Chapter 4 Bio
you can make ATP from more than just glucose
other foods enter the cell resp pathway at differetn points
Why do plants and animls rely on each other for survival?
photosynthesis & cellular respiration are opposites of each other
What is th only step bacteria goes through and why?
glycolisis because it does not have a mitochondria
Where does the "photo" reaction occur?
in the thylakoids of the leaves chlorplasts
What happens when light energy (photon) hits the chlorophyll?
it excites one of the chlorphyll's electrons
no oxygen
no kreb cycle
Calvin Cycle
- light independent reaction - series of chemical reactions - occurs in stroma - enzymes are recycled
Energy Conversions
- All life depends on capturing energy from the sun and converting it into a form that living organisms can use. - Two key processes (mirror eachother) - Photosynthesis (Sun -> Plants) - Cellular respiration (Plants/Animals -> energy)
Kebs cycle payoff
- CO2 -> exhaled from body - 2 ATP -> used for energy - NADH -> goes to electron transport chain - FADH2 -> goes to electron transport chain
Biofuels and Fossil Fuels
- Chains of carbon and hydrogen atoms -Energy is stored in the bonds - Animal fats and oils - The activities of living organisms are fueled by breaking chemical bonds and harnessing the released energy. - Like gasoline, fats and oils contain chains of carbon and hydrogen atoms bound together, and just as with gasoline, breaking these bonds releases large amounts of energy (and water and CO2).
Organelles found in plants
- Endoplasmic reticulum - Nucleolus - Nuclear membrane - Nucleus - cytosplasm - cell membrane - cell wall - vacuole - chloroplast - Ribosomes - mitochondria
Chemical energy
- Food has potential energy stored in its chemical bonds CHEMICAL ENERGY - Respiration is breaking those bonds and releasing that energy *Plants store energy as sugar *Animals store energy as fat (more efficient because it doesn't bind to H20)
Energy has two forms
- Kinetic =Energy of motion - Light / heat - Potential = Stored energy - Chemical
ATP molecules
- Light energy has to be converted into chemical energy in ATP molecules. - Plants change light into sugar molecules and both plants and animals change sugar into ATP molecules, which allows for our survival
How do cells directy fuel their chemical reactions?
- None of the light energy from the sun can be used directly to fuel cellular work. - First it must be captured in the bonds of a molecule called adenosine triphosphate (ATP).
Energy conversions
- Only ~1% of the energy released by the sun is captured by plants. - Converted into chemical bond energy (glucose) - What happens to the other 99%? - Reflected back into space, absorbed by land, changed to heat - back into space (probably about 30%) or absorbed by land, the oceans, and the atmosphere (about 70%), and mostly transformed into heat.
Adenosine Triphosphate
- Pop off the third phosphate group - ATP ADP + Phosphate group + energy release - Release a little burst of energy! - Use this energy to drive chemical reactions necessary for cellular functioning. - Building muscle tissue - Repairing a wound - Growing roots
Glucose
- Simple sugar - immediate energy - Made by plants via photosynthesis - Used by most organisms for energy
Chloroplasts parts
- Stroma = sac shaped organelle, location of "synthesis" reaction, where chemical energy is synthesized into sugar - in the stroma is Thylakoids = elaborate system of interconnected membrane structures which look like stacks of pancakes. Location of "photo" reaction, where light energy is converted into chemical energy
Importance of the sun
- Sun = ultimate source of E for all organisms - The energy from sunlight is stored in the chemical bonds of molecules. - When these bonds are broken, energy is released - Same for all fuel sources (food, fossil fuel, biofuel)
Sunflower seeds
- Sunflowers capture light energy and convert it to organic matter (including tasty seeds). Light Energy Glucose (Chemical Energy) 6CO2 + 6H2O + SUN C6H12O6 + 602
What is energy?>
- The capacity to do work - Work - Moving matter against an opposing force - Humans, plants, and all other living organisms need energy for their activities, from thinking to moving to reproducing
Take home message
- a huge amount of additional energy can be harvested by cells after glycolysis - first the end -product of glycolysis, pyruvate is chemically modified - then the krebs cycle the modified pyruvate is broken down stepy-by-step - releases carbon molecules to the atmosphere as bonds are broken - captures some of the released energy in two ATP molecules and numerous high-energy electron carriers
Advantages and disadvantages of C4
- advantage - water loss is minimized in warm climates - disadvantage - requires more energy
Fermentation
- anaerobic respiration - no oxygen present, but still make ATP! - Only goes through glycolysis which produces to ATP
Summary of cellular respiration
- breaking glucose into 2 - occors in cytoplasm - does not require oxygen known as anarobic respiration that does not require O2 oxygen fermentations - 2 ATP
Calvin Cycle overall...
