3.2
3.3
3.4
9.1
Cell unit study guide – part 1: biomolecules, energetics, cell types
(chapters 3, 9, 7.1)
Vocabulary:
pH (and acid vs. base)
carbohydrate
lipid
protein
nucleic acid
nucleotide
amino acid
reactant vs. product
activation energy
enzyme vs. substrate
active site
homeostasis
9.1
9.2
9.3
7.1
ATP vs. ADP
photosynthesis
cellular respiration
chlorophyll
fermentation (contrast w/ cell
respiration)
cell membrane
cytoplasm
ribosome
DNA
eukaryote vs. prokaryote
nucleus
organelle
Textbook sections:
Levels in cell biology:
-- in ecology, we ordered levels from organism to biosphere – now, put these smaller
levels of study in order from smallest to largest (organism):
biomolecule
atom
organ system
organ
organism
tissue
organelle
cell
molecule
atom molecule biomolecule organelle cell tissue organ organ system organsim
3.2 – The importance of water
1. Identify and discuss 4 reasons why water is so important to life on earth
1) property: __cohesion / adhesion________ 2) property: ____ice floats_______
why important for life:
why important for life:
water can travel upwards in stems of plants
aquatic life not frozen in lakes and ponds
3) property: water dissolves many substances 4) property: Water resists temperature change
why important for life:
why important for life:
cells made up of lots of solutions
maintaining homeostasis is easier
2. Why does water have all these amazing properties? Water molecules attract each
other in weak bonds called __hydrogen_____ ___bonds_________
written by Kevin Bleier
Milton High School
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3. The pH scale ranges from _0__ to __14__
a. Where on the scale are acidic solutions?
__0______ - ___6.9______
Circle which number above represents the most strongly acidic solution
b. Where on the scale are basic solutions?
_7.1____ - __14_______
circle which number above represents the most strongly basic solution
c. Where on the scale are neutral solutions? ___7__________
3.3 – The four components of all cells in living organisms
1. There are four basic types of biomolecules that make up ALL living cells:
1) ___carbohydrates______
2) __lipids__________
3) _proteins________
4) ___nucleic acids_______
2. ALL of these biomolecules contain the element ___carbon_________
3. From our molecule building activity – anytime we put together smaller molecules to
make bigger ones, a __water______ molecule is also produced
4. What is the main function of carbohydrates in cells?
_____quick source of energy, structural support_________________________
5. One important (and small) carbohydrate to remember is __glucose__________
(note that we explore this carbohydrate’s role more in chapter 9 below)
6. What is the main function of lipids (or fats) in cells?
_________long term energy storage, insulation __________________________
(we will also see the importance of fats in the cell membrane next unit – chapter 8)
7. What are some of the MANY functions of proteins in cells?
building bigger parts, breaking down parts, moving parts, letting nutrients and food in,
letting wastes out
8. Proteins are made of lots of __amino____ __acids_______ that are put together in a
particular order – this order leads to the protein’s overall 3-D shape (and function)
(we will explore HOW proteins are built in the genetics unit – chapter 13)
9. What is the main function of nucleic acids (like DNA) in cells?
contain cell’s instructions for how to build proteins (instructions code for the order of
amino acids)
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10. Nucleic acids are built out of _nucleotides____ that combine to make a long code
(more about the code later … maybe you remember the As, Ts, Cs, and Gs)
3.4 – Chemical reactions and enzymes
1. in the made-up chemical reaction below, identify the reactants and products:
A+B
C+D
reactants:
A, B
products: C, D
2. Enzymes are one subgroup of __protein________ type biomolecules (from the 4 types
above)
3. What do enzymes do?
Speed up chemical reactions in cells
4. How do enzymes do the job you described above? Explain using the term activation
energy.
Enzymes lower the activation energy necessary for a chemical reaction to go, making the
reaction faster
5. Identify the metaphor given about enzymes and substrates – substrate molecules fit
into enzyme active sites like a __key______ fits into a ___lock________
6. How many different types of chemical reactions can one enzyme affect?__one_?????
7. Is an enzyme “used up” after it changes a substrate into a product?
Enzymes are not used up in chemical reactions, they can bind to a new substrate after
forming a product
8. What two environmental factors can cause an enzyme to lose its function?
1) temperature
2) pH
9. Why does the enzyme lose its function? What is happening to it at the molecular
level?
The enzyme loses it’s shape, and can no longer bind to the substrate
9.1 – Overview of energy production in cells
1. 1st paragraph (and ecology lab review) – why do organisms need a constant supply of
energy?
