Bellwork: 11/20 Put your phone up  Week 11/19-11/21 How do we get energy? How do plants get energy? What cell organelle helps with photosynthesis?

Today: Unit IV, pt I & II Notes

Materials Unit Book

This Week: Monday: Cell Energy Notes Tuesday: Internet Safety

Homework Have a good Thanksgiving 

Unit IV: Cell Energy

Part I: Cell Energy

List as many different forms of energy as you can

Can you think of any examples of energy being converted from one form to another

Energy in Living Systems

Energy Definition: ability to do work Sources of energy for biological organisms Food we eat  (chemical energy) Energy from the sun (light energy)

Food Chain!

Organisms Need Energy to Live Organisms get their energy in two different ways: Autotrophs: Organisms that make their own food (Ex. Plants) Heterotrophs: Organisms that get food from external environment (Ex. Humans)

Auto or Hetero?

In Ecosystems: Photosynthesis Cellular Respiration Performed by autotrophs Chemical Reaction: Light Energy + CO2 + H20 C6H12O6 + O2 Cellular Respiration Performed by almost all organisms Chemical Reaction: C6H12O6 + O2  CO2 + H20 + Energy

Compare the chemical reactions for photosynthesis & CR Compare the chemical reactions for photosynthesis & CR. What do you notice about the 2 reactions?

Cell Energy All living organisms must be able to produce energy from the environment Which of the cell processes, that we have talked about, uses energy? (hint, hint diffusion)

Cell Energy Active Transport!! Other examples: Uses energy to transport molecules across the membrane! Other examples: Muscles contracting during exercise, heart pumping, brain controlling your entire body, cells making new molecules (new organelles & enzymes), maintaining homeostasis!

Adenosine Triphosphate Adenosine Diphosphate ATP Adenosine Triphosphate ADP Adenosine Diphosphate

Chemical Energy in Cells ATP (Adenosine Triphosphate) Most important biological molecule that provides chemical energy to the cell

Structure of ATP Made of: Adenine base Ribose sugar 3 phosphate groups

Function of ATP Releases energy when the bond between the 2nd & 3rd phosphate is broken (ATP->ADP)

ATP ENERGY ADP

Part II: Photosynthesis

What cells use photosynthesis?

Photosynthesis Photosynthesis: process plants use to trap the sun’s energy & build carbohydrates (glucose) that store energy in the form of ATP 2 different phases: light-dependent reactions & light-independent reactions

Photosynthesis Chemical Reaction: CO2 + H20 + light C6H12O6 + O2 Reactants Products

Chemical Reaction 6CO2 + 6H2O ➜ C6H12O6 + 6O2 Glucose Carbon Dioxide Water Oxygen

Where Does Photosynthesis Occur?

Photosynthesis Photosynthesis occurs in the CHLOROPLASTS!!! CHLOROPHYLL traps the light energy from the sun

Light-Dependent Light-Dependent Reactions: convert light energy into chemical energy Produces ATP  REQUIRES LIGHT

Light-Independent Light-Independent Reactions: uses ATP to convert CO2 to glucose Produces sugar (glucose) This is called the Calvin Cycle DOES NOT REQUIRE LIGHT…Dark Reaction

Calvin Cycle Takes 6 rounds of the Calvin Cycle to form one sugar! https://www.youtube.com /watch?v=uixA8ZXx0KU

Answer ?s in Note Guide