Photosynthesis Chapter 8. Chapter 8 study guide Review 1.Where does the energy that living things need come from (originally)? The Sun

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.


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.


13. What did Priestley discover about photosynthesis?

Priestley discovered that a plant releases oxygen during photosynthesis.


14. What did the work of Jan Ingenhousz show?

Light is necessary for plants to produce oxygen.


15. What is the photosynthesis chemical equation and description?

6CO2 + 6H2O -> C6H12O6 + 6O2

Carbon dioxide + water yields (with light)

Glucose and oxygen


16. In addition to water and carbon dioxide, what does photosynthesis require?

light and chlorophyll


17. What is a pigment?

a light absorbing molecule

18. What is a plants principal pigment?

chlorophyll


19. How many types of chlorophyll are there?

2

chlorophyll a and chlorophyll b


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


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.


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


25. When sunlight excites electrons in chlorophyll, the electrons gain what?

Energy

What do these high energy electrons require?

A special carrier


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.


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.


28. What does NADPH do?

carry high energy electrons produced by light absorption in chlorophyll to chemical reactions elsewhere in the cell


29. The light dependent reactions uses energy from ___.

Light to produce ATP and NADPH.


30. The light dependent reactions produce ____ and convert ______ into the energy carriers _____.

Oxygen gas

ADP and NADP+

ATP and NADPH


31. When does photosynthesis begin?

When pigments in photosystem II absorb light


32. Why is the first photosystem called photosystem II?

It was discovered after photosystem I.


33. What carriers the high energy electrons from photosystem II to photosystem I?

the electron transport chain


34. Is NADPH created in photosystem II or photosystem I?

Photosystem I


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.


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


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.


38. The Calvin Cycle is also known as what?

the light independent reactions


39. The Calvin Cycle uses

ATP and NADPH

From the light dependent reactions to produce

high energy sugars.


40. The Calvin Cycle uses

6

molecules of carbon dioxide to produce a single

6 carbon sugar molecule


41. What does the Calvin Cycle remove from the atmosphere?

carbon dioxide


42. Name 3 factors that affect photosynthesis and describe how:

* Availability of Water – shortage of water can slow/ stop 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.


42 continued

* Intensity of Light- Increasing light can increase photosynthesis

EXIT TICKET

1.Which of the following is an autotroph? a. Mushroom b. Leopardc. Impalad. 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

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Photosynthesis Chapter 8. Chapter 8 study guide Review 1.Where does the energy that living things need come from (originally)? The Sun