Name _________________________ Bell _____
How Do Chloroplasts Capture Energy from the Sun?
Plant cells and some algae contain an organelle called the chloroplast. The
chloroplast allows plants to harvest energy from sunlight, a process known as
photosynthesis. Specialized pigments in the chloroplast absorb sunlight and use
this energy to combine carbon dioxide and water to make glucose and oxygen. The
complete reaction is:
6CO + 6H O
2
2
Raw Materials (Reactants)
CO = carbon dioxide
H O = water
2
2
→
C H O + 6O
6
12
6
2
Products
C H O = glucose
O = oxygen
6
12
6
2
Plant cells can use this process to manufacture glucose, a simple sugar. Some of
the glucose is used immediately for cellular respiration, where it is converted to a
high energy compound called ATP. You might recall from studies of the cell that
the process of creating ATP occurs in the mitochondria. Glucose that is not used
right away is packaged as carbohydrates or fats and then stored in the roots,
seeds, and fruits.
All autotrophs can make their own food in this way, unlike heterotrophs, which
must consume food. When you eat a potato, you are eating the carbohydrates that
the plant created from sunlight.
Sun & Energy = yellow
Photosynthesis = green
Storage Products = brown
Carbon Dioxide = red
Respiration = purple
ATP = orange
Water = light blue
Glucose = dark blue
Oxygen = pink
Name _________________________ Bell _____
The Structure of the Chloroplast
Chloroplasts are double membrane organelles with a smooth outer membrane and an
inner membrane that is folded into disc-shaped sacs called the thylakoid.
Thylakoids contain chlorophyll and other pigments (red, orange, yellow, brown) and
are found in stacks called granum (grana, plural.) These stacks are connected to
other stacks by channels called lamellae. Grana are surrounded by a gel-like
material called stroma.
Color and Label:
Outer membrane = (light green)
Thylakoids = (dark green)
Lamella = (orange)
Inner membrane = (brown)
Highlight stack of Granum = (yellow)
Stroma = (blue)
Essential Questions:
1. What two types of cells contain chloroplasts? _____________________
2. Autotrophs make their own food using energy from __________________
3. The food making process is called _______________________________
4. What are the raw materials for photosynthesis? ____________________
Name _________________________ Bell _____
5. What simple sugar is produced? ______________________________
6. What gas is used in the process? ________ What gas is released? _______
7. Where are most photosynthetic cells in plants found? _________________
8. What compound can be made from glucose and serves as long-term energy
storage? _____________________
9. Compare the raw materials of photosynthesis to the products of respiration.
10. How are these two processes (photosynthesis and respiration) related?
11. How many membranes surround a chloroplast? _______________
12. Thylakoids form stacks called __________________________________
13. Stacks of granum are connected to each other by ____________________
How Does the Mitochondria Produce Energy for the Cell?
Mitochondria are the powerhouses of the cell because they “burn” or break the
chemical bonds of glucose to release energy to do work in a cell. Remember that
this energy originally came from the sun and was stored in chemical bonds by plants
during photosynthesis.
Glucose and other carbohydrates made by plants during photosynthesis are broken
down by the process of aerobic cellular respiration (requires oxygen) in the
mitochondria of the cell. This releases energy for the cell. ATP is the energycarrying molecule produced by the mitochondria through a series of chemical
reactions. The more active a cell (such as a muscle cell), the more mitochondria it
will have.
The mitochondria are about the size of a bacterial cell and are often peanutshaped. Mitochondria have their own DNA (5) and a double membrane. The outer
membrane (2) is smooth, while the inner membrane (1) is convoluted into folds
called cristae (3) in order to increase the surface area. The matrix (4) is the
space contained within the inner membrane.
Name _________________________ Bell _____
Color and Label:
Outer Membrane = (green)
Inner Membrane = (orange)
Matrix = (blue)
DNA = (yellow)
Cristae = (red)
The Chemistry of Cellular Respiration
Shown below is the chemical equation for cellular respiration with chemical symbols
for the reactants and products of the reaction.
Color and Label:
Glucose = (purple)
Carbon Dioxide = (green)
Oxygen = (red)
Water = (blue)
A
ATP = (orange)
B
In a chemical reaction, the
A
The substances on the
side are called _______________.
B
substances are called____________.
Name _________________________ Bell _____
Essential Questions:
1. Why are mitochondria called the powerhouse of the cell? ________________
2. What types of cells would have more mitochondria than others? ___________
3. What simple sugar is broken down in the mitochondria? __________________
4. Glucose is broken down by the mitochondria by what process? _____________
5. In humans (and other animals) where does this glucose come from? _________
6. Why is this process called “aerobic?” _______________________________
7. What energy-carrying molecule is created when the chemical bonds of glucose
are broken?
8. Reactants are what go into the reaction. What are the two reactants needed
for cellular respiration to occur? (Write the chemical formula and names.)
9. Products are created during a reaction. What are the three products of
cellular respiration? (Write the chemical formula and names.)
10. What would happen if oxygen were not available?
11. Write the chemical equation for PHOTOSYNTHESIS.
12. How are photosynthesis and cellular respiration similar?