 5
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