Download Unit 5: Cell Energy Notes

Biology Unit 4: Cellular Energy and Microscopy
Name _________________________ Hr ____
I. Cellular Energy (Photosynthesis & Respiration)
A. Energy = the ability to do ___________________. Examples of cellular energy uses include:
1. Nucleoli constructing _______________________.
2. Ribosomes building ______________________.
3. Spindle fibers moving _____________________.
4. Cells secreting substances through __________________ transport, like exocytosis.
B. Energy is stored in the ___________________ that join atoms to form molecules.
1. carbohydrates – made of C, H, & O; found as ______________ in plants, as __________________ in animals,
and as _______________ in unicellular organisms; provides ___________ - _________ energy storage.
2. lipids – made of C, H, & O; found as solid ____________ in animals and __________ in plants; provide
__________ - _______ energy storage.
3. ATP – Adenosine TriPhosphate;
 a molecule made in the ______________________
 bonds between phosphate groups can be
broken to release energy for cellular processes;
 provides ____________ - _____ - _________
energy.
 Like a fully charged battery!
ADP –
AMP -
C. Photosynthesis: Process by which all plants, some bacteria and some protists use light energy to power chemical
reactions that convert H2O and CO2 into oxygen and high-energy carbohydrates (glucose).

6 carbon dioxide molecules + 6 water molecules
reactants

1 glucose molecule + 6 oxygen molecules
 light/energy 
products
1. Major Discoveries:
a. Van Helmont’s discovery (1643) –
b. Priestley’s discovery (1771) –
c.
Ingenhousz discovery (1779) –
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2. Light
a. Part of the electromagnetic spectrum
3. Pigment – a compound that produces a color in plant or animal tissue.
a. Pigments are located in the ________________________ and ____________________ of plant cells.
b. Examples
i. Chlorophyll –
Q: From which parts of the visible light spectrum does chlorophyll absorb the most energy?
Q: From which parts of the visible light spectrum does chlorophyll absorb the least energy?
Q: What is the primary color of most plants? Explain your answer.
ii. Carotenoids –
Q: Why do the leaves of deciduous trees change color in the fall?
4. Chemical Reaction: Write the chemical name beneath each chemical formula for photosynthesis below.
6H2O + 6CO2
C6H12O6 + 6O2
5. Factors that affect photosynthesis (Text p. 214)
a.
b.
c.
D. Cellular Respiration: Process that releases energy by breaking down food molecules in the presence of O2; made up
of 3 main chemical pathways: (a) Glycolysis, (b) Kreb’s cycle, (c) the Electron Transport Chain.

6 oxygen molecules + 1 glucose molecule  6 carbon dioxide molecules + 6 water molecules + energy
reactants
 products
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Energy in our food: Photosynthesis converts solar/radiant/light energy into ____________ energy, or energy stored in the
electrons bonding sugar molecules. Short-term energy molecules (carbohydrates), and long term energy molecules (lipids),
are found in the food we eat. The energy from food that we eat is measured in calories. A calorie is the amount of energy
needed to raise the temperature of 1 gram of water 1 degree Celsius. A Calorie (w/a capital “C”) as seen on most food
labels, is also called a Kilocalorie, equal to 1000 calories (small “c”). Though cellular respiration is a complex biochemical
process, it can be simplified into 1 of 2 energy pathways, both of which take place after glycolysis. 1 pathway will be taken
if oxygen is present, the other if oxygen is not present.
Glycolysis
___________ (C6H12O6) is broken in half releasing ____ ATP’s. This occurs in the cytoplasm.
Glycolysis results in 2, 3-Carbon pyruvic acid molecules which will then enter a mitochondrion.
Anaerobic Respiration/ Fermentation
Aerobic Respiration (With Oxygen)
Path taken after glycolysis when oxygen is not available.
Path taken when oxygen is present (after glycolysis)
Very Little Energy Released. This process extracts
VERY MUCH ENERGY RELEASED.
energy without the presence of oxygen. There are 2
types, each occur in cytoplasm of different organisms:

Alcoholic Fermentation – Occurring in the
cytoplasm of yeast (a fungus) and many bacteria.
This process produces carbon dioxide (a gas
Step #2: Kreb’s/Citric Cycle – Occurs in
mitochondria after glycolysis (cytoplasm). Uses O2 to
extract more energy from the 2 halves of glucose
(pyruvic acid molecules). 2 ATP’s produced.
allowing bread to rise) and alcohol. 2 ATP’s
Step #3: Electron Transport Chain – Occurs in the
produced.
mitochondria after Kreb’s cycle. It is the aerobic
OR
cellular respiration process of extracting the

Lactic Acid Fermentation – Occurs in the
remaining energy stored in bonds of molecules
cytoplasm of all other organisms. In some fungi and
produced during the Kreb’s cycle. 32 ATP’s
bacteria, lactic acid fermentation makes cheese and
produced!!!!
yogurt. In animals (us) lactic acid fermentation
during strenuous exercise causes muscle fatigue
and soreness. 2 ATP’s produced.
Comparing Cellular Energy Processes
Cellular Process
Anaerobic Cellular Respiration
(Alcoholic Fermentation)
Reactants
Location
Energy Used or Stored
Releases 2 ATP’s
From 1 Glucose
By-Products