- carbon from CO2 in the atmosphere is attached (fixed) to molecules in chloroplasts, sugars are built, and molecules are regenerated to be used again in the calvin cycle - these processes consume energy from ATP and NADPH (the products of the "photo" part of photosynthesis
ATP structure
- center of ATP are two of these components : a small sugar molecule attached to a molecule called adenine. - adenine is a chain of three negatively charged phosphate molecule groups (hence the "tri" in triphosphate). - Because the bonds between these three phosphate groups must hold the groups together in the face of the three electrical charges that all repel one another, each of these bonds contains a large amount of energy and is stressed and unstable. - The instability of these high-energy bonds makes the three phosphate groups like a tightly coiled spring or a twig that is bent almost to the point of breaking. - With the slightest push, one of the phosphate groups will pop off, releasing a little burst of energy that the cell can use.
Electrons are passed to other molecules
- chief way energy moves through cells - molecules that gain electrons always carry greater energy than before receiving them - can view this as passing of potential energy from molecule to molecule
CAM plants
- close stomata during hot dry days - at night, when it's cooler, stomata open, CO2 let in and temporarily stored - during day, CO2 slowly used to make glucose while stomata are closed
Glycolisis net result
- each glucose molecule broken down into two molecules of pyruvate - ATP molecules produced - NADH molecules stroe high-energy electrons
Human example of cellular respiration
- eat food - digest food - absorb nutrient molecules into bloodstream - deliver nutrient molecules to the cells - at this point our cells can begin to exctract some of the energy through cellular respirtation - stored in the bonds of the food molecules - more bonds = more energy
Prep Phase of glycolisis
- glucose is very stable. First we need to make it unstable, so it breaks more easily
Why do we breath O2
- in to capture that free electron - ate the very end we still have our free floating electron which can damage our tissues - oxygen is now negatively charged, and combines with H+ to produce H2O, which is harmless!
"photo"
- light dependent reaction - sunlight produces ATP and NADPH (also energy moledule) - water produces oxygen
Cellular Respiration Overall
- living organisms extract energy through cellular respirationin which the high-energy bonds of sugar are broken, releasing energy, useful for life's chemical reactions - the cell captures the food molecules' stored energy in the bonds of ATP molecules - this process requires fuel molecules and oxygen and it yields ATP molecules, water, and carbon dioxide
anaerobic respiration
- mamals/humans - viguros exercise - o2 used up faster than needed so more ATP provided by glycolisis - lactate build up - in muscle PH decrease in blood causing muscle fatigue
Step 4: Electron Transport Chain
- most amount of ATP made here - On the mitochondrial inner membrane (cristae) - can poduce 32 - 34 ATP (most efficient)
Evolutionary Adaptations
- normal plants = C3 plants (photosynthesis) - when its too hot, they "shut down" to prevent water loss, but lose out on photosynthesis - C4 and CAM plants thrive in hot, dry conditions - reduce evaporative water loss
C4 plants
- occur in hot and dry climates - produce ultimate "CO2 - sticky tape" enzyme that creates a CO2 bank - these plants grab more CO2 than C3 plants - photosynthesis adds an extra set of steps
Fermentation review
- oxygen deficiency limits the breakdown of fuel because ETC needs oxygen as the final acceptor of the electrons generated during glycolosis and the krebs cycle - when oxygen is unavailable, yeast resort to fermentation, in which they use a differnt electron acceptor, pyruvate, generating ethano in the process-alcoholic beverages & bread
Products from the "photo" portion
- oxygen, ATP and NADPH - Time for the "synthesis" part
Plants go through what?
- photosynthesis - cellular respiration
Plant pigments
- plant pigements can only absorb specific wavelengths of energy - Therefore, plants produce several different types of pigments - clorophyll a - chlorophyll b - caratenoids - Accessory Pigments: xanthophyll, anthocyannin - each pigment absorbs a different wavelength, so plants can maximize the energy from light
Chlorophyll
- plant pigment found inside chloroplasts - absorb certain wavelengths of energy (photons) from the sun - absorbed energy excites electrons - has bonds in it
How do living organisms fuel their actions?
