Photosynthesis
Chapter 8
Chapter 8 study guide
Review
1. Where does the energy that
living things need come
from (originally)?
The Sun
8-1 Energy and Life
2. What is an autotroph?
Include an Example.
Autotrophs make their own
food. Example: Plants
8-1 Energy and Life
3. What is a heterotroph?
Include an Example.
Heterotrophs obtain their energy
from foods they consume.
Example: Animals
Another example include
decomposers- mushrooms.
8-1 Energy and Life
4. Energy comes in many forms
including
light, heat, and electricity
And stored in
chemical compounds
8-1 Energy and Life
5. What is ATP?
Adenosine Triphosphate
One of the principal chemical
compounds that cells use to
store and release energy.
8-1 Energy and Life
6. What does ATP consist of?
Adenine, a 5 carbon sugar
Ribose, and 3 phosphate groups
8-1 Energy and Life
7. What is the difference between
ATP and ADP?
ATP has 3 phosphate groups
(triphosphate)
ADP has 2 phosphate groups
(diphosphate)
8-1 Energy and Life
8. How is the energy stored in
ATP released?
Simply by breaking the
chemical bond between the
second and third phosphates of
ATP.
8-1 Energy and Life
9. Name two ways that cells use
the energy provided by ATP:
Active transport, protein
synthesis, muscle contraction
8-1 Energy and Life
10. Between glucose and ATP,
which can store larger amounts
of energy over a longer period
of time?
Glucose stores 90x the
chemical energy of ATP.
8-2 Photosynthesis:
Overview
11. What is photosynthesis?
The process in which plants
use the high energy of sunlight
to convert water and carbon
dioxide into high energy sugar
and oxygen.
8-2 Photosynthesis:
Overview
12. What did Van Helmont
conclude through his experiment?
He concluded that most of the
gain in mass had come from water
because that was the only thing he
added.
8-2 Photosynthesis:
Overview
13. What did Priestley discover
about photosynthesis?
Priestley discovered that a
plant releases oxygen during
photosynthesis.
8-2 Photosynthesis:
Overview
14. What did the work of Jan
Ingenhousz show?
Light is necessary for plants
to produce oxygen.
8-2 Photosynthesis:
Overview
15. What is the photosynthesis
chemical equation and
description?
6CO2 + 6H2O -> C6H12O6 + 6O2
Carbon dioxide + water yields (with light)
Glucose and oxygen
8-2 Photosynthesis:
Overview
16. In addition to water and
carbon dioxide, what does
photosynthesis require?
light and chlorophyll
8-2 Photosynthesis:
Overview
17. What is a pigment?
a light absorbing molecule
18. What is a plants principal
pigment?
chlorophyll
8-2 Photosynthesis:
Overview
19. How many types of
chlorophyll are there?
2
chlorophyll a and chlorophyll b
8-2 Photosynthesis:
Overview
20. Why do plants look green?
Chlorophyll does not absorb light
well in the green region of the
visible light spectrum.
Green light is reflected by leaves,
which is why plants look green.
8-2 Photosynthesis
Overview
21. Any compound that absorbs
light also absorbs _________
from that light.
energy
8-3 Reactions of
Photosynthesis
22. Where does photosynthesis
take place?
Inside the chloroplast
8-3 Reactions of
Photosynthesis
23. Describe the structure of the chloroplast:
The chloroplasts contain
thylakoids, which are photosynthetic
membranes. Thylakoids are arranged in
stacks known as grana. Proteins in the
thylakoid membrane organize
chlorophyll and other pigments into
clusters known as photosystems. The
stroma is the space outside the
thylakoid membrane.
8-3 Reactions of
Photosynthesis
24. What are the two main
reactions of photosynthesis &
where do they take place?
• Light dependent reactions- in
the thylakoid membrane.
• Light independent (Calvin
Cycle)- in the stroma
8-3 Reactions of
Photosynthesis
25. When sunlight excites
electrons in chlorophyll, the
electrons gain what?
Energy
What do these high energy
electrons require?
