chp 10

Autotrophic

An organism capable of synthesizing its own food from inorganic substances, using light or chemical energy. Green plants, algae, and certain bacteria are autotrophs.

Oxidation

A chemical change in which a substance combines with oxygen, as when iron oxidizes, forming rust

Redox Reaction

A chemical reaction involving the transfer of one or more electrons from one reactant to another; also called oxidation-reduction reaction.

Photosystem I

A light-capturing unit in a chloroplast's thylakoid membrane or in the membrane of some prokaryotes; it has two molecules of P700 chlorophyll a at its reaction center.

Mesophyll Cells

A loosely arranged photosynthetic cell located between the bundle sheath and the leaf surface.

Photosystem II

A photosystem that contains a pair of P680 chlorophyll molecules and uses absorbed light energy to split water into protons and oxygen and to produce ATP.

C4 plants

A plant in which the Calvin cycle is preceded by reactions that incorporate CO2 into a four-carbon compound, the end product of which supplies CO2 for the Calvin cycle.

C3 plants

A plant that uses the Calvin cycle for the initial steps that incorporate CO2 into organic material, forming a three-carbon compound as the first stable intermediate.

Cyclic Electron Flow

A route of electron flow during the light reactions of photosynthesis that involves only photosystem I and that produces ATP but not NADPH or oxygen.

NADPH

An electron carrier involved in photosynthesis. Light drives electrons from chlorophyll to NADP+, forming NADPH, which provides the high-energy electrons for the reduction of carbon dioxide to sugar in the Calvin cycle.

Plants that have the ability to avoid photorespiration are ___________________ and ___________________.

C4 & CAM

Chlorophyll

Green pigment in plants that absorbs light energy used to carry out photosynthesis

ATP Synthase

Large protein that uses energy from H+ ions to bind ADP and a phosphate group together to produce ATP

Heterotrophic

Organisms that obtain their nutrients or food from consuming other organisms.

Oxygen (O2)

Oxygen molecules are produced through photosynthesis and are utilized in cellular respiration.

Photorespiration

Reaction in which rubisco attaches oxygen instead of carbon dioxide to ribulose bisphosphate

G3P (glyceraldehyde-3-phosphate) (C3H6O3)

Significant metabolite in both the glycolytic pathway and the Calvin cycle; G3P is oxidized during glycolysis and reduced during the Calvin cycle.

Stomata

Small openings on the underside of a leaf through which oxygen and carbon dioxide can move

grana (granum)

Stacks of thalylakoids embedded in the stroma of a chloroplast

Light reactions

The first of two major stages in photosynthesis (preceding the Calvin cycle). These reactions, which occur on the thylakoid membranes of the chloroplast or on membranes of certain prokaryotes, convert solar energy to the chemical energy of ATP and NADPH, releasing oxygen in the process.

Stroma

The fluid of the chloroplast surrounding the thylakoid membrane; involved in the synthesis of organic molecules from carbon dioxide and water.

Carbon Fixation

The initial incorporation of carbon from CO2 into an organic compound by an autotrophic organism (a plant, another photosynthetic organism, or a chemoautotrophic prokaryote).

Rubisco

The most abundant protein on earth. Performs Carbon Fixation in the Calvin Cycle.

Thylakoid Membrane

The photosynthetic membrane within a chloroplast that contains light gathering pigment molecules and electron transport chains.