- plants - make glucose from light energy (photsynthesis) - animals - eat food and break it down into glucose subunits - Both change glucose into useable energy
Stomata
- pores of gas exchange - openings on leaves taht allow gas exchange
Cellular respiration
- purpose is to produce ATP(energy stored in chemical bonds of sugar) and breakdown glucose in ATP - converts food molecules into ATP, a universal source of energy for living organisms - requires 1 fuel and 2 oxygen - Breaks bonds to relase the high-energy electrons captured in ATP - Oxygen is electon magnet Input = oxygen + sugar Output = Carbond dioxide + water + ATP C6H12O6 (food) + 6O2 (air) = 6CO (air) + 6H20 (air) + ATP (used in body)
Visible Spectrum
- range of energy human see as light - ROYGBIV - Pigments = biological molecules that absorb light - what you see is the wavelength of light the pigment does not use
Electromagnetic Spectrum
- range of energy that is organized into waves of different lengths - shorter the wavelengths, higher the energy
Photosynthesis in detail
- the energy of sunlight is captured as chemical energy
Gycolisis review
- the initial phase in the process by which all living organisms harness energy from food molecules - occurs in a cell's cytoplasm and uses the energy released fromm breaking chemical bonds in food molecules to produce high-energy molecules, ATP and NADH
ETC review
- the largest energy payoff of cellular respiration comes as electrons from NADH and FADH2 produced during glycolysis and the Krebs cycle move along the electron transport chain - the electrons are passed from one carrier to another and energy is released, pumping protons into the intermembrane space - As the protons rush back to the inner mitochondrial matrix, the force of their fuels the production of large amounts of ATP
Cellular Respiration
- the process by which all living organisms release the energy stored in the chemical bonds of food molecules and use it to fuel their lives. - plants, animals and fungi release the energy stored in the chemical bonds of food molecules and use it as fuel
Photosynthesis
- the process by which plants capture energy from the sun and store it in the chemical bonds of sugars and other food molecules they make - Plants capture energy from the sun and store it in the chemical bonds of sugars and other food molecules - uses energy from sunlight to make food
The 2nd photosystem
- the same steps occur again, except - no water is needed - NADPH is made, not ATP
Mitochondria
- two key features of mitochondria are essential to their ability to harness energy from molecules: 1) mitochondrail bag within a bag structure 2) electron carriers organized within the inner bag - studed with molecuels creat an ETC that enables ATP production
Light
- type of kinetic energy - made up of little energy packets called photons - different photons carry different amounts of energy, carried as waves - length of the wave = amount of energy the photon contains
Synthesis
- were glucose is made - the captured energy of sunlight is used to make food
Steps of calvin cycle
1) FIXATION - rubisco (enzyme) changes atmospheric (unuseable) Co2 into usable from (G3P) - Co2 -> useable carbon 2) SUGAR CREATION - changing (G3P) into glucose - create sugar useable glucose *ultimate goal H from NADPH 3) REGENERATION - recycle the enzymes necessary to start all over - remakes all enzymes
Two potenial fates of excited electrons
1) electron returns to resting, unexcited state. - energy released 2) excited electrons are passed to other atoms
Laws thermodynamics
1. Energy can never be created or destroyed, it can only change from one form to another. Ex:Light Energy -> Chemical Energy via Photosynthesis 2. Every conversion of energy includes the transformation of some energy into heat Usually lost to the atmosphere
Cellular Respiration Steps
1. Glycolysis - occurs in cytoplasm & produces 2 ATP 2. Acetyl Co-A production - occurs in mitochondria 3. Krebs Cycle - occurs in mitochondria & produces 2 ATP 4. Electron Transport Chain - occurs in mitochondria & produces 32 - 34 ATP
The 1st photosystem
1a) sun excites an e-, whcih bounces around and is finally sent to step 2 1b) water is split to replenish that lost e- and creates oxygen (waste) 2a) e- are passed from one proton pump to the next, energy is released, forcing H+ ions into thylakoid. E- goes to step 3 2b) H+ rush bac ( facilitated diffusion), creating ATP in the process
In what form is energy lost
1heat
Laws of thermo
1st - light energy of sun, chemical energy stored in plants 2nd - energy lost in the form of heat - As energy is converted to do work, some energy is released as heat. - Heat is a much less useful form of energy than the energy transformed into chemical energy in plants.
