Bell ringer What is the difference between autotrophs and heterotrophs?

PHOTOSYNTHESIS

What is Photosynthesis? A chemical reaction powered by sunlight that uses carbon dioxide (CO2), and water (H2O) to produce glucose and oxygen. Carbon dioxide + water Glucose + oxygen 6CO2 + 6H2O  C6H12O6 + 6O2 glucose SUN

How to read a chemical equation light energy 6CO2 + 6H2O C6H12O6 + 6O2 Inputs are on the left = reactants Outputs on the right = products (Energy is not considered a reactant so it is written above: in this reaction energy is needed to break the bonds in H2O)

Where does the plant get the CO2 and H2O? Water comes from the soil and travels in veins throughout plant including to the leaves, where photosynthesis takes place? CO2 is one of many gases in the air But how does the CO2 get into the leaf?

Through small pores called stomata or guard cells These guard cells can open and close.

Where does photosynthesis take place?

Mesophyll Cell of Leaf Photosynthesis occurs in these cells! Nucleus Cell Wall Chloroplast Central Vacuole Photosynthesis occurs in these cells!

Chloroplast Organelle where photosynthesis takes place. Stroma Outer Membrane Thylakoid Granum Inner Membrane Thylakoid stacks are connected together

How does the chloroplast work?

Chloroplasts contain chlorophyll molecules Chlorophyll is a pigment. Chlorophyll pigments harvest energy from the sun by absorbing certain wavelengths, especially blue and red. Plants are green because the green wavelength is reflected, not absorbed.

So chlorophyll is the molecule that captures the energy from the sun And turns it into energy the plant can use: ATP

Plants are autotrophs They take inorganic molecules (CO2 and H2O) and by harvesting the power of the sun, turn them into the organic molecule glucose (C6H12O6) with O2 as a byproduct. Without this ability to turn inorganic to organic molecules, life could not exist. So thank a plant today!

Bell ringer How are plants able to harness the sun’s energy, but animals are not?

Energy : from sunlight to ATP Sunlight is the ULTIMATE energy for all life on Earth Plants convert the sun’s energy into energy in the chemical bonds of sugars When those bonds are broken (in our bodies or in the plant) energy is released as ATP.

Structure of ATP ATP stands for adenosine triphosphate It is composed of the nitrogen base ADENINE, the pentose (5C) sugar RIBOSE, and three PHOSPHATE groups The LAST phosphate group is bonded with a HIGH ENERGY chemical bond This bond can be BROKEN to release ENERGY for CELLS to use

High Energy Phosphate Bond

Bell ringer What are the reactants for photosynthesis? What molecule is essential for photosynthesis to take place?

Photosynthesis Has Two Parts 20

Two Parts of Photosynthesis First part: 1.Light Reaction (or Light Dependent Reaction) --Splits water into H+ and O (which is expelled as O2) --Converts energy from sun into chemical energy of ATP SUN 21

Two Parts of Photosynthesis Second part: 2. Calvin Cycle or Light Independent Reaction Uses energy (ATP) from light reaction along with the freed hydrogen and the CO2 to make sugar (glucose). 22

Overall Reaction light energy Carbon dioxide + water  Glucose + oxygen 23