UNIT IV STUDY GUIDE

I. Vocabulary Check

______1.Loss of electrons

______2. Breakdown of glucose in the presence of oxygen to produce ATP; exergonic

______3. Electron carrier utilized in photosynthesis

______4. Folds of inner mitochondrial membrane; location of ETC

______5. Describes plants that open stomata at night to minimize water loss; incorporate CO2 into organic acids

______6. 3-carbon molecule; intermediate in glycolysis, Calvin cycle

______7. Initial breakdown of glucose; occurs in cytosol; net gain of 2 ATP

______8. Pigment molecule that absorbs light energy in red, blue portions of visible spectrum

______9. Disorder; Tendency of matter described by Second Law of Thermodynamics

______10. End product of glycolysis

______11. Chlorophyll a; reaction center of photosystem II

______12. Conversion of light energy to stored chemical energy; endergonic pathway

______13. Gain of electrons

______14. Waxy barrier that forces water through cell membrane prior to entering xylem

______15. ATP production in which phosphate group is transferred from another molecule

______16. 2-carbon enzyme complex; starting point for citric acid cycle

______17. Captures energy from “falling” electrons to createelectrochemical gradient required for ATP production

______18. ATP production using ATP synthase, oxygen as ultimate electron acceptor

______19. Region of mitochondria where citric acid cycle takes place

______20. Enzyme complex that utilizes proton motive force to phosphorylate ADP

______21. Self-feeder

______22. Protein channels abundant in cell membranes of plant root cells; facilitate water movement

______23. Electron carrier utilized in glycolysis and citric acid cycle

______24. Term used to describe production of ATP using energy provided by ETC

______25. Site of Calvin Cycle; fluid-filled space of chloroplast

______26. Chlorophyll a; reaction center of photosystem I

______27. Region of leaf in which most photosynthesis occurs

______28. Describes ATP production in light reaction of photosynthesis

______29. Pigment molecules that increase action spectrum of photosynthesis; reflect red, yellow light

______30. Pathway in photosynthesis that converts light energy to energy in the form of ATP, NADPH

______31. Anaerobic pathway; pyruvate is reduced, NADH is oxidized to continue glycolysis

______32. Split to provide electrons for reduction of P680; releases H+ and O2

______33. Enzyme that catalyzes the first step of the Calvin Cycle

______34. Electron carrier utilized only in citric acid cycle

______35. Pores in underside of leaf that allow for gas exchange

______36. Occurs in mitochondrial matrix; redox reactions produce NADH, FADH2; CO2 released as waste

______37. 5-carbon molecule; provides substrate for carbon fixation in Calvin Cycle

______38. Describes plants that fix CO2 and carry out Calvin Cycle in 2 different locations; concentrates CO2

______39. Cycle in which CO2, ATP, and NADPH are used to produce CH2O

______40. Sacs in chloroplasts; site of light reaction

______41. Enzyme used by C4, CAM plants to initially fix CO2 into organic molecule

______42. Vessel used to transport water, minerals in most plants

______43. Evaporation of water from leaves due to lower Ψ of atmosphere; pulling force for water movement

______44. Waxy coating on leaves to minimize water loss

______45. Vessel used to transport carbohydrates in most plants

______46. Membrane-lined openings that connect one plant cell to another

II. PHOTOSYNTHESIS

1. Identify each of the following structures found in a chloroplast. What role do they play in photosynthesis?

2. Chloroplasts are unique in that they contain ______and ______. For what other cell organelle is this true?

3. Provide the equation for photosynthesis. What molecule is oxidized? Reduced?

4. Is this an anabolic or catabolic reaction? Positive or negative ΔG?

5. In plants, in which part of the leaf does photosynthesis occur?

6. Explain how each of the reactants is delivered to a chloroplast.

7. Explain how the carbohydrates produced are transported to the rest of the plant.

8. Identify two other groups of organisms that carry out photosynthesis. Where does each part of the pathway occur in these groups?

AN OVERVIEW OF PHOTOSYNTHESIS

Photosynthesis consists of two pathways, the ______which occurs in the ______and the ______, which takes place in the ______of chloroplasts.

In the first pathway,light energy is converted to chemical energy in the form of ______and ______.

