Download Unit 3 Cell Energy Guided Notes

Unit 3 Guided Notes
Enzymes
We get energy from the food we eat by breaking apart the chemical bonds
where food is stored.
_______________ energy is in the bonds,
_______________ energy is the energy we use to do things.
A reaction starts with a _________________ and ends with a _________________
For a reaction to occur there must be an input of energy called:
(graph)
To get energy easily, we need to speed up the reaction by using a molecule
that lowers the energy of activation called an:
(graph)
_______________ are _______________ catalysts and all of our chemical reactions
need them. They are usually _______________
The characteristics of catalysts are:
Enzymes have a special spot in their 3-D structure called the:
An enzymatic reaction occurs when:
The enzyme bonds with the substrate
It changes to fit around the substrate
This is called induced fit
And creates an enzyme-substrate complex
The reaction is completed
The product is released
The enzyme returns to its original shape
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Unit 3 Guided Notes
Certain factors can affect enzymes and therefore reactions
Temperature – cold temperatures make reaction molecules move __________
so the reaction goes ________________
Warm temperatures make reaction molecules move _______________ so
the reaction goes _______________
But if the enzyme gets too hot it _______________ , which is when it
loses its 3D shape and its active site is altered.
This is why a _______________ can kill you.
pH – each enzyme has an optimal range and if it is too acidic or
basic the enzyme will _______________
Enzyme Concentration – the more enzyme in a reaction, the __________ the
reaction proceeds. The less enzyme in a reaction, the
_______________ the reaction proceeds.
Substrate Concentration is the opposite of enzyme concentration, so:
Enzyme Inhibition – Inhibitors stop or slow enzyme’s functioning
___________________ Inhibitors – fit into active site and compete
with the substrate – eventually are released but slow enzyme’s
ability to function. When the body regulates itself this way it is called
_______________ Feedback or Feedback Inhibition
___________________ Inhibitors – bond with enzyme and block or
alter the active site – usually permanent – poison or toxin
Some Enzymes need a cofactor or coenzyme to help them bond
Coenzymes are usually organic _______________
Cofactors are usually inorganic _______________
Many metabolic disorders are due to a lack of enzymes.
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Unit 3 Guided Notes
Cell Energy and ATP
Chemical bonds are broken to get the energy that is stored in them.
When a reaction releases energy it is called:
When a reaction takes in more energy than it releases it is called:
In a reaction, when an atom loses an electron it is called:
In a reaction, when an atom gains an electron it is called:
Usually chemical reactions are paired or grouped in a cell.
A series of linked reactions is called a ______________________________
Often times the sum of these reactions is referred to as the cell’s:
When the cell regulates its chemical reactions, it maintains its internal
equilibrium. This is called ____________________
The energy needed for metabolic reactions is transported around the cell in
the molecule ATP, or ______________________________
ATP is a ____________________, with Ribose as its sugar and ____________________ as
its nitrogenous base. It has _______________ phosphate functional groups.
The energy is carried between the _______________ and _______________
phosphate groups.
Once the energy in ATP is used, it becomes _______________
Draw the cycling reaction of ATP:
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Unit 3 Guided Notes
Photosynthesis
Photosynthesis uses the energy of ____________________ to make __________
and is the most important chemical process on earth. Organisms that
perform photosynthesis are called:
Light is made of particles called ____________________ that move in waves.
The peaks of the waves are measured in wavelengths and different
wavelengths of light carry different amounts of _______________
Sunlight is ____________________ light or white light. It is actually many
wavelengths together, which can be broken up into different _______________
Each color has a different wavelength, and therefore a different amount of:
The pigments in the plant capture most of this energy.
The most common pigment is ____________________, which absorbs all colors
except _______________. There are actually 2 types, chlorophyll _______________
Chlorophyll a absorbs more red and is the primary pigment
Chlorophyll b absorbs more blue and is an accessory pigment
The _________________ absorb more of the blue range and reflect the oranges.
The formula for photosynthesis is:
___________+ ___________+ ___________ ___________+ ___________ (+ __________)
The Eukaryotic organelle that performs photosynthesis is the:
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Unit 3 Guided Notes
Photosynthesis – Light Dependent Reactions – first part (p. 114 in textbook)
The pigments are embedded into the _________________________ membrane,
which is the __________ membrane of the chloroplast, folded into disks.
The pigments are in clusters called ____________________. There are _____ kinds.
Light hits Photosystem II and is absorbed by the Hydrogen atoms in the
pigments. The energy goes to the electrons, exciting them and splitting them
from the rest of the atom. The Hydrogen atom is now one Hydrogen ion (a
proton) (H+) and one electron (e-). The pigments become oxidized. The electrons
are picked up by the Electron Acceptor. The Electron Acceptor becomes reduced.
The Electron Acceptor donates the electrons to the Electron Transport Chain –
protein enzymes embedded in the membrane. The electrons move down the ETC
and lose their energy to the molecules of the ETC – it is used to make ATP.
Light also hits Photosystem I, exciting those electrons, which split from the
Hydrogen atom and leave the pigments. They get picked up by the Electron
Acceptor. Next to this Electron Acceptor is an enzyme that brings together the
electron, the rest of the Hydrogen Ion, and NADP+. NADP+ is an electron carrier
and takes the electron (and the H+) and becomes NADPH.
NADPH takes all the electrons from the pigments and will donate them to the
next step of photosynthesis. To replace these electrons, water is split by
Photosystem II in a process called photolysis.