Releases 2 ATP’s
From 1 Glucose
Anaerobic Cellular Respiration
(Lactic Acid Fermentation)
Aerobic Cellular Respiration
(Krebs’s Cycle & Electron Transport)
2 ATP’s
32 ATP’s

Releases 2 + 32 ATP’s
From 1 Glucose




Photosynthesis
Gains 1 Glucose

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II. Nutrients
Nutrients – Substances in food that supply the energy and raw materials (molecules) an organism needs to grow, repair
itself, and maintain homeostasis. For animals (including humans) the most needed nutrients include water,
carbohydrates, lipids (fats), proteins, vitamins, and minerals.

Water – The most important nutrient, comprising 65-70% of most animals. Water maintains temperature homeostasis
because it heats up and cools down slowly (this is due to its polarity). Water also enables blood to flow through vessels
smoothly and is needed in many reactions. Metabolism is the sum of all chemical reactions in an organism.

Carbohydrates – Carbohydrates serve 2 primary functions for animals: 1) short term energy from simple sugars (fruits,
honey, & table sugar) and complex sugars/starches (potatoes, grains, & vegetables), and 2) fiber, the indigestible
cellulose (plants’ structural carbohydrates) cleans the intestines of feces.

Lipids – Lipids/fats protect/pad organs, insulate (keep body heat in), store long-term energy, are a large component of
cell membranes, and comprise some hormones (steroids).
 Saturated Fats contain only single bonds and are normally solid at room temperature (butter and other
animal fats)
 Unsaturated Fats contain at least 1 double bond between any 2 carbons and are usually liquid at room
temperature (vegetable oils).
 Polyunsaturated fats contain more than 1 double bond.
 It is recommended that our diet be <30% calories come from fats, with only 10% saturated. Health
consequences include high blood pressure, heart disease, obesity, and diabetes.

Proteins – Proteins are polymers (large molecules) made up of amino acids (small molecules). The human body can
only make 12 of the 20 amino acids needed. The 8 we cannot make are called essential amino acids and must be
obtained from our diet. Foods high in protein (meat, beans, nuts) are good sources of the essential amino acids.

Vitamins – Organic molecules that help regulate body processes, often in association with enzymes. Vitamin
deficiency may lead to dysfunction and/or death. Vitamins are found in a variety of foods & supplements (see fig. 38.6).

Minerals – Inorganic nutrients that help regulate body processes and fulfill structural needs. Minerals are found in a
variety of foods-supplements. Long-term mineral deficiency may lead to dysfunction or death (see fig. 38-7).
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III. Microscopy
Magnification – An increase in the size of an image.
Resolving/Resolution Power – How clear the magnified specimen appears.
Field of View – How much of the image is seen through ocular. 40x =
100x =
400x =
Depth of View – How resolute/clear images appear at different distances from the ocular/eyepiece.
*** Increasing the magnification will decrease resolution, field of view, and depth of view! ***
Data Table Contrasting Light vs. Electron Microscopes
Microscope Characteristics
Light Microscope
Electron Microscope
Light – Air
Electron beam – Vacuum
Colored specimen’s, stain’s, & dye’s can be
seen
No light = no color
Highest practical magnification
Radiation source & medium of travel
Radiation focusing mechanism
Specimen image
Specimen type (dead or alive)
Size & Cost
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Structures and Functions of a Common Light Microscope
 Color each microscope part by its color as indicated in the data table, below left. Be sure to color in the word
in the data table and on the picture of the light microscope, below right.
Microscope Part
Microscope Part Function
Arm & Base
(light blue, dark blue)
The 2 parts held while carrying a
scope
Ocular/Eyepiece
Holds a 10x lens for magnification
and where the specimen is viewed
(red)
Ocular Tube
(light green)
Creates a distance between ocular
lens and objective lens for correct
magnification
Revolving Nosepiece
/Objective Turret
(pink)
Moves objective lenses with
different magnifying powers to be
rotated above specimen
Objective Lens
4, 10, 40, & 100x
(dark green)
Carries the 2nd lens for
magnification
Stage w/clip
(black)
Holds slide/specimen in place for
viewing
Stage Aperture
(not seen in this view)
Hole in the stage allowing light
through
NOT ON TEST
Iris Diaphragm
(orange)
Controls light passing through
specimen
Light Source
(yellow)
Provides light needed to produce an
image
Course (Large)and
Fine (Small)
Objective Knobs
(dark & light brown)
Moves the stage up and down to
focus or improve resolution of the
image
Condenser
and Knob
Condenses/focuses light before it
passes through the specimen
NOT ON TEST
Light Intensity Knob
Regulates light intensity from the
source NOT ON TEST
(gray)
Slide Adjustment
(not seen in this view)
Moves slide/specimen (forward, left,
right, backward) w/o you touching
the slide
NOT ON TEST
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