Download Regents Review: Photosynthesis and Respiration

Regents Review: Photosynthesis and Respiration
Define the following terms: SEE YOUR GLOSSARY IN YOUR REVIEW BOOK
ATP –
Cellular Respiration –
Chloroplast –
Gas Exchange –
Glucose –
Guard Cells –
Homeostasis –
Mitochondria –
Photosynthesis –
Respiration –
What are the basic needs for plant growth?
Carbon Dioxide (CO2), Water (H20), Light
Photosynthesis is the conversion of light energy into chemical energy
What is the difference between autotrophic nutrition and heterotrophic nutrition?
Autotrophs can make their own food (energy)
Heterotrophs need to eat food to obtain energy
What are the two types of autotrophs?
Photoautotrophs - use light energy to make food (ex. Green plants, algae)
Chemoautotrophs - use inorganic chemicals to make food (Ex. mostly bacteria)
What are the photosynthetic pigments? Which is the most abundant?
Chlorophyll a & b (green) – most abundant
Carotenes (orange)
Xanthophylls (yellow)
What process is associated with a chloroplast? What is a chloroplast made of?
Photosynthesis. Contains: photosynthetic membranes arranged in flattened sacs called thylakoids,
stacks of thylakoids are called grana, regions between the grana are known as stroma
Why cant we just use chlorophyll alone to produce glucose? What else do we need?
It only absorbs certain amounts of light energy so we need multiple pigments. Also, it doesn’t
convert this absorbed energy into chemical energy alone, we need the proteins in the thylakoid
membranes.
Describe how guard cells regulate homeostasis within the stomates:
Regulate the opening and closing of stomates (caused by osmosis with in the two guard cells).
They are closed when little water is available, at low temperatures or when little light available
and will open when the leaf needs to release extra water, at high temperatures or when there is
enough light available.
What is the overall chemical formula for photosynthesis?
(light)
6 CO2 + 12 H2O  C6H12O6 + 6 O2 + 6 H2O
Carbon dioxide + water + light  Glucose + oxygen + water
Label the layers of a leaf cross-section below? What does each layer do/contain?
1. Outermost layer is a clear waxy cuticle that protects inner tissues and slows down water loss
from leaf
2. Epidermis is below cuticle, contains no pigment, protects inner tissues, contains stomates
(small openings on the underside of the leaf that allow the exchange of carbon dioxide, oxygen
and water vapor between the leaf and the environment)
3. Palisade mesophyll is a tightly packed 1-2 cell thick layer filled with chloroplasts, site of
photosynthesis
4. Spongy mesophyll has irregularly shaped cells and large air spaces in between cells (stomates
located near this layer to allow for gas exchange) with fewer chloroplasts found here
5. Vein contains xylem (to transport water/mineral) and phloem (to transport food/materials)
What is the difference between the light and dark
reactions?
Light dependent reactions produce ATP that the lightindependent reactions use to make glucose
What is Chemiosmosis?
Movement of H+ ions through ATP synthase proteins
within the thylakoid membrane to take ADP + P 
ATP (to produce energy for the cells to use)
Photosynthesis converts inorganic materials (H2O, CO2, light) into organic molecules (C6H12O6)
What factors affect photosynthesis:
Light intensity, temperature, water availability, mineral availability, pH, CO2 availability
What does cellular respiration break down to form energy?
Energy (e-) is released from the breakdown of glucose and used to combine ADP + P to form
ATP
Where do organisms obtain the raw materials needed?
From the food they digest (heterotrophs) or create themselves (autotrophs)
Does it occur in autotrophs and heterotrophs?
Yes in both
What organelle is associated with cellular respiration?
Mitochondria
What process transfers energy from one molecule to another?
Electron transport chain
Is the high-energy molecule ATP or ADP?
What are the two types of cellular respiration? Anaerobic and aerobic respiration. Which requires
oxygen? Aerobic. Which produces the most energy by the complete breakdown of glucose?
Aerobic.
What is glucose broken down into?
Two pyruvic acids
Describe the process of glycolysis? Does it occur in both types of respiration? How much energy
is produced?
Splitting of glucose (6-carbons) into two pyruvic acid molecules (3-carbons) which occurs in the
cytoplasm. Occurs in both types and produces 4 ATP total for each glucose molecule.
Describe fermentation and what are the end products of fermentation in yeast and bacteria?
Pyruvic acid is changed into other compounds. In yeast it makes ethyl alcohol and carbon
dioxide. In bacteria it makes lactic acid.
Where does pyruvic acid breakdown?
Within the mitochondria on the surface of the inside membrane
What is the net overall output for each glucose molecule in the Kreb’s cycle?
For each glucose molecule, it takes two turns of the Kreb’s cycle, producing 1 ATP for each cycle
producing a total of 2 ATP for each glucose molecule
How many ATP molecules does the electron transport chain produce? Where does this occur?
Produces 32 ATP for each glucose molecule. Occurs within the mitochondria across the inner
membrane.
