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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 ATP are made

2 NADH are made

2 molecules of Pyruvic Acid are made from glucose being split; each pyruvic acid molecule has 3 carbon atoms

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

The Kreb’s cycle happens 2 times – this is because there are two pyruvic acid molecules entering the Kreb’s cycle.

After both cycles, there are 6 carbon dioxide molecules, 8 NADH , 2 FADH2 , and 2 ATP molecules

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?)