By-Products of the Meat Industry

Bioproducts - Plywood Manufacturing

Bioproducts Manufacturing (MEEN 4151/5151) – Spring 2026 Homework #2

nutrition - byproduct feeds

Chapter 17 Vocabulary: Cost Allocation - Joint Products and Byproducts

Chapter 17: Cost Allocation - Joint Products and Byproducts

Animal Feed Ingredients: Grains, Legumes, and Byproducts

Chapter 20: Autoregulation - Metabolic Byproducts

Conversion of carbon dioxide to glucose and oxygen as a byproduct

Food Components & Digestive Byproducts

System Interactions in Animals Tools Finish System Interactions in Animals The human body is made of many different organ systems. Each system performs unique functions for the body, but the systems also interact with each other to perform more complex functions. Major Organ Systems Body Systems In humans, cells, tissues, and organs group together to form organ systems. These systems each perform different functions for the human body. The major organ systems and their functions in humans include: The Nervous System — The nervous systems consists of two parts. The central nervous system consists of the brain and spinal cord, while the peripheral nervous system consists of nerves that connect the central nervous system to other parts of the body. The brain plays an important role in interpreting the information picked up by the sensory system. It helps in producing a precise response to the stimuli. It also controls bodily functions such as movements, thoughts, speech, and memory. The brain also controls many processes related to homeostasis in the body. The spinal cord connects to the brain through the brainstem. From the brainstem, the spinal cord extends to all the major nerves in the