The first step involves Photosystem ______. Light energy packaged in ______, primarily in the ______and ______portions of the visible spectrum, is absorbed by antenna pigment molecules. The energy is passed along until it reaches the reaction center, a pair of chlorophyll ____ molecules known as ______. The chlorophyll molecules of the reaction center respond to this energy by losing 2 electrons to the primary electron acceptor. The electrons then move through an ______. As the electrons move through the ETC, energy is released and used to move ______into the ______of the ______. The electrons originally lost from the reaction center are replaced by the splitting of ______, producing ______as a waste product and additional ______ions. The accumulation of ions create an ______(also called the ______) which is used to power the enzyme complex, ______. As H + ions pass through the enzyme complex and move into the ______, an inorganic phosphate group is added to ADP, creating ______. This process is known as ______. In Photosystem ______, as light energy is captured and transferred, a pair of chlorophyll _____ molecules, known as ______, are excited, causing the loss of 2 electrons. The two excited electrons are passed through a short electron transport chain ending with the reduction of ______to ______. The electrons lost by the reaction center in this photosystem are replaced by ______.

There is an alternative pathway seen in some bacteria and plants which only utilizes photosystem _____. This is a cyclic pathway in which electrons are simply recycled. Although ______is created, there is no production of ______or ______.

The second part of photosynthesis is known as the ______. There are three phases in this cycle,

______, ______, and ______. First, ______is added to ______, abbreviated as ______. This requires the action of the enzyme, ______. The resulting intermediate splits, and using energy provided by ______, is then reduced forming ______, and oxidizing ______to ______. This is known as the ______Phase. For every _____ turns of the cycle, one molecule of ______leaves the cycle to be used in carbohydrate production. Finally, in the last phase of the Calvin Cycle, ______is regenerated, requiring additional ______.

Synthesis of glucose requires ______turns of the Calvin cycle. In addition other carbohydrates can be synthesized including ______for plant cell walls, ______for glucose storage, and the _____saccharide, sucrose (composed of ______monomers) often used for transport in the plant.

III. CELLULAR RESPIRATION

1. Identify the following structures of a mitochondrion. What is the role of each structure in cellular respiration?

2. What is the equation for cellular respiration? What is oxidized? Reduced?

3. Is the reaction anabolic or catabolic? Positive or negative ΔG? Explain.

AN OVERVIEW

The first step in cellular respiration is ______. This occurs in the ______of cells and is an ______pathway. It is divided into two phases, the ______phase and the ______phase. In the first phase, _____ ATP are required to provide the energy to split glucose into 2 ______molecules. In the 2nd phase, these molecules are oxidized, producing 2 ______, 2 ______, and ______ATP for a net gain of ______ATP.

If ______is present, the ______formed in glycolysis moves into the mitochondria. An intermediate step takes place prior to the citric acid cycle. First, a ______group is given off as ______. The remaining 2-C molecule is oxidized, reducing ______to ______. Finally, the oxidized 2-C molecule attaches to an enzyme complex to form ______.

This complex enters the citric acid cycle. A series of redox reactions take place, producing 6 ______and 2 ______,. In addition, carboxyl groups are removed, releasing ______and 2 ______are produced through ______phosphorylation. The reduced electron carriers formed in the citric acid cycle move to the electron transport chain and the electrons are “dropped” from one molecule to another, with each successive molecule more ______than the one before it. The ultimate electron acceptor is ______which is reduced to form ______. As the electrons fall, their energy is used to drive ______from the ______to the ______, creating an ______gradient. This gradient, also known as the ______force, powers the enzyme complex, ______, and ADP is phosphorylated to produce ATP. Each NADH produces approximately ______ATP and each FADH2 produces about ______ATP. There are ______NADH produced in glycolysis, _____ NADH formed in the intermediate step, and ______NADH ______FADH2formed in the citric acid cycle so there is enough electron energy to produce a total of ______ATP. The ATP produced through ______phosphorylation is added to the _____ ATP from glycolysis and the ______ATP from the citric acid cycle for a total of ______ATP produced per molecule of glucose in cellular respiration.

IV. A COMPARISON OF CELLULAR RESPIRATION & PHOTOSYNTHESIS

Characteristic / Cellular Respiration / Photosynthesis
1. Type of metabolic reaction
2. Purpose of Pathway
3. Reactants required
4. End products
5. Occurs in cells of what organisms?
6. Site(s) involved in eukaryotic cells
7. Site(s) involved in prokaryotic cells
8. Mechanism for ATP production
9. Electron Transport Carrier Involved
10. Location of ETC
11. Source of Electrons for ETC
12. Final Electron Acceptor in ETC