Biology

Photocynthesis Notes

Energy: The ability to perform work

Work: The ability to change or move matter against other forces.

WHAT DO CELLS NEED ENERGY FOR?

• active transport
• growth & development
• repair
• reproduction

HOW DO CELLS OBTAIN THEIR ENERGY?

Autotrophs: Cells or organisms that make their own food. Ex. plants, some protists, some prokaryotes

Heterotrophs: Cells or organisms that CAN NOT make their own food. Obtain energy by eating other organisms. Ex. animals, fungi, some protists

Note: auto. & hetero. synonymous to producer & consumer

Glucose: "the CELLULAR food"

• C(16)H(12)O(6)
• A simple monosaccharide

Cells break down glucose to make ATP

ATP: Adenosine TriPhosphate

• The energy molecule of cells
• It is the "fuel" cells use to function

Ecological Rules

• Everything is connected to everything else
• Everything must go somewhere
• Nature knows best
• There's no such thing as a free lunch

Ecological Pyramids

• Show the relationship between producers & consumers at different levels in an ecosystem
• At each level of the energy pyramid, 90% is "lost" Energy through heat, being eaten, digested & used to make ATP
• Remaining 10% energy can be transferred to the next highest trophic level

Food Chains: shows the series of steps through which energy is transferred

The sun is the ultimate source of energy for ecological pyramids-providing energy to autotrophs to produce their own food!

WHERE DOES PHOTOSYNTHESIS TAKE PLACE IN THE CELL?

In the chloroplast: green organelle containing chlorophyll in which photosynthesis occurs

Light Dependent Reaction: (light is required)

• sunlight/radiant light must be present for this to occur
• takes place in the grana "green stacks of pancakes"