Transcript Energy

Chapter 4
Kinetic = Energy of Moving
Objects
Potential = Stored Energy
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Energy can not be created or destroyed
Energy can change forms – heat, light,
chemical, matter
A) a ball rolling down a hill
B) flowing water turning a turbine
C) a chameleon tongue catching a bug
D) a covalent bond linking phosphate
molecules
E) a pitcher throwing a baseball
A) be transferred and transformed; created or
destroyed
B) be produced and generated; moved or
relocated
C) hustle; flow
D) be increased and decreased; eliminated
E) cycle; flow
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Uses about 1% or less of energy from sun
◦ 30% is reflected back into space or
◦ 70% absorbed by Earth and converted to heat
energy
A) water.
B) sunlight.
C) sugar molecules.
D) oxygen.
E) carbohydrate molecules.
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Plants have
pigments that
can absorb light
of certain
wavelengths
Light is a form of kinetic energy
that is packets of energy called
photons moving in a wave
 Different sizes of wave produce the different
parts of electromagnetic spectrum
 Our eyes can see 740 (red) - 400 (blue) nm
 Plant pigments absorb light in different
wavelengths like our eyes
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◦ Chlorophyll a and b = absorb red/orange and
blue/violet
◦ Thus they reflect green light, which is why plants are
green
There are other plant
pigments in smaller
amounts.
In the fall, the
chlorophylls break down
first, leaving other
pigments that reflect
more orange and red
light.
A) the violet-blue portion.
B) the yellow-green portion.
C) the red-orange portion.
D) Both a) and b) are correct.
E) Both a) and c) are correct.
Built up potential
energy
When released =
kinetic energy
which can be
used to form ATP
A) in the stroma of the chloroplast
B) in the thylakoid membrane
C) in the Hobbesian membrane
D) in the cellular cytoplasm
E) around the chlorophyll molecule
A) glucose
B) Oxygen
C) Sugars
D) carbon dioxide
E) None of the above; all are products of
photosynthesis.
A) Pigments absorb light energy, which excites
electrons.
B) The energy of the sun is captured as potential
energy.
C) Water molecules split, providing a source of
electrons.
D) Only a) and c) are correct.
E) a), b), and c) are all correct.
A) oxygen and carbon dioxide diffuse out of vacuoles
when vacuole pressure is reduced.
B) thylakoids become depressurized and release nitrogen
gas.
C) oxygen is a by-product of photosynthesis.
D) the cell wall is permeable to the gases released by the
stomata.
E) due to anaerobic conditions underwater, the plant
must resort to fermentation, causing the production
of excess carbon dioxide.
A) to replace electrons that are excited by light energy
and passed from molecule to molecule down an
electron transport chain.
B) to serve as a high-energy electron carrier.
C) to concentrate the beams of light hitting a leaf,
focusing them on the reaction center.
D) to provide the protons necessary to produce
chlorophyll.
E) to replenish oxygen molecules that are lost during
photosynthesis.
A) rubisco.
B) ribulose biphosphate.
C) ATP-synthase.
D) glyceraldehyde-3-phosphate.
E) crassulacean acid.
Pleural form = stomata
A) stroma.
B) stomata.
C) grana.
D) thylakoid.
E) roots.
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Leaves have evolved
to maximize
photosynthesis
while minimizing
water loss
◦ Broad surface
oriented toward
sunlight
◦ Small stomata
regulating air intake
and transpiration
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Which is why plants
from different
ecosystem
communities can
have very different
leaves
◦ Plants compete for
sunlight, so some leaf
modifications help a
plant climb to
sunlight
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Large leaves of
tropical forest
floor plants
◦ Collect as much
light as possible
Pine trees can photosynthesize
in winter due to compounds
in sap that act as antifreeze.
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Pine trees can lose up to 26 gallons of water
on a sunny, hot day. Under dry conditions,
they lose less water than other types of trees
 1) pine needle has small surface area,
 2) leaves (needles) have a waxy cuticle layer and
 3) stomata are recessed into the needle surface, so
somewhat protected from the wind so less evaporation.
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Examine the structure of a
typical leaf and briefly
describe how each of the
following features
contributes to the leaf’s
function.
1. Interior air spaces
2. Various shapes and sizes,
but always relatively thin
3. Stomata
4. Veins
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All organisms need a form of energy
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Cell metabolism
Muscle action
Eliminating waste
Reproduction
Growth of tissues, development
Behavior
Not all use oxygen, but eukaryotes do
Overview of Process
A) oxygen is produced during metabolic activity.
B) light energy is converted into kinetic energy.
C) oxygen is used to transport chemical energy
throughout the body.
D) energy from the chemical bonds of food
molecules is captured by an organism.
E) ATP molecules are converted into water and
sugar.
Glyco = sugar
Lysis = splitting
Aerobic Respiration
1. Krebs Cycle
2. Electron transport
phosphorylation or
chain
32 ATP from 1 sugar molecule!
Total: 2 from glycolysis, 2 from Krebs
Cycle + 32 from ETC = 36 ATP net gain
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Oxygen + glucose =
Carbon dioxide + water + 36 ATP
Why we breathe
◦ Oxygen is carried to blood the transported to all
cells
◦ Waste product, carbon dioxide, diffuses to blood
and transported to lungs for release
 Interesting note: Water produced = metabolic water.
Some grain beetles live in dry grain & can exist without
ever drinking – live on metabolic water only.
A) is not performed in plants, which get their
energy solely through photosynthesis.
B) occurs in all cells.
C) is performed solely on the glucose ingested
by the organism.
D) is also referred to as the Krebs cycle.
E) completely oxidizes glucose to carbon
dioxide.
A) lactic acid; O2; acetaldehyde
B) pyruvate; ATP; NADH
C) acetyl-CoA; ADP; Pi
D) galactose; H2O; ATP
E) sucrose; lactic acid; FADH
A) the products of glycolysis are further broken down,
generating additional ATP and the high-energy electron
carrier NADH.
B) cellular respiration can continue even in the absence of
oxygen.
C) the products of glycolysis are completely converted into
ATP.
D) high-energy electron carriers pass their energy to
molecules of sugar which store them as potential
energy.
E) the products of glycolysis are further broken down,
generating additional ATP and the high-energy electron
carrier NADPH.
A) extreme sensitivity to UV light, resulting in skin
cancer at a very young age
B) fragile bones and arthritis
C) extreme muscle weakness
D) color blindness
E) inability to absorb iron, resulting in extreme
anemia
Hydrothermal vents
•First discovered by explorers of the ocean floor in the
1970’s
•Surprise discovery: vents support large community of
animals
•Too deep for photosynthesis
•What food supports animals there?
•Turns out- bacteria capable of digesting and getting
energy from the sulfides released by the vents
A) Fermentation is a less efficient energy producer
than aerobic respiration.
B) Fermentation utilizes the electrons generated in
the glycolytic breakdown of glucose.
C) Fermentation is an anaerobic process.
D) In fermentation, the molecules that are used as
final electron acceptors differ from those used
when glycolysis occurs in the presence of oxygen.
E) All of the above are correct.
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Why is energy stored in sugar molecules
rather than in ATP?
Why is long term storage in the form of lipids
and not sugars?