PHOTOSYNTHESIS & CELLULAR RESPIRATION

Obtaining Energy Organisms are classified according to how they get energy Autotrophs – use energy from sunlight to make food Heterotrophs – must get energy from food instead of directly from sunlight

Photosynthesis 6CO2 + 6H2O → C6H12O6 + 6O2 Plants need: sunlight Water Carbon dioxide Plants make: Glucose/sugar oxygen

Photosynthesis Reactants vs. Products Carbon Dioxide Water Sunlight Glucose Oxygen

Carbon Dioxide reaches cholorplasts in the mesophyll cells by diffusing through the stomata into the leaf interior Use of fossil fuels, deforestation, and other human activities have added excess carbon dioxide to the atmosphere May enhance photosynthesis. Plants may counter-balance by developing fewer stomata

Water Less than 1% of all the water absorbed by plants is used in photosynthesis. Most of the remainder is transpired or incorporated into plant materials. If water is in short supply, stomata usually close and thus reduce the supply of carbon dioxide available for photosynthesis.

Light About 40% of the radiant energy received on earth is in the form of visible light. Leaves commonly absorb about 80% of the visible light reaching them. Light intensity varies with time of day, season, altitude, latitude, and atmospheric composition. Considerable variation in the light intensities necessary for optimal photosynthetic rates.

Location of photosynthesis In a plant In a leaf In the mesophyll In the chloroplasts Thylakoids/Grana Stacks

Why are so many photosynthetic parts green? Sunlight on a Leaf Why leaves are green. Chromatography

Factors that affect photosynthesis Light intensity Light ↑ = photosynthesis ↑ Temperature Temp ↑ = photosynthesis ↑ Carbon dioxide level CO2 ↑ = photosynthesis ↑ but then →

Cellular Respiration THIS IS NOT BREATHING!!! Cells make ATP (energy) by breaking down organic compounds (food) BOTH autotrophs & heterotrophs can do ATP is used to power all cellular activities

Cellular Respiration C6H12O6 + 6O2 → 6CO2 + 6H2O + ATP Exact opposite of photosynthesis Heterotrophs need: Food Oxygen Heterotrophs make: Carbon dioxide Water Energy

Location of Cellular Respiration In cells In mitochondria

Efficiency of respiration For every 1 molecule of glucose (sugar) 38 ATP are created!!!

BIOFLIX VIDOES ARE COOL! Photosynthesis Cellular Respiration

Other videos you can check out… Summary of Photosynthesis PS Drama in Action

Quick Quiz #1 Photosynthesis or respiration? 6CO2 + 6H2O → C6H12O6 + 6O2

Quick Quiz #2 In what organelle does photosynthesis take place?

Quick Quiz #3 In what organelle does cellular respiration take place?

Quick Quiz #4 What is ATP?

Quick Quiz #5 Use the following pictures and words to make a concept map of photosynthesis and respiration.

Now complete your TOD!!!