Download 2.2 READING answers

Lesson 2.2 Cellular Respiration
Reading 1 What Happens During Cellular Respiration (pgs 50-53)
Getting Energy – use the picture below to answer the 2 questions
1. Infer – color in the last three energy scales to show how the
hiker’s energy changes
Low
High Low
High Low
High Low
High
2. How do you think the hiker’s breathing rate changes as she
climbs? It is faster as she climbs and slower when she rests.
Summarize Cellular Respiration
releases
Energy
from
Food
uses
Oxygen
you get from
Breathing
Cellular Respiration Equation
C6H12O6
glucose
+ 6 O2
oxygen
6 CO2 +
carbon
dioxide
6 H 2O +
water
ENERGY
Figure 2 Releasing Energy
Stage 1. In the cytoplasm, glucose is broken down into smaller molecules,
releasing a small amount of energy.
Stage 2. In the mitochondria, the smaller molecules react, producing
carbon dioxide, water and large amounts of energy.
Comparing Two Energy Processes
Energy
Photosynthesis
(green plant)
Glucose
+
Oxygen
Water
+
Carbon dioxide
Energy
(bunny + plant)
Cellular Respiration
Assess Your Understanding
1a. How does Stage 2 of cellular respiration benefit a cell?
Stage 2 releases a LARGE amount of energy that the cell can use.
1b. Why does cellular respiration add carbon dioxide to the atmosphere,
but photosynthesis does not?
Cellular respiration gives off carbon dioxide; photosynthesis uses
carbon dioxide to make glucose.
I get it! Now I know that during cellular respiration, cells break down
food, using oxygen and releasing energy.
I need extra help with…
Reading 2 What Happens During Fermentation (pgs 54-55)
Apply It
1. How does the fermentation that causes dough to rise differ from
fermentation in muscles?
Fermentation in dough produces carbon dioxide and alcohol.
Fermentation in muscles produces lactic acid.
2. How would you show that yeast was responsible for making the
dough rise?
Mix the dough with all the same ingredients, but leave out the yeast.
Energy for Life
Producers
 Plant cells capture energy by way
of (photosynthesis,
fermentation/cellular respiration).
 Plants are autotrophs because
they make their own food.
 Plant cells release energy for cell
functions by way of
(photosynthesis,
fermentation/cellular respiration).
 Plants get this energy when oxygen
reacts with sugars made in
photosynthesis.
Consumers
 A runner on an easy jog through
the woods gets energy by way of
(photosynthesis/fermentation,
cellular respiration).
 The runner is a heterotroph
because she gets energy from food
that she eats.
 If the runner makes a long, fast
push to the finish, her muscle cells
may get energy by way of
(photosynthesis/fermentation,
cellular respiration).
 This process releases less energy
and does not use oxygen.
Assess Your Understanding
2a. When a race ends, why do you think runners continue to breath
quickly and deeply for a few minutes? To replace oxygen that was used
up by the muscle cells.
2b. How do living things get energy?
(Sample) Living things get energy from food that is either made
(autotrophs, producers) or eaten (heterotrophs, consumers). Organisms
break down food through cellular respiration, releasing energy for cell
use.