Photosynthesis & Cellular Respiration Biology 2009
Jan 21, 2016
Photosynthesis & Cellular Respiration
Biology 2009
Bellwork #22-24-09
1. It is 100 years in the future and you are a research scientist. An enormous volcanic eruption has recently sent huge quantities of dust and ash into the atmosphere. Explain how this event will affect each of the following:
a. Photosynthesis
b. Plant life
c. Animal life
d. Human societies
2. Explain how photosynthesis and respiration are related within an ecosystem
Pre-Lesson Vocabulary
1. Carbohydrates – Compound composed of C1H2O1; used by living things as a source of energy
2. Glucose (p. 30) – C6H12O6 ; The smallest unit that makes up a carbohydrate; A simple sugar
3. Starch (p. 30) – A chain of glucose molecules; used by plants to store food energy
4. Chloroplast – Organelle found in green plants that is used to produce carbohydrates (food) for the plant
Vocabulary
5. Mitochondria – Organelle found in all plant and animal cells that breaks down food to create energy for that organisms
6. Atom – Smallest unit of matter that cannot be broken down by chemical means
7. Molecule – 2 or more atoms held together by covalent bonds
8. Chemical Reaction – The making and breaking of chemical bonds; written as an equation
Vocabulary
9. Producer – Organism that is able to make its own food (plant); also known as an autotroph
10. Consumer – Organism that gets its energy by eating other organisms; also known as a heterotroph
11. ATP (adenosine triphosphate) – Molecule used by cells to deliver energy for chemical reactions to take place (similar to a battery)
Energy Flow in the Living World
1. What is the ultimate source of energy for living organisms?
2. Organisms that capture energy directly from sunlight perform the process of
3. These organisms that make their own food using sunlight and are called
4. Organisms that gain their energy from eating plants or other animals for food are called
Sunlight
photosynthesis
producers or autotrophs
Consumers or heterotrophs
5. Label the following as either a producer, consumer, or decomposer.
a. Coyote -
b. Plant -
c. Deer -
6. Look at Figure 5-10 on page 84. All energy can be traced back to the sun.
Therefore, explain how a coyote gets its energy from the sun.
consumer
consumerproducer
The sun provides energy for green plants to make their own food through photosynthesis. When a deer eats a plant, it gets its energy from the carbohydrates in the plant. The coyote then eats the deer, again transferring the energy that began with the sun.
•Draw a picture tracing you and your favorite food back to the energy from the sun. Use Figure 5-10 on page 84 as a guideline.
What did you draw???
Chemistry Review1. Why is water (H2O) considered a molecule?
2. How many atoms of hydrogen and oxygen are in one molecule of H2O? ____ Hydrogen _____ Oxygen
3. Determine the number of each atom in each of the following molecules.
a. 6CO2 = CO2 + CO2 + CO2 + CO2 + CO2 + CO2 = 6 Carbon and 12 Oxygen
b. 6H2O
c. C6H12O6
d. 6O2
e. CO2(OH)3
Chemical Reactions in Living Things1. Chemical reactions within cells drive
2. What is the vocabulary term used to describe
a. starting material-
b. ending material -
3. True or False: Atoms in the reactants are rearranged to form the products.
a. Na + Cl → NaCl b. 2H2O → 2H2 + O2
c. Na + Cl + Mg → NaCl (NO NO! – Not a chemical reaction!)
4. True or False: In any chemical reaction, the total number of atoms for each element on the reactants must equal the total number of atoms for each element on the products.
all the activities associated with life
reactant
product
True
True
Chemical Reactions in Living Things
5. Chemical reactions are written in the following form
__________________ → _____________________
6. Review Figure 5-1 and answer the following question. Explain what happens when you eat a baked potato?
When you eat a potato, chemical reactions in your mouth and small intestine convert starch into glucose. Other reactions break down glucose and release energy that your body uses to do work.
Make ProductsReactants
PhotosynthesisWrite the word equation for photosynthesis. (Yes,
you need to know this!)
Write the chemical equation for photosynthesis. (Yes, you need to know this!)
Label the reactants and products in the equation above
How is sunlight used as Energy?
• Sunlight – Sunlight is a form of energy known as electromagnetic radiation. This energy travels as waves – some waves have more energy than others.
How is sunlight used as Energy?• Electromagnetic Spectrum – is made up of
all the possible electromagnetic radiation waves ranging from gamma rays (small waves, but high energy) to radio waves (large wave, but low energy)High
Energy
Low Energy
How is sunlight used as Energy?• Visible Light – The human eye can only
detect a small portion of the electromagnetic radiation emitted from sunlight. The portion we can see is called visible light.
• Have you ever heard of ROYGBIV?R O Y G B I V
Red, Orange, Yellow, Green, Blue, Indigo, Violet
How is sunlight used as Energy?
• Pigment – Molecule that absorbs different colors of light.
• Different pigments can absorb different waves of energy from the electromagnetic spectrum.
• For example, our eyes have the pigment retinal which allows us to absorb only visible light waves.
Why do we see the colors we see?
Our eyes see colors that are being reflected. Therefore, if you look at a piece of blue paper, the pigments of your eyes will absorb the red, green and yellow wavelengths of light and they will reflect the blue wavelengths of light.
Colorblindness
Colorblindness – Affects mostly males
Red green – most common type of colorblindness
ColorblindnessYellow green
Colorblindness
How is sunlight used as Energy?
• Chlorophyll – The main pigment in plants that absorbs red and blue light and reflects green light.
