Cellular Energy Biology

Vocabulary ATP Phosphorylation Photosynthesis Pigments

ATP All cells need __________for life. ENERGY All cells need __________for life. Some things we use energy for are: Moving Thinking Sleeping Breathing Growing Reproducing

The principal chemical compound used by living things to store energy is: adenosine triphosphate (ATP). Labeled Sketch: Adenine Ribose 3 Phosphate groups

Energy Storage/ Energy Release Adenosine diphosphate (ADP) + Phosphate Energy Adenosine triphosphate (ATP) Partially charged battery Fully charged battery Energy can be stored by adding a phosphate group to ADP, creating ATP, called phosphorylation. Breaking the phosphate chemical bond in ATP releases energy, changing the ATP back into ADP.

ATP: ATP is used for active transport, movement of cell organelles and other basic functions (mitosis, etc) Glucose: sugar molecule that stores 90 times more energy than ATP. Glucose is used to regenerate ATP.

Why do we use ATP? Why not just get energy from sugar directly? ATP is small units of energy. Sugar is a very high energy molecule (if you burn it all at once…spontaneous combustion!)

Comparison of burning a marshmallow at a campfire vs in your body. When sugar burned in fire: Both have in common (Similarities) When sugar burned in body Energy is released quickly as heat and light -Glucose and oxygen are reactants. -Carbon dioxide and water are products. -Both release energy. Energy is stored in small ATP molecules for slow use

Analogy: Power lines= sugar = tons of energy Wall socket = ATP = smaller units of energy

Photosynthesis 6CO2 + 6H2O  C6H12O6 + 6O2 Process by which plants use water, carbon dioxide, and energy from sunlight to produce sugar (and oxygen). Basic Equation 6CO2 + 6H2O  C6H12O6 + 6O2

Photosynthesis Experiments 1600’s – Van Helmont Determined that mass gained during plant growth does NOT come from the soil. He concluded it must come from the water he added. 1700’s – Preistly Determined that plants release oxygen 1700’s – Ingenhousz Building on Preistly’s work, he determined that oxygen was only produced in the presence of light.

Photosynthesis Equation in Detail Chemical Equation 6CO2 + 6H2O  C6H12O6 + 6O2 + ATP + NADPH Glucose continues to be processed into ATP. ATP utilized as energy for reactions NADPH used in later photosynthesis reactions Oxygen released for use in aerobic reactions How do plants USE these raw materials?

Light and Pigments Why are most plants green? Are there plants / photosynthetic organisms that are other colors? -Why? The answer lies in: Light Spectra Pigments

Light and Pigments What is the light spectra? Visible light is just a small part of the electromagnetic spectrum

Light and Pigments The longest wavelengths have the lowest energies. (radio) As wavelengths decrease, the energy increases. (gamma)

Light and Pigments red orange yellow green blue indigo violet. Different colors correspond to different wavelengths The colors of the rainbow are ROY G BIV: red orange yellow green blue indigo violet. red has the longest wavelength, and the lowest energy violet has the shortest wavelength, and the highest energy

Only red light is reflected Seeing color The color an object appears depends on the colors of light it reflects. For example, a red book only reflects red light: Homework White light Only red light is reflected Homework

Purple light White light A pair of purple pants would reflect purple light (and red and blue, as purple is made up of red and blue): Purple light A white hat would reflect all seven colors: Homework White light

Using colored light If we look at a colored object in colored light we see something different. Shirt looks red White light Homework Shorts look blue

In different colors of light these clothes would look different: Red light Shirt looks red Shorts look black Shirt looks black Blue light Homework Shorts look blue

Light and Pigments Plants gather light spectra with light absorbing molecules called PIGMENTS The major pigment used by plants is chlorophyll There are two main chlorophyll types a and b

But very poorly in the green part of the spectrum. Light and Pigments Chlorophyll a and b absorb light very well in the violet/blue and orange/red parts of the spectrum. But very poorly in the green part of the spectrum. This makes most plants green (remember, to see a color it needs to be reflected)

Light and Pigments Beta-carotene (orange) Other pigments are also present in plants that use other wavelengths These include: Beta-carotene (orange) Xanthophyll (Lutein) (yellow)

There is so much chlorophyll, it masks other pigment colors. Light and Pigments Autumn Leaves There is so much chlorophyll, it masks other pigment colors. Light regulates chlorophyll production, so shorter days means less chlorophyll is produced, and the green color fades. Anthocynanins, producing red color, are produced during the breakdown of chlorophyll.