What is the overall net reaction of cellular respiration?
C6H12O6 + 6 H2O + 6 O2  6 CO2 + 12 H2O + 36 ATP
Glucose + Water + Oxygen  Carbon Dioxide + Water + Energy
Why does muscle fatigue happen in our bodies?
During prolonged periods of physical activity, the muscle cells use oxygen faster than it can be
supplied (shuts down Krebs cycle). Muscles then continue to release energy by glycolysis.
Pyruvic acid is converted to lactic acid which can build up causing muscle fatigue
Can other organic molecules be used, like proteins or fats? Yes
Regents Review Questions
1. All life depends on the availability of
usable energy. This energy is released when
(1) organisms convert solar energy into the
chemical energy found in food
molecules
(2) respiration occurs in the cells of
producers and high-energy molecules
enter the atmosphere
(3) cells carry out the process of
respiration
(4) animal cells synthesize starch and
carbon dioxide
2. The rate at which all organisms obtain,
transform, and transport materials depends
on an immediate supply of
(1) ATP and enzymes
(2) solar energy and carbon dioxide
(3) carbon dioxide and enzymes
(4) ATP and solar energy
3. A five-year study was carried out on a
population of algae in a lake. The study
found that the algae population was steadily
decreasing in size. Over the five-year period
this decrease most likely led to
(1) a decrease in the amount of nitrogen
released into the atmosphere
(2) an increase in the amount of oxygen
present in the lake
(3) an increase in the amount of water
vapor present in the atmosphere
(4) a decrease in the amount of oxygen
released into the lake
4. The diagram below represents a
biological process.
Which set of molecules is best represented
by letters A and B?
(1) A: oxygen and water
B: glucose
(2) A: glucose
B: carbon dioxide and water
(3) A: carbon dioxide and water
B: glucose
(4) A: glucose
B: oxygen and water
6. The graph below shows photosynthetic
activity in an ecosystem over a 24-hour
period.
Data for a study on respiration in this
ecosystem should be collected during
(1) interval A, from only the producers in
the ecosystem
(2) intervals A and B, from only the
consumers in the ecosystem
(3) intervals A and B, from both the
producers and consumers in the
ecosystem
(4) interval A only, from abiotic but not
biotic components of the ecosystem
7. A student studied the location of singlecelled photosynthetic organisms in a lake for
a period of several weeks. The depth at
which these organisms were found at
different times of the day varied greatly.
Some of the data collected are shown in the
table below.
5. The diagram below represents a cross
section of part of a leaf.
Which life functions are directly regulated
through feedback mechanisms associated
with the actions of the structures labeled X?
(1) excretion and immunity
(2) digestion and coordination
(3) circulation and reproduction
(4) respiration and photosynthesis
A valid inference based on these data is that
(1) most photosynthetic organisms live
below a depth of 150 centimeters
(2) oxygen production increases as
photosynthetic organisms move deeper in
the lake
(3) photosynthetic organisms respond to
changing light levels
(4) photosynthetic organisms move up and
down to increase their rate of carbon
dioxide production
8. The relative amount of oxygen in the atmosphere of Earth over millions of years is shown in
the graph below.
At what point in the history of Earth did autotrophs most likely first appear?
(1) 3500 million years ago
(3) 1500 million years ago
(2) 2500 million years ago
(4) 500 million years ago
Untreated organic wastes were accidentally discharged into a river from a sewage treatment
plant. The graph below shows the dissolved oxygen content of water samples taken from the river
at specific distances downstream from the plant, both before, and then three days after the
discharge occurred.
9. Explain why an energy-releasing process occurring in the mitochondria of the decomposer
organisms is most likely responsible for the change indicated by the data shown at
sampling site C in the graph.
At site C oxygen is being used by the mitochondria of the decomposer to break down glucose
molecules to form ATP (energy) by the process of cellular respiration to use for the organisms
various life processes.
In recent years, the striped bass population in Chesapeake Bay has been decreasing. This is
due, in part, to events known as “fish kills,” a large die-off of fish. Fish kills occur when oxygenconsuming processes in the aquatic ecosystem require more oxygen than the plants in the
ecosystem produce, thereby reducing the amount of dissolved oxygen available to the fish. One
proposed explanation for the increased fish kills in recent years is that human activities have
increased the amount of sediment suspended in the water of Chesapeake Bay, largely due to
increased erosion into its tributary streams. The sediment acts as a filter for sunlight, which
causes a decrease in the intensity of the sunlight that reaches the aquatic plants in the Chesapeake
Bay ecosystem.
10. Identify the process carried out by organisms that uses oxygen and contributes to the fish
kills.
Cellular Respiration
11. State how a decrease in the amount of light may be responsible for fish kills in the
Chesapeake Bay area.
The decrease in the amount of light will limit the resources the plants need to convert
carbon dioxide, water and light into glucose and oxygen which is used by the fish and
other oxygen-consuming organisms within the bay. A decrease in light will limit the
production of oxygen being released through photosynthesis of the bay’s plants.