Photosynthesis

Notes

Biology Unit 05 Lesson 01

Chemosynthesis

Chemosynthesis uses energy released from chemical reactions to produce food for organisms.

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?

Autotrophs such as plants and some protists

Photosynthesis

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

6CO2 + 6H2O + Light Energy C6H12O6 + 6O2

Carbon Dioxide + Water + Light Energy Glucose (sugar) + Oxygen

Reactants & Productsof Photosynthesis

REACTANTS PRODUCTS

Carbon Dioxide Glucose (sugar)

Water Oxygen

Light Energy

Where Does Photosynthesis Occur?

Chloroplasts

Contain chlorophyll in plant cells or autotrophs

Cellular respiration

What is it? the process in which organisms acquire energy

from food. (Release of chemical energy for cellular use.)

The chemical equation for respiration is: C6H12O6 + 6O2 6CO2 + 6H2O Glucose + Oxygen Carbon Dioxide + Water

Where does it occur? Starts in cytoplasm, finishes in Mitochondria, all cells

TWO parts Glycolysis, respiration/fermentation

STEP 1: GlycolysisBreaks the glucose into two 3-carbon

sugars called pyruvate

Reactants & Productsof Photosynthesis and respiration

REACTANTS PRODUCTS

Phot

Resp

Light Dependent Reaction

Occurs in the thylakoid

Water is absorbed through roots.

Sunlight enters the chloroplast, causing H2O molecules to split.

O2 leaves as a waste product through the stomata.

NADP+ picks up the H+ ions (becoming NADPH) and moves them to the stroma for the light independent reaction (Calvin cycle).

Light Independent Reaction –Calvin Cycle

Carbon dioxide from the atmosphere enters

H+ breaks off from NADPH

NADP+ returns to the Light Dependent Reaction

Carbon dioxide becomes “fixed” with the H+ producing the glucose molecule C6H12O6.