Photosynthesis Notes Biology Unit 05 Lesson 01 Chemosynthesis

Photosynthesis Notes Biology Unit 05 Lesson 01

Chemosynthesis Ü Chemosynthesis uses energy released from chemical reactions to produce food for organisms. Ü Organisms that carry out chemosynthesis are microbes (bacteria) that live far from the Sun, such as deep on the ocean floor.

Which Organisms Carry Out Photosynthesis? Ü Autotrophs such as plants and some protists

Photosynthesis Ü Photosynthesis is the cellular process in which autotrophs capture light energy and convert it to chemical energy (glucose) using carbon dioxide and water.

Equation for Photosynthesis Ü 6 CO 2 + 6 H 2 O + Light Energy C 6 H 12 O 6 + 6 O 2 Ü Carbon Dioxide + Water + Light Energy Glucose (sugar) + Oxygen

Reactants & Products of Photosynthesis REACTANTS PRODUCTS Carbon Dioxide Glucose (sugar) Water Oxygen Light Energy

Where Does Photosynthesis Occur? Ü Chloroplasts Ü Contain chlorophyll in plant cells or autotrophs

Types of Chlorophyll a absorbs indigos, blues, oranges and little red. Chlorophyll b absorbs a higher rate of blue and yellows and little orange. Both reflect green wavelengths

Light Dependent Reaction Ü Occurs in the thylakoid Ü Water is absorbed through roots. Ü Sunlight enters the chloroplast, causing H 2 O molecules to split. Ü O 2 leaves as a waste product through the stomata. Ü NADP+ picks up the H+ ions (becoming NADPH) and moves them to the stroma for the light independent reaction (Calvin cycle).

Stomata Ü Found on the under side of the leaf. Ü Surrounded by guard cells that open and close to allow for CO 2, H 2 O and O 2 exchange Ü Close during the hottest parts of the day to prevent transpiration, evaporation from plants

Light Independent Reaction – Calvin Cycle Ü Carbon dioxide from the atmosphere enters Ü H+ breaks off from NADPH Ü NADP+ returns to the Light Dependent Reaction Ü Carbon dioxide becomes “fixed” with the H+ producing the glucose molecule C 6 H 12 O 6.

Reactants & Products of Photosynthesis REACTIONS PRODUCTS