Objective Students will be able to verbally list the reactants and products of Photosynthesis by the end of the period.

Photosynthesis Chapter 8 Ag Biology Ms. Prescott 8-1 Energy and Life 8-2 Photosynthesis 8-3 Light-Dependent Reactions & Calvin Cycle

8-1 Energy and Life

Saving for a Rainy Day Suppose you earned extra money by having a part-time job. At first, you might be tempted to spend all of the money, but then you decide to open a bank account. 1. What are the benefits of having a bank account? 2. What do you have to do if you need some of this money? 3. What might your body do when it has more energy than it needs to carry out its activities? 4. What does your body do when it needs energy?

8-1 Vocabulary Autotroph- Heterotroph- Adenosine triphosphate (ATP) – organism that can capture energy from sunlight or chemicals and use it to produce its own food from inorganic compounds; also called a producer Heterotroph- organism that obtains energy from the foods it consumes; also called a consumer Adenosine triphosphate (ATP) – one of the principal chemical compounds that living things use to store energy.

8-1 Energy and Life 1. Autotrophs and Heterotrophs Autotrophs: organisms, like plants, that use light energy from the sun to produce their own food Because plants can “manufacture” their own energy directly, they are self-sufficient. Heterotrophs: organisms that obtain energy from foods they consume All other forms of life, such as humans, animals, insects and even bacteria, depend on other living things for sustenance.

8-1 Energy and Life 2. Chemical Energy and ATP a. The cell’s activities are powered by chemical fuels i. ATP is a compound that living things use to store energy ii. ADP is the compound used to store energy in cells It can hold one more phosphate when energy is needed Energy is released when ATP converts to ADP Adenine Ribose 3 Phosphate groups

Figure 8-3 Comparison of ADP and ATP to a Battery Section 8-1 ADP ATP Energy Energy Adenosine diphosphate (ADP) + Phosphate Adenosine triphosphate (ATP) Partially charged battery Fully charged battery Go to Section:

Figure 8-3 Comparison of ADP and ATP to a Battery Section 8-1 ADP ATP Energy Energy Adenosine diphosphate (ADP) + Phosphate Adenosine triphosphate (ATP) Partially charged battery Fully charged battery Go to Section:

8-1 Energy and Life b. ATP and Glucose a. Most cells only have a small amount of ATP, enough to last for only a few seconds of activity because it is not good for storing large amounts of energy for long periods of time Glucose stores more than 90 times the energy of a molecule of ATP Cells can regenerate ATP from ADP as needed by using the energy in carbohydrates, like glucose

8-2 / 8-3 Photosynthesis: An Overview

8-2 Interest Grabber Trapping Energy Have you ever used a solar-powered calculator? No matter where you go, as long as you have a light source, the calculator works. You never have to put batteries in it. 1. A solar-powered calculator uses solar cells that are found in rows along the top of the calculator. Into what kind of energy is the light energy converted so that the calculator works? 2. Recall that plants use light energy from the sun to make food. Into what kind of energy is the light energy converted by plants? 3. Most plants, no matter what size or shape they are, have some parts that are green. Which parts of a plant are usually green? 4. What does the green color have to do with the plant’s ability to convert light energy into the energy found in the food it makes?

8-2/8-3 Vocabulary Photosynthesis- Pigment- Chlorophyll- Thylakoid- process by which plants and some other organisms use light energy to power chemical reactions that convert water and carbon dioxide into oxygen and high-energy carbohydrates such as sugar and starches. Pigment- light-absorbing colored molecule Chlorophyll- principal pigment of plants and other photosynthetic organisms; capture light energy Thylakoid- Saclike body in chloroplasts made of photosynthetic membranes that contain photosystems.

8-2/8-3 Photosynthesis Notes 1. The Photosynthesis Equation Photosynthesis uses the energy of sunlight to convert carbon dioxide and water into high-energy sugar and oxygen 6C02 + 6H2O  C6H12O6 +602 Chemically: Green Plant 6C02 + 6H2O C6H12O6 +602 Light Energy ( Carbon dioxide + Water Sugar + Oxygen) Written: “Six molecules of carbon dioxide plus six molecules of water combine in the presence of a green plant and light energy to form one molecule of sugar and six molecules of oxygen.”

8-2/8-3 Photosynthesis 2. Light and Pigments a. In addition to water and carbon dioxide, photosynthesis requires light and chlorophyll, a molecule in chloroplasts b. Plants gather the sun’s energy with light-absorbing molecules called pigments The principal pigment is chlorophyll Energy molecules released from the reaction are ATP & NADPH

Photosynthesis: Reactants and Products Section 8-2 Light Energy Chloroplast CO2 + H2O Sugars + O2 Go to Section:

Figure 8-5 Chlorophyll Light Absorption Section 8-2 Absorption of Light by Chlorophyll a and Chlorophyll b Chlorophyll b Chlorophyll a V B G Y O R Go to Section:

8-2/8-3 Photosynthesis 3. Inside a Chloroplast a. Chloroplasts contain saclike photosynthetic membranes call thylakoids arranged in stacks b. The thylakoids contain clusters of chlorophyll and other pigments and protein known as photosystems c. There are two stages to photosynthesis used to make glucose Light-dependent reactions: take place in the thylakoid Light-independent reactions (Calvin Cycle): takes place in the stroma, outside the thylakoid

8-3 Light-Dependent Reactions & Calvin Cycle

8-3 Vocabulary Thylakoid- Stroma- saclike body in chloroplasts made of photosynthetic membranes that contain photosystems Stroma- region outside the thylakoid membranes in chloroplasts NADP+ (Nicotinamide adenine dinucleotide) – one of the carrier molecules that transfer high-energy electrons from chlorophyll to other molecules.

8-3 Vocabulary Light-dependent reaction- ATP synthase- Calvin Cycle- reactions of photosynthesis that use energy from light to produce ATP and NADPH ATP synthase- large protein that uses energy from H+ ions to bind ADP and a phosphate group together to produce ATP Calvin Cycle- reactions of photosynthesis in which energy from ATP and NADPH is used to build high-energy compounds such as sugars.

8-3 Light-dependent Reactions a. Light dependent reactions produce oxygen gas and convert ADP into energy carrier ATP Water is split to produce H+ and O2 (oxygen) Light energy is converted into chemical bond energy (ATP and NADPH)

8-3 Calvin Cycle 2. The Calvin Cycle a. The Calvin Cycle uses energy from the light-dependent reactions to make sugars b. As photosynthesis continues, the Calvin Cycle runs, producing sugars while removing carbon dioxide from the atmosphere CO2 Enters the Cycle Energy Input ChloropIast 5-Carbon Molecules Regenerated 6-Carbon Sugar Produced Sugars and other compounds

Figure 8-7 Photosynthesis: An Overview Section 8-3 Light O2 Sugars CO2 Chloroplast Chloroplast NADP+ ADP + P Light- Dependent Reactions Calvin Cycle ATP NADPH Go to Section:

Concept Map Photosynthesis Light- dependent reactions Calvin cycle Section 8-3 Photosynthesis includes Light- dependent reactions Calvin cycle takes place in uses use take place in Thylakoid membranes Stroma NADPH ATP Energy from sunlight to produce of to produce ATP NADPH O2 Chloroplasts High-energy sugars