_____________________________________________________________________________
2. Review from ecology: converting sunlight energy into food energy is called
______photosynthesis__________________________
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3. Review from ecology: converting food energy into cell energy is called ____cellular
respiration _______
4. Now we learn the name of the molecule that carries energy around the cell: _ATP__
__ -- this molecule is produced when we break apart food energy (glucose)
5. Our cell “spends” this molecule to do cellular jobs (to stay alive, as described above)
… when spent, this molecule becomes ADP and needs to be recharged
Summary of the discussion above – note connection to energy flow from the ecology
unit
conversion: transferring energy from ATP to a protein
(or other chemical) (to power cell activities)
process: spending ATP (turning it into ADP)
which organisms: ALL organisms
which organisms: ALL organisms
protein
protein now has energy
(P falls off once protein
performs its task)
exiting ecosystems
heat energy
ANY conversion also releases
heat
protein
P
ATP
A–P–P-P
ADP
A–P–P
conversion: autotroph biomass  heterotroph
biomass
process: digestion
which organisms: heterorophs
P
conversion: cutting up biomass releases energy to recharge ATP
process: cellular respiration OR fermentation
which organisms: ALL organisms
conversion: sunlight  food energy (biomass)
process: photosynthesis
which organisms: autotrophs
entering ecosystems
sunlight energy
Word equation for cellular respiration:
_glucose___ + _oxygen___
(reactants)
_water_ + _carbon dioxide_ + _ATP___
(products)
respiration is actually many, many steps (not just one)
Chemical equation for cellular respiration:
_C6H12O6__ + __6 O2___
(reactants)
__6 H2O__+ __6 CO2_ + __ATP___
(products)
respiration is actually many, many steps (not just one)
6. Which product do cells keep in cellular respiration? __ATP_____
7. Which products are released into the environment? _water ___ + ____carbon dioxide_
8. What groups of living organisms do cellular respiration in their cells? _
all of them!!____
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Word equation for photosynthesis:
with _sun_ energy available
__carbon dioxide_ + __water_
_glucose__ + __oxygen_____
(reactants)
(products)
photosynthesis is actually many, many steps (not just one)
with __sun_______ energy
available
Chemical equation for photosynthesis:
__6CO2____ + __6 H2O_
(reactants)
____C6H12O6___ + __6 O2_____
(products)
photosynthesis is actually many, many steps (not just one)
9. What product do cells keep in this reaction? ____glucose_______
10. What product is released into the environment? __oxygen____
11. What group of living organisms does photosynthesis in their
cells?________autotrophs_________
9.2 – In-depth look at photosynthesis (read only p. 207, skim or skip the rest)
In class, we will look at the figures to explore three ideas:
a) photosynthesis is much more complicated than the summary equation above
b) photosynthesis involves a giant assembly line of enzymes, each one speeding up
one part of the reaction at a time
c) amazingly, all producers (including some bacteria, all algae, all plants) seem to
have this same assembly line of enzymes in their cells
The only part to know for this course – it is the _chlorophyll’s_____ molecule’s role to
actually capture sunlight energy in one of the first steps of the overall process
9.3 – In-depth look at energy production (read section, but focus on figure 15 p. 213)
Just like photosynthesis, respiration is also more complicated than the summary formula
above (and also involves a different assembly line of enzymes)
1. Cells have two options when breaking down glucose for ATP energy:
respiration or fermentation
2. Both paths use the same first step: __glycolysis________, making 2 ATP by doing
what?_____breaking apart glucose into 2 3-C sugars_________
A. If O2 is available, which path do cells take? ____respiration_________
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B. If O2 is unavailable, which path do cells take? ___fermentation_________
C. Which path above produces more ATP? _respiration_____________
7.1 – Two basic types of cells (skip p. 153, we will return there in chapter 10)
1. Summarize what cell theory says: All cells come from other cells, all organisms are
made of one or more cells, cells are the basic unit of structure and function in
organisms
2. Are there any weaknesses in its logic? (we’ll return to that problem later)
3. ALL cells have the following structures in common:
1) __cell membrane_ purpose: control what goes in and out of cells
2) _ribosome:
purpose: make proteins
3) __DNA___ purpose: code instructions on how to build a protein
4)
cytoplasm
purpose: (just liquid environment inside cells)
4. Beyond these similarities, there are two major types of cells:
__prokaryotes______ and ___eukaryotes_________
5. What group of living organisms are made of prokaryotic cells? ____bacteria_____
6. What groups of living organisms are made of eukaryotic cells? (look around at
posters)_protists___, __fungi_____, __plants__, __animals______
7. Basic differences:
a) Eukaryotes have a _membrane_____ surrounding their DNA, prokaryotes don’t
b) Eukaryotes have specialized factories for doing certain jobs called__organelles
____________, prokaryotes don’t
-- again, look at the list of 4 structures above – these are what prokaryotes and
eukaryotes both have in common