• Chlorophyll is found in the chloroplasts of a plant cell
PhotosynthesisWhere do plants get their reactants?
carbon dioxide –
water –
Chlorophyll –
From the air when humans exhale; it enters through the stoma of plant leaves
Precipitation; it enters through the roots of plants
Found inside the chloroplast of a plant cell
Photosynthesis
What do plants do with the products?
glucose –
oxygen –
Stored (for winter use) or used by the plant as food for energy
Exits through the stoma of plant leaves and enters the air for us to breathe
Bellwork #3 3-3-09Fill in the blank with the correct word.
1. 2 or more atoms held together by covalent bonds: _________
2. Molecule used to give cells energy: ____________
3. An autotroph is another name for a ___________
4. The organelle plants use for photosynthesis: _________
5. The starting material of a chemical reaction: ___________
6. The main pigment in plants that absorbs red and blue light and reflects green light: ___________________
7. A diagram that shows all the possible electromagnetic radiation waves from gamma rays to radio waves: __________
**More on the next slide!!
Bellwork #3 3-3-098. What is the formula for glucose? _____________
9. Determine the number of each atom in the following molecules.
a. 5N2 =
b. 3NaCl =
c. 2C12H24O12 =
d. 4Mg(OH)2=
10. Write the word equation for photosynthesis
11. Write the chemical equation for photosynthesis.
ATP, the Energy Molecule
• ATP = Adenosine Triphosphate; a molecule that supplies the cell with energy
ATP, the energy molecule
• ATP – phosphate group = ADP ; Releases energy for cells to use (like using a battery to power a flashlight)
• ADP + phosphate group = ATP; Takes in or stores energy (recharges the battery)
ATP
• Draw a diagram to show the relationship between ATP and ADP
2 Steps of Photosynthesis: Light Reactions
Oh Boy!!
2 Steps of Photosynthesis: Calvin Cycle
Do we really need to know this???Not until AP Biology…let me give you the simple version
The Steps of Photosynthesis: Simplified
1. Step One: Known as the Light Reactions (sunlight must
be present for this step to occur)
a.Energy is captured from sunlight.
b.This process occurs in plant cells within the
chloroplast organelle by the pigment called
chlorophyll.
c. Water molecules split into H+ and O2. The oxygen
goes into the air.
The Steps of Photosynthesis: Simplified
2. Step Two: Also part of the Light Reactions.
a.Sunlight energy is converted into chemical energy in
the form of adenosine triphosphate or ATP. This
process occurs in which organelle of the plant cell?
Chloroplast
The Steps of Photosynthesis: Simplified
3. Step Three: Known as the Calvin Cycle or Dark Reactions
(this step can happen with or without sunlight).
a. Chemical energy ATP is used to make carbohydrate
molecules
b.What simple carbohydrate is represented as a product in
the chemical reaction for photosynthesis
c. ATP – P = ADP and energy is released to make the
carbohydrates or food for the plant.
Glucose
This ends photosynthesis…Any Questions???
Now on to Cellular
Respiration….
Cellular Respiration
Define Cellular Respiration –
the process by which living things break down food molecules to create energy for moving, thinking, and any other activities associated with life.
Releasing Energy from Organic Molecules
1. Organisms release energy stored as carbohydrates
through a process called cellular respiration
2. True or False Only animals use the process of cellular respiration.
3. True or False Plants and animals use the process of photosynthesis. False, only
plants!!
False, so do plants!!
Cellular Respiration
Write the word equation for cellular respiration (yes you need to know this)
Write the chemical equation for cellular respiration (yes you need to know this)
Photosynthesis vs Cellular Respiration
What do you notice about the equation for photosynthesis vs. the equation for cellular respiration?
a. They are exact opposite equations;b. The reactants for photosynthesis are the products for
cellular respiration c. The products for photosynthesis are the reactants for
cellular respiration
Photosynthesis: Carbon Dioxide + Water → Glucose + Oxygen
C. Respiration: Glucose + Oxygen → Carbon Dioxide + Water
Where do living organisms get the reactants from?
Reactant Animals Plants
Glucose
Oxygen
Food they eat (consume)
Carbohydrates they produce during photosynthesis
From the air when we inhale
From the air through the
stoma
What do living organisms do with the products?
Product Animal Plant
Water
Carbon Dioxide
ATP
Use it to keep hydrated or release it as sweat
Use it for photosynthesis or release it through transpiration
Release it into the air by exhaling
Use it for photosynthesis or release it into the air through the stoma of leaves
Used for energy to drive cell activities needed to sustain life
Used for energy to drive cell activities needed to sustain life
Cellular Respiration
1. What cell organelle converts food energy
(carbohydrates) into energy the cell can use as ATP?
2. True or False? Plant cells and animal cells contain mitochondria.
3. True or False? Plant cells use the process of cellular respiration.
Mitochondria
True
True
Cellular Respiration: Step
11. Step One: Known as
Glycolysis.
a.Glucose is broken in
half and 2 ATP
molecules are
released.
Cellular Respiration: Step 22. Step Two: Known
as Krebs cycle.
a. Glucose is
completely
broken down,
more ATP is
made, and
CO2 is
released.
Cellular Respiration: Step 33. Step Three: Known as Electron Transport Chain.
a.H2O is released and lots of ATP are made. In fact,
34 more ATP are made for each glucose molecule
Why is Oxygen so Important?
1. Aerobic Respiration – cellular respiration that occurs when oxygen is present
2. Anaerobic Respiration – cellular respiration that occurs
when oxygen is NOT present
3. Fermentation – The incomplete breakdown of glucose when oxygen is NOT available