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Photosynthesis & Respiration

Introduction to Energy

Biochemistry

�  Why do we have to learn about chemistry in biology class?!

�  Because ALL living things are made of cells, which are made of non-living chemicals (molecules)… INCLUDING YOU!

�  Example: Calcium in bones, Iron in blood, Water in cells, Oxygen in lungs, Fluorine in your teeth… etc. (22 total)

�  CHNOPS! You’ll see this later in the notes.

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Cells Energy �  ATP – Adenosine Tri-Phosphate

�  Cell’s or the body’s energy molecule

�  There is an energy requirement in living systems

�  ATP is called Energy Currency

�  We need ATP for EVERYTHING

Animal Cells

�  We make energy using our Mitochondria

�  Mitochondria make energy though cellular energy conversion in cycles

�  Cellular Respiration

�  The release of energy takes place through the breakdown of food molecules

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Cellular Respiration

� Uses the glucose we eat and the glucose plants make, plus oxygen we breath to create up to 38 molecules of ATP – as well as the water and carbon dioxide we breath out.

Cellular Respiration

� Broken into three main parts

1.  Glycolysis: Sugar splitting phase (glucose is the sugar)

2.  Kreb’s Cycle (a.k.a. Citric Acid Cycle): Extracts the energy from glucose

3.  Electron Transport Chain: Turns the energy into ATP for the body to use

�  In total, 34 – 38 ATP is made!

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Cellular Respiration Equation C6H12O6 + 6O2 è 6CO2 + 6H2O + ATP

� Reactants are on the left of the arrow:

� Glucose

� Oxygen

� Products are on the right of the arrow:

� Carbon Dioxide

� Water

� ATP

What does this equation mean?!

�  If the equation for Carbon Dioxide is CO2, that means there is:

�  1 Carbon molecule (nothing in front of or behind the molecule means 1)

�  2 Oxygen molecules

�  Carbon and Oxygen are joined together into a compound. Since there is not a number in front of the CO2 that means there is only 1 carbon dioxide compound.

� What does the chemical formula for water mean? H2O

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Types of Cellular Respiration

� Two types of cellular Respiration

1.  Aerobic Respiration – Requires Oxygen, produces more ATP

2.  Anaerobic Respiration – Does NOT require Oxygen, makes less ATP

Photosynthesis � Photosynthesis is the ultimate source of all the

food you eat and all the oxygen you breathe

� The process in which plants make their own food (glucose) and oxygen is a byproduct

� Takes place in plant cells and other photosynthesizing organisms

�  Specific Location: Chloroplast

� Needs sun and the pigment chlorophyll

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Photosynthesis Equation 6CO2 + 6H2O + ATP è C6H12O6 + 6O2

� Reactants are on the left of the arrow: � Carbon Dioxide � Water � ATP � Chlorophyll

� Products are on the right of the arrow: � Glucose � Oxygen

Cycles � Why do plants and animals need each other?!

� They are a cycle

� What would happen to plants if all animals died (and vice versa?)