___ + ___ + ___ → ___ + ___ ___ + ___ → ___ + ___ + ___

Sunlight: The Fuel of Life
Fill in the blanks below to create the equations for photosynthesis and respiration. Draw a picture
on the line and label it underneath the line.
Photosynthesis:
___ + ___ + ___ → ___ + ___
Respiration:
___ + ___ → ___ + ___ + ___
Yeast Experiment:
Question: How does sugar concentration effect respiration in yeast?
Write your
Hypothesis:_________________________________________________
____
__________________________________________________________
_______________________________________________________________________________
_____________
Predictions:
1) I predict that the bubble height will be _____________________ in
________________________ sugar.
2) I predict the balloon circumference will be ___________________ in
________________________sugar.

Directions:
1. Make sure each test tube is labeled with the sugar solution to be added
2. Use the blue spoon to add two of ¼ teaspoon of yeast to each test tube
3. Use the dropper to add 10ml of one sugar solution to each test tube (1%, 4%, 7%, 10%,
and 13%)
4. Use the dropper to add 10ml of hot water to each test tube
5. Put a balloon over the top of each test tube
6. Put your thumb over the top and shake each test tube for 10-15 seconds
7. Measure the bubble height after 5, 10, 15 and 20 min. Record notes about the balloon at
the end of the experiment. Record your data in the following two tables.
Bubble Height:
Sugar solution 5 min 10 min 15 min 20 min
0%
0.5%
1%
4%
10%
Balloon:
Sugar solution description Circumference (if
0%
0.5%
1%
4%
10%
Visualize your results:
measurable)
Use the grid below to draw a bar graph or line graph of your bubble height results. Do not forget
to include a title and label your axes.

Answer the following questions using your results:
1. What did you observe during this experiment?
2. Which concentration of sugar resulted in the fastest or greatest rate of cellular respiration?
How do you know?
3. What results would you expect if we add a different type of sweetener such as brown sugar,
honey or splenda?
4. Is yeast a living organism? How do you know?

Elodea Observation:
1. Look closely at the elodea plants. What differences do you observe between the plants that
are under the light and the ones that are not?
2. Why do you think this difference occurred?
3. Observe the tiny bubbles. What kind of gas to they contain? How
do you know?
4. The title of this lesson is Sunlight: The fuel of Life. Explain how
sunlight fuels life on our planet.

Word Search
Find the following words below:
respiration oxygen Yarbrough life
photosynthesis glucose painter science
elodia energy peters cell
yeast sunlight chloroplast metabolism
water plants food growth
carbondioxide animals mitochondria reproduction
R A I P G B J R X A C N P L D L I I T E O E F C R G P
H A Y A R B R O U G H I W E L J S Y D G K U Y E L F P
E M Y Q O N K S Y D I O X O H O Z F A K P U O P F I Q
Q B J E W R B I S B E P R T U E L O D I A V Z T W B R
X C S Y T Z R A Z R B P C F M D T O S E Q N F D G J R
S G C H H I L E N E R G Y B A J S D K G L A M R R N D
O C I P W E Q T A S R Q Y G E L S Z O T M U E V H K O
W F E X G D M N Y P T Z D A H O B A Y C E T D E I J S
E A N I M A L S O I F A G H R H M I E C T J O C A K D
K D C L X E N Y L R M R E C N O U E A O A W P A Q O R
O S E T L W U T V A W S X I M P Y Y F R B Z A R A O Y
E B K E C F O D B T U E Z M F M E G S H O I O B J L T
K E V R N L O V E I M S R I N N A G O G L U C O S E O
P O M Q Y P H O T O S Y N T H E S I S R I S V N T M U
E S V Y W L X X Y N Z T A O A N T B G O S C N D E D Y
T D L S Z A F Y G E J R H C I N V I J E M H K I I L V
R F L N U N N G H A I O L H P S R Q D R R V D O S C I
S I U D V T W E N X A Y B O Z E A R B L W A C X D N W
P E M T F S G N H F K U L N I P W B H P L A J I K E L
M G E U A G P W R E P R O D U C T I O N N W T D O O S
P X Q T W R T S S G L T C R U G V Y W M S Q B E X U Y
Z H T A B H L B C C L V R I D Q X C I S E I T F R G C
L H S U N L I G H T I E J A K I C L I M O N U O P A Q
R L N V C I F S C H A T D J N U E X V N T X C W E T X
Y I Z N A A E B E C I T G O D R L E J C M F L G L H X
A I O H J J Q N G K M D L K C H L O R O P L A S T C N