Good Afternoon!1. Reflect on the Carbon Cycle activity we

completed last class and individually complete the blank Carbon Cycle worksheet as best as you can.

• https://www.youtube.com/watch?v=JJxZH_Y5D4s

How is Carbon emitted into the atmosphere?

• Respiration

• Burning of Fossil Fuels– Coal– Oil– Natural gas

• Decomposition– When in the soil, bacteria and fungi break down

detritus (dead plant and animal life) and carbon dioxide is released into the atmosphere.

How is Carbon absorbed from the atmosphere?

• Photosynthesis• Diffusion into the surface ocean

– The surface ocean absorbs more carbon dioxide than land

– Cold water absorbs CO2 faster than warm water

• Storage in soil and deep ocean from dead and decaying plant and animal life– Carbon circulates from the surface ocean down to

the deep ocean– Detritus (dead and decaying marine life) collects in

the deep ocean where carbon can be stored for hundreds of years.

THE SUN: MAIN SOURCE OF ENERGY FOR LIFE ON EARTH

• Photosynthesis is the process by which autotrophic organisms use light energy to make sugar and oxygen gas from carbon dioxide and water

AN OVERVIEW OF PHOTOSYNTHESIS

Carbondioxide

Water Glucose Oxygengas

PHOTOSYNTHESIS

Light Energy Harvested by Plants & Other Photosynthetic Autotrophs

6 CO2 + 6 H2O + light energy → C6H12O6 + 6 O2

Food Chain

THE FOOD WEB

WHYWHY ARE ARE PLA PLANTS NTS GREGREEN? EN?

Plant Cells have Green Chloroplasts

The thylakoid membrane of the chloroplast is impregnated with photosynthetic pigments (i.e., chlorophylls, carotenoids).

• Chloroplasts absorb light energy and convert it to chemical energy

LightReflected

light

Absorbedlight

Transmittedlight

Chloroplast

THE COLOR OF LIGHT SEEN IS THE COLOR NOT ABSORBED

Chloroplasts: Sites of Photosynthesis

• Photosynthesis– Occurs in chloroplasts, organelles in certain

plants– All green plant parts have chloroplasts and carry

out photosynthesis• The leaves have the most chloroplasts• The green color comes from chlorophyll in the

chloroplasts• The pigments absorb light energy

• The location and structure of chloroplasts

LEAF CROSS SECTION MESOPHYLL CELL

LEAF

Chloroplast

Mesophyll

CHLOROPLAST Intermembrane space

Outermembrane

Innermembrane

ThylakoidcompartmentThylakoidStroma

Granum

StromaGrana

Stomata

How does Carbon get back to the Atmosphere?

Animals Eat Plants•When organisms eat plants, they take in the carbon from the plant.•Some of it becomes part of their own bodies.•Some of it will be released to the atmosphere.

How does Carbon get back to the Atmosphere?

• This process is called “Respiration!”

Equation:Food + Oxygen Carbon Dioxide + WaterC6H12O6 + O2 CO2 + H20

How does Carbon get back to the Atmosphere?

• The Goal of “Respiration” is to break down glucose and release energy for cell processes.

• Since all living organisms need this energy, all living organisms do respiration…even plants!!!

Where in the cell does Respiration take place in the cell?

• This happens in a structure in the cell called the mitochondria.