Photosystem
= cluster of chlorphyl & proteins -> absorbs light
Recycling in the cell
ADP + phosphate group + energy = ATP - can be used and recycled hundreds of thousands of times - Energy to make ATP comes from sunlight or from energy stored in chemical bonds. - Each time a cell expends one of its ATP molecules to pay for an energetically expensive reaction, a phosphate is broken off and energy is released. - What is left is a molecule with two phosphates, called ADP (adenosine diphosphate), and a separate phosphate group (labeled Pi) - An organism can then use ADP, a free-floating phosphate, and an input of kinetic energy to rebuild its ATP stocks. - The kinetic energy is converted to potential energy when the free phosphate group attaches to the ADP molecule and makes ATP. - In this manner, ATP functions like a rechargeable battery.
Step 3
Krebs Cycle (occus 2x in mitochondria) - requires Ox to occur
3 parts to krebs cycle
Part 1: 2C Acetyl CoA + 4C Oxaloacetate = 6c glucose precuror * acetyl CoA moleucle (from glycolysis) enters the cycle and binds to oxaloacetate, creatinga six-carbon molecule Part 2: 6C molecules gets rid of 2 CO2 (both have 1 C) - electrons made and captures by NADH * High-energy electron carriers (NADH) are made and carbon dioxide is exhaled - the 5 carbon molecule donates electrons to NAD+ creating NADH. Two carbon dioxide molecules are released into the atmosphere Part 3: Leftover 4C molecule is changed back into Oxaloacetate - 2 TP and electrons made (FADH2 and NADH) * Oxaloacetates is re-formed, ATP is generated and more high-energy electron carriers are performed. The remaining four-carbon molecule is rearranged to form oxaloacetate. In the process, ATP is formed and electrons are passed to NADH and FADH2 (ecarriers)
Thermodynamics
The study of the transformation of energy from one type to another, such as from potential energy to kinetic energy
Chemical energy
a form of potential energy stored in chemical bonds
ATP
a free-floating molecule found in cells that acts like a rechargeable battery that temporarily stores energy that can then be used for cellular work in plants, animals, bacteria, and all the other organisms on earth. - Adenosine Triphosphate - Nucleic Acid made of 1 nucleotide - High energy molecule
What does life depend on?
capturing energy from the sun and converting it into a form that living organisms can use
ATP molecules
cellular currency - Adenosine TriPhosphate
What type of energy is food?
chemical energy
Where does photosynthesis take place
chloroplasts
Input vs output
input = sunlight + water + carbon dioxide output = oxygen + sugar
Photo reaction
energy from sun captured and stored - oxygen added to atmosphere - energy used to build sugar molecules - sugars used to produce plant structures - water absorbed from ground through roots Light dependent reactions
Synthesis reaction
energy is used to build sugar molecules - carbon dioxide absorbed from atmosphere - sugar used to produce plant structures Light independent reactions a.k.a. Calvin Cycle
Step 2
prep phase to krebs cycle - pyruvate needs to be changed into a more useable form - pyruvate + Coenzyme A = Acetyl CoA - Acetyl CoA is useful - this process occurs 2x (since 1 glucose makes 2 pyruvates) - Coenzyme A: your body makes this from molecules found in foods like whole grains, yogurt, avocado
aerobic respiration
requires oxygen 34 - 36 ATP
Besides plants what what else is capable of photsynthesis
some bacteria and other unicellular organisms
When humans grow where does the new matter come from?
the food we eat
Prtoton Gradietns and potential energy
the force of the flow H+ ions fuels the attachment of free-floating phosphate groups to ADP to produce ATP(which is held together by covalent bonds)
Glycolisis
the universal energy-releasing pathway - all living things (including bacteria) - "glucose - break" - occurs in cytoplasm 2 pyruvates (2 of 3 carbon rings) + ATP + free electrons
Crrency exchange
this time from food molecules into ATP by cellular respiration - we need to change food into ATP molecule (form of chemical energy)
Why does the calvin cycle need to form 2x
to make one glucose 2 G3P is needed and only 1 is formed per cycle
Free electrons
unstable by themselves NAD+ captures the 2 e- turning into NAD- - because he's negative, he's attracted to free floating H+ ions, thus becoming NADH(charged) NAD- + H+ = NADH 02 is necessary
Pyoff phase of glycolisis
when it finaly breaks it relases ATP(4), NADH(2) and water