Carotenoid

a class of pigments that are present in the thylakoid membrane of plants and that aid in photosynthesis

Reaction Center Complex

an organized association of proteins holding a special pair of chlorophyll a molecules

Organisms that use sunlight to power the production of carbohydrates, essentially feeding themselves, are known as producers or __________________________________________.

autotroph

Any process of incorporating CO2 into larger carbon-based compounds is _____________________.

carbon fixation

Two pigments in plants that absorb some visible light are called ________________________________ and ____________________________. They are found specifically in the _______________________________.

chlorophyll a and chlorophyll b: thylakoid membranes

The organelle responsible for photosynthesis is ________________________________________.

chroloplasts

Light-harvesting Complex

complex that passes energy from sunlight to the reaction center in each photosystem; it consists of multiple antenna proteins that contain a mixture of 300-400 chlorophyll a and b molecules as well as other pigments like carotenoids

The range of radiation produced by the sun is called the ______________________________.

elctromagentic spectrum

Visible Light

electromagnetic waves that are visible to the human eye

True or False; 3-Carbon sugar (G3P) is only produced by C3 plants. ________

false

True or False; C4 and CAM plants do not use the Calvin cycle to produce sugar. ________

false

True or False; Chlorophyll is located in the stroma of chloroplasts. ________

false

True or False; NADPH is produced during linear and cyclic electron flow in the photosystems. ________

false

True or False; Oxygen (O2) is produced during linear and cyclic electron flow. ________

false

True or False; Photorespiration uses CO2 to produce 1 ATP. ________

false

True or False; Photosynthesis is a catabolic pathway. ________

false

True or False; Photosynthesis produces sugar during the light reactions. ________

false

True or False; Reduction simply means a loss in electrons. ________

false

True or False; Rubisco is always required to add a CO2 to a 5-carbon molecule. ________

false

True or False; Since plants have chloroplasts, they do not need mitochondria. ________

false

Reduction

gain of electrons

Carbon Dioxide (CO2)

gas produced by body cells when oxygen and carbon atoms from food combine; exhaled through the lungs

Calvin Cycle

light-independent reactions of photosynthesis in which energy from ATP and NADPH is used to build high-energy compounds such as sugar

_____________________________ cells are responsible for photosynthesis and are packed full of chloroplasts.

mesophyll cells

Adenosine Triphosphate (ATP)

one of the principal chemical compounds that living things use to store and release energy

Chloroplast

organelle found in cells of plants and some other organisms that captures the energy from sunlight and converts it into chemical energy

Photoautotrophic

organism that uses energy from sunlight to convert carbon dioxide and water to carbon compounds

Oxygen is produced during the process of _______________________,and the location of this process is the _______________________.

photosynthesis: chloroplast

CAM plants

plants close their stomata during the day, collect CO2 at night, and store the CO2 in the form of acids until it is needed during the day for photosynthesis

Photosynthesis

process by which plants and some other organisms use light energy to convert water and carbon dioxide into oxygen and high-energy carbohydrates such as sugars and starches

RuBP

ribulose biphosphate; a five-carbon carbohydrate that combines with CO2 to form two molecules of PGA in the first step of the Calvin Cylce

Electron Transport Chain

series of electron carrier proteins that shuttle high-energy electrons during ATP-generating reactions

Oxygen and Carbon dioxide leave and enter the plant through pores called _______________________.

stomata

Glucose

the form of sugar that circulates in the blood and provides the major source of energy for body tissues. When its level is low, we feel hunger.

Linear Electron Flow

the primary pathway, involves both photosystems and produces ATP and NADPH using light energy

Electromagnetic spectrum

the range of wavelengths or frequencies over which electromagnetic radiation extends.

True or False; C3 and C4 plants have more photorespiration than CAM plants. ________

true

True or False; Carbon dioxide is produced during the Calvin cycle. ________

true

True or False; Linear and cyclic electron flow produces ATP. ________

true

True or False; Photorespiration increases in C3 plants when the stomata are closed. ________

true

True or False; Photosystem I and II absorb different wavelengths. ________

true

True or False; Photosystems I and II are required for both linear and cyclic electron flow. ________

true

True or False; Rubisco is the most abundant protein, (enzyme), on earth. ________

true

True or False;Chlorophyll absorbs solar energy and passes it onto electrons. ________

true

When both photosystems are used, the products are ______________, _____________, ______________.

water, nadph, atp