BD Biology Ch. 8/Photosynthesis

Priestley's Experiment

-burned a candle in a bell jar until it went out -placed sprig of mint in bell jar for a few days -candle could be relit and burn with mint *concluded plants released a substance necessary for burning (oxygen)

Light-dependent reactions

..., produce oxygen gas and convert ADP and NADP+ into the energy carriers ATP and NADPH

Thylakoid

A flattened membrane sac inside the chloroplast, used to convert light energy to chemical energy.

CO2 Enters the Cycle

A. 6 carbon dioxide molecules are combined with six 5-carbon molecules to produce twelve 3-carbon molecules

Photosystem II

A. Light absorbed by photosystem II is used to break up water molecules into energized electrons, hydrogen ions [H+], and oxygen

What is the difference between ATP and ADP?

ATP has three phosphate groups [which gives it more energy] while ADP has only 2

What is the role of ATP in cellular activities?

ATP is used by all types of cells as their basic energy source. [storing and releasing energy], The energy from ATP is needed for many cellular activities, including active transport across cell membranes, protein synthesis, and muscle contraction.

Energy Input

B. Energy from ATP and high-energy electrons from NADPH are used to convert twelve 3-carbon molecules into higher-energy forms

Electron Transport Chain

B. High energy electrons from Photosystem II move through the electron transport chain to Photosystem I

Photosystem I

C. Electrons released by photosystem II are energized again in photosystemI. Enzymes in the membrane use the electrons to form NADPH

6 Carbon Sugar Produced

C. two 3-carbon molecules are removed from the cycle to produce sugars, lipids, amino acids, and other compounds.

Hydrogen Ion Movement

D. The inside of the thylakoid membrane fills up with positively charged hydrogen ions. This action makes the outside of the thylakoid membrane negatively charged and the inside positively charged

5 Carbon Molecules Regenerated

D. the 10 remaining 3-carbon molecules are converted back into six 5-carbon molecules, which are used in the next cycle

ATP Formation

E. As hydrogen ions pass through ATP synthase, it converts ADP into ATP

How are ATP and glucose different?

Glucose stores more energy than ATP, is better for long-term storage

pigment

Light-Absorbing molecules used by plants to gather the sun's energy

NADP+

One of the carrier molecules that transfers high-energy electrons from chlorophyll to other molecules

heterotroph

Organisms, such as animals, that can not use the sun's energy directly,obtains energy from the foods it consumes; also called a consumer

What did the experiment's of van Helmont, Priestly, and Ingenhousz reveal about how plants grow?

That in the presence of light, plants transform carbon dioxide and water into carbohydrates, and they also release oxygen.

What is ATP and what is it composed of?

The cell's energy shuttle. ATP/adenosine triphosphate is composed of ribose (sugar), adenine (nitrogenous base), and three phosphate groups

What is the overall equation for photosynthesis?

carbon dioxide (6co2) + water (6H2O) makes glucose (C6 H12 O6) + oxygen (6O2). photosynthesis uses the energy of sunlight to convert water and carbon dioxide into high energy sugars (glucose) and oxygen. , 6 CO2 + 6 H2O -> C6 H12 O6 + 6 O2

What is the role of light and chlorophyll in photosynthesis?

chlorophyll is the pigment that absorbs red and blue and reflects green;which is why plants look green, it also captures the sun's energy and is used to complete the photosynthesis process., plants gather the sun's energy with light absorbing molecules called pigments (principal pigment is chlorophyll). Chlorophyll absorbs light very well. Because light is a form of energy, any compound that absorbs light also absorbs the energy fromthat light. when chlorophyll absorbs light, much of the energy is transferred directly to electrons in the chlorophil molecule, raising the energy levels of these electrons. These high-energy electrons make photosynthesis work

Ingenhousz' Experiment

concluded that plants only produce oxygen in the presence of light

Photosystem

in the thylakoid membranes of chloroplasts, a cluster of chlorophyll and other pigment molecules that harvest light energy for the light reactions of photosynthesis [light-dependent reactions]

heterotroph/mushroom

obtain food by decomposing other animals.

heterotroph/leopard

obtain the energy stored in autotrophs indirectly by feeding on animals that eat autotrophs

ATP releasing energy

occurs when one of the phosphates break off, forming ADP and expelling the extra phosphate

autotroph

organisms, such as plants, that can capture energy from sunlight or chemicals and use it to produce/make its own food from inorganic compounds; also called a producer

Van Helmont's Experiment

planted a seed in dry soil. watered the soil for five years. the seedling gained 75 kg, but the mass of the soil was unchanged. concluded most of the mass came from water.

Where do plants get the energy they need to produce food?

plants and some other types of organsisms are able to use light energy from the sun to produce food.

Chlorophyll

principal pigment of plants and other photosynthetic organisms; captures light energy

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 [includes "light-dependent reactions" and the "calvin cycle"

Stroma

region outside the thylakoid membranes in chloroplasts [calvin cycle]

How are ATP and glucose similar?

they are both forms of energy

The Calvin Cycle

uses ATP and NADPH from the light-dependent reactions to produce high-energy sugars