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Unit 3 Guided Notes
Photosynthesis – Light Independent Reactions – second part (p. 116 in textbook)
Also called the Calvin Cycle or Dark Reactions
Need the products from the light reactions __________ and __________
Also need __________, which comes in through the stomata
Takes place in the _______________ of the chloroplast
One cycle makes 1 G3P, 2 cycles make 2 G3P, which then bond to make:
Cellular Respiration
Cellular Respiration is the process of breaking down food molecules
(specifically ____________________) in order to make _______________
The formula for cellular respiration is:
___________+___________ ___________+ ___________ (+ ___________)
All organisms perform at least some steps of cellular respiration, even
plants, this is why plants do ____________________, and why you can seal them
in a terrarium. Organisms that perform cellular respiration and get their
food from other organisms are called:
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Unit 3 Guided Notes
There are 3 parts to cellular respiration:
Glycolysis, Citric Acid Cycle, Electron Transport Chain
Glycolysis: “splitting of sugar”
Occurs in the:
______________________________ do it
It is considered an ______________
process because it doesn’t need
oxygen.
The ATP that is made is not made in
the mitochondria, so the process is
different and is called
Substrate Level Phosphorylation
The product of glycolysis is:
The net gain of ATP is:
The electron carriers are:
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Unit 3 Guided Notes
If cells are _________________ they live in an oxygen atmosphere and can continue
on with the Citric Acid Cycle and Electron Transport Chain of respiration.
Aerobic cells need oxygen and the ____________________ to continue
Before the Citric Acid Cycle, Pyruvate must be modified into:
This happens as the Pyruvate diffuses into the matrix of the mitochondria
through a protein (facilitated diffusion!).
Citric Acid Cycle (also called Kreb’s Cycle, Tricarboxylic Acid Cycle/TCA)
Takes place in the _______________ of the mitochondria and twice for each
glucose.
The products of the Citric Acid Cycle are:
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Unit 3 Guided Notes
Electron Transport Chain: occurs on the _______________ of the mitochondria
Must have __________ and __________ from Glycolysis & the Citric Acid Cycle
NADH and FADH2 lose their hydrogens. The hydrogen is split into
hydrogen ions/the proton in the nucleus (H+) and electrons (e-). The
electrons are picked up by the ETC. The electrons move down the ETC and
lose their energy to the molecules of the ETC. The molecules of the ETC are
actually protein pumps that pump the hydrogen ions across the membrane.
They hold them in the inner membrane space, keeping them from diffusing
back across. This creates a potential energy gradient. At the end of the
ETC is a protein called ATP Synthase. The hydrogen ions are eventually
released through this protein and they generate energy, much like a dam.
This energy is used to generate ATP. Oxygen waits at the end of the ETC to
capture the electrons and hydrogen ions and make water. This process of
making ATP is called Chemiosmosis or Chemiosmotic Phosphorylation. 1
NADH yields 3 ATP, 1 FADH2 yields 2 ATP, so 1 glucose makes 36-38 ATP.
The same thing happens on a smaller
scale in the ETC of the LDR of
photosynthesis. This is why some
formulas add water as a product – it
is the water produced in the ETC.
Some formulas even include the ATP
produced.
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Unit 3 Guided Notes
Fill in this summary graphic of Cellular Respiration
Make sure you can
compare and contrast
Photosynthesis & Respiration
and
Chloroplasts & Mitochondria
We breathe in oxygen because it is necessary to make ____________, which
we would die without. At the end of the Electron Transport Chain, the
oxygen we breathe in becomes _______________. How does it leave your
body?
After the Citric Acid Cycle, all the carbon in the food that you eat has been
turned into __________. How does it leave your body?
Fermentation
If an organism uses oxygen, it performs the electron transport chain and
____________ donates its hydrogen and becomes ___________, returning to
_______________. If there is no oxygen, there will not be any NAD for
Glycolysis and cellular respiration will stop.
Fermentation returns _______________ to _______________. This is necessary for
Glycolysis, and for Anaerobic organisms. They must perform Glycolysis and
Fermentation to survive.
Some organisms do not live in oxygen environments; they may even die in the
presence of oxygen. These organisms are called ___________________ anaerobes.
Some organisms can survive without oxygen, but prefer oxygen-rich
environments. These organisms are called _________________________ anaerobes.
Fermentation begins at the end of Glycolysis so the substrate for
fermentation is ______________________________. Since it is performed by
Prokaryotes and Eukaryotes, it takes place in the ____________________
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Unit 3 Guided Notes
Bacteria and animal cells break Pyruvic Acid down into ____________________,
in a process called __________________________ Fermentation.
In the reaction, NADH donates its _______________ and becomes NAD, which
returns to assist the Glycolysis reactions. Some _______________ is also
generated for energy. The lactic acid is used by some organisms to make
_______________.
Humans do this fermentation when we are ____________________ and run out
of oxygen. It is a short-term fix until we get more oxygen. The lactic acid
goes through Cellular Respiration and makes some __________. It can also
build up in our _______________ and cause pain and cramping.
Yeast & plants break Pyruvic Acid down into _______________ and
______________ in a process called _______________ Fermentation.
The process is the same, NADH donates its _______________ and becomes
NAD, which returns to assist the Glycolysis reactions. Some _______________
is also generated for energy. When yeast performs this fermentation, we
can get bread. The __________ makes the bread rise and the small amount of
_______________ that is made is evaporated when the bread bakes.
Other types of yeast make alcohol. So do certain plants – such as grapes.
Wine and champagne are made by alcoholic fermentation, but the plants
would prefer to perform Aerobic Respiration. So they must be bottled and
kept away from _______________, or else the alcohol will go bad.
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