A special carrier
8-3 Reactions of
Photosynthesis
26. What is a carrier molecule?
A compound that can
accept a pair of high energy
electrons and transfer them
along with most of their energy
to another molecule.
8-3 Reactions of
Photosynthesis
27. What job does NADP+
perform?
NADP+ accepts and holds 2
high energy electrons along
with a hydrogen ion (H+). This
converts NADP+ to NADPH.
8-3 Reactions of
Photosynthesis
28. What does NADPH do?
carry high energy electrons
produced by light absorption in
chlorophyll to chemical
reactions elsewhere in the cell
8-3 Reactions of
Photosynthesis
29. The light dependent
reactions uses energy from ___.
Light to produce ATP and
NADPH.
8-3 Reactions of
Photosynthesis
30. The light dependent reactions
produce ____ and convert ______
into the energy carriers _____.
Oxygen gas
ADP and NADP+
ATP and NADPH
8-3 Reactions of
Photosynthesis
31. When does photosynthesis
begin?
When pigments in
photosystem II absorb light
8-3 Reactions of
Photosynthesis
32. Why is the first photosystem
called photosystem II?
It was discovered after
photosystem I.
8-3 Reactions of
Photosynthesis
33. What carriers the high
energy electrons from
photosystem II to photosystem
I?
the electron transport chain
8-3 Reactions of
Photosynthesis
34. Is NADPH created in
photosystem II or photosystem I?
Photosystem I
8-3 Reactions of
Photosynthesis
35. Why are H+ ions important to
photosynthesis?
The inside of the thylakoid membrane
fills up with positively charged H+.
This makes the outside negatively
charged. The difference is charges
across the membrane produces the
energy to make ATP.
8-3 Reactions of
Photosynthesis
36. What protein allows H+ ions to
cross the thylakoid membrane?
ATP synthase
What else does ATP synthase do
during the light dependent reactions?
binds ADP and a phosphate
group together to produce ATP
8-3 Reactions of
Photosynthesis
37. Summarizing the light dependent
reactions- the light dependent
reactions use
water, ADP, and NADP+
And they produce
oxygen and 2 high energy
compounds ATP and NADPH.
8-3 Reactions of
Photosynthesis
38. The Calvin Cycle is also
known as what?
the light independent
reactions
8-3 Reactions of
Photosynthesis
39. The Calvin Cycle uses
ATP and NADPH
From the light dependent
reactions to produce
high energy sugars.
8-3 Reactions of
Photosynthesis
40. The Calvin Cycle uses
6
molecules of carbon dioxide to
produce a single
6 carbon sugar molecule
8-3 Reactions of
Photosynthesis
41. What does the Calvin Cycle
remove from the atmosphere?
carbon dioxide
8-3 Reactions of
Photosynthesis
42. Name 3 factors that affect
photosynthesis and describe
how:
* Availability of Water –
shortage of water can slow/ stop
photosynthesis
8-3 Reactions of
Photosynthesis
42 continued
* Temperature- above or below the
optimum range may damage
enzymes, slowing down the rate
of photosynthesis. If temperature
is too low, it may stop entirely.
8-3 Reactions of
Photosynthesis
42 continued
* Intensity of Light- Increasing light
can increase photosynthesis
EXIT TICKET
1. Which of the following is an
autotroph?
a. Mushroom
b. Leopard
c. Impala
d. Tree
EXIT TICKET
2. One of the principal chemical
compounds that living things use to
store energy is:
a. DNA
b. H2O
c. ATP
d. CO2
EXIT TICKET
3. In addition to light and
chlorophyll, photosynthesis requires
a. water and oxygen
b. water and sugars
c. oxygen and carbon dioxide
d. carbon dioxide and water
EXIT TICKET
4. The leaves of a plant appear green
because chlorophyll:
a. reflects blue light
b. absorbs blue light
c. reflects green light
d. absorbs green light
EXIT TICKET
5. The products of photosynthesis
are
a. Sugars and carbon dioxide
b. Sugars and oxygen
c. Water and carbon dioxide
d. Water and oxygen
When the bell rings…
Turn in your Exit Ticket
Be sure to study tonight for the
chapter 8 quiz TOMORROW