Photosynthesis And the Calvin Cycle Biology

Vocabulary Granum Photophosphorylation Stroma Thylakoid

(AKA The Dark Reaction) Overview of Reactions 1) The Light Reaction Reactants H2O Light NADP+ ADP + P Products ATP NADPH O2 2) The Calvin Cycle (AKA The Dark Reaction) CO2 ATP NADPH Sugar NADP+ ADP + P

Location of Reactions Thylakoid: Sac-like photosynthetic membranes, location of the light reaction Granum: A collection or stack of thylakoids Stroma: Gel-like space outside the thylakoid, location of the Calvin Cycle

Location of Reactions Chloroplast Water O2 Sugars CO2 Stroma Thylakoid NADP+ ADP + P Light- Dependent Reactions Calvin Cycle ATP NADPH Stroma Thylakoid

Photophosphorylation Definition: Using light energy to phosphorylate ADP to make ATP A way to hold energy.

What is NADPH / NADP+ ? NADPH is a co-enzyme that is an electron carrier. It exists in two forms: NADPH has the electron NADP+ lacks the electron

Two Sets of Reactions Light dependent reactions: use light to store energy in carrier molecules (ATP, NADPH)

Photosynthesis Light Reaction 1) What is water needed for? Used in the light reaction when sunlight is present Water O2 Sugars CO2 Chloroplast Chloroplast NADP+ ADP + P Light- Dependent Reactions Calvin Cycle Animation ATP NADPH

Photosynthesis Light Reaction 2) What product is released at the end of the light reaction? Oxygen Water O2 Sugars CO2 Chloroplast Chloroplast NADP+ ADP + P Light- Dependent Reactions Calvin Cycle ATP NADPH

Photosynthesis Light Reaction 3) What two high energy molecules are produced by the light reaction Water O2 Sugars CO2 ATP & NADPH Chloroplast Chloroplast NADP+ ADP + P Light- Dependent Reactions Calvin Cycle ATP NADPH

Two Sets of Reactions Light independent reactions (Calvin Cycle): Uses energy from light dependent reactions to produce sugars

Photosynthesis Light Reaction 4) What is carbon dioxide needed for? Water O2 Sugars CO2 Provides Carbon to make sugar in the Calvin Cycle Chloroplast Chloroplast NADP+ ADP + P Light- Dependent Reactions Calvin Cycle ATP NADPH

Photosynthesis Light Reaction 5) What product is made at the end of the Calvin Cycle? Water O2 Sugars CO2 Sugar (Glucose) Chloroplast Chloroplast NADP+ ADP + P Light- Dependent Reactions Calvin Cycle ATP NADPH

Photosynthesis Light Reaction 6) What two low energy molecules are produced at the end of the Calvin Cycle? Water O2 Sugars CO2 Chloroplast ADP + P NADP+ Chloroplast NADP+ ADP + P Light- Dependent Reactions Calvin Cycle ATP NADPH

Location of Reactions The light reaction takes place in the thylakoid membranes. The Calvin Cycle takes place in the stroma. The light reaction requires energy from the sun

10) Which part of photosynthesis uses ATP to make energy? The Calvin Cycle Water O2 Sugars CO2 What kind of energy storage molecule is made using the energy from ATP? Chloroplast Chloroplast NADP+ ADP + P Light- Dependent Reactions Calvin Cycle ATP NADPH Sugar

Calvin Cycle Overview Animation 1 Animation 2

Chapter 9 Chemical Pathways Cellular Respiration Biology Chapter 9 Chemical Pathways

Vocabulary Aerobic Anaerobic calorie Cellular respiration Fermentation Glycolysis

Basic Need for Energy Energy in Food: What is the difference between a: calorie(lower case c) and Calorie (upper case C)? A calorie is the amount of energy needed to raise the temperature of 1 gram of water by 1 degree C. A Calorie is a kilocalorie, or 1000 calories For example, 1 gram of glucose releases 3811 calories, on a food label 3.8 Calories

Basic Need for Energy Energy in Food: Organisms cannot use glucose directly, it must be broken down into smaller units. This process in living things begins with glycolysis. If oxygen is present, glycolysis is followed by the Krebs Cycle and electron transport chain – This is called Cellular Respiration

An Overview: Cellular Respiration The equation for cellular respiration is exactly the opposite of photosynthesis. Equation: 6O2 + C6H12O6  6CO2 + 6H2O and energy

Breaking Down Energy Slowly: Glucose needs to be broken down in small steps so that energy is not wasted.

First Step: Glycolysis Definition: The process of breaking the glucose in half to forming 2 molecules of pyruvate, a 3 carbon chain. Uses 2 ATP to start reaction Produces 4 ATP and 2 NADH

Glycolysis Does not require oxygen Very Fast – thousands of ATP produced in milliseconds Stops when it runs out of NAD+ (electron carrier) If oxygen is available: Cellular respiration starts If oxygen is NOT available, to make more NAD+, your body goes through fermentation. This way ATP can be made even without Oxygen.

Why use ATP in Glycolysis if you want ATP? You have to use a little energy to make even more energy. Like a bank, you put money in to earn interest. Animation

Fermentation Fermentation is releasing energy in the absence of oxygen. It is an ANAEROBIC process. Ultimately it allows NADH to be converted to NAD+, allowing glycolysis to continue. There are two main types of fermentation Alcoholic Fermentation Lactic Acid Fermentation

Alcoholic Fermentation Alcoholic fermentation is found in Yeasts, and a few other microorganisms. The equation is: Pyruvic acid + NADH  alcohol + CO2 + NAD+ Note: Carbon Dioxide is also produced, so when yeast conducts fermentation, there is the release of carbon dioxide as well as alcohol.

Alcoholic Fermentation Alcoholic fermentation diagram

Lactic Acid Fermentation Pyruvic acid from glycolysis can be converted to lactic acid. This conversion regenerates NAD+ for glycolysis to continue The equation is: Pyruvic acid + NADH  lactic acid + NAD+ Lactic acid fermentation is used by muscles when they run out of oxygen, ultimately causing soreness. Lactic acid is also created by unicellular organisms in the production of cheese, pickles, kimchi and other foods.

Lactic Acid Fermentation Lactic Acid fermentation diagram

Krebs Cycle In the Krebs Cycle, pyruvic acid is broken down into carbon dioxide.

Krebs Cycle Where does it occur: Mitochondria It requires oxygen – it is AEROBIC It is also known as the Citric Acid Cycle

Krebs Cycle So far, from 1 glucose Glycolysis produced: 2 NADH and 2 ATP Krebs Cycle produced: 8 NADH and 2 FADH2 and 2 ATP Animation

Krebs Cycle What happens to the Krebs cycle products? Carbon Dioxide is released to the atmosphere ATP is used for cellular activities NADH and FADH2 are used in the electron transport chain to produce large amounts of ATP

Electron Transport Chain Uses the high energy electrons from the Krebs cycle to convert ADP into ATP

Electron Transport Chain Where does it occur: Inner membrane of the Mitochondria It requires oxygen – it is AEROBIC

Electron transport chain

Cellular Respiration totals So far, from 1 glucose Glycolysis: 2 ATP + Krebs Cycle: 2 ATP + Electron Transport: 32 ATP Totals: 36 ATP from 1 glucose This is 38% efficiency The rest of the energy is released as heat

Energy use by humans Cells contains small amounts of ready ATP About 5 seconds worth After that, your body uses lactic acid formation This lasts for about 90 seconds You breathe hard to get rid of the lactic acid buildup For exercise longer than 90 seconds, cellular respiration is used This is a slow method to generate ATP Glycogen (a form of carbohydrate) is used for the first 15-20 minutes of cellular respiration After that other molecules, such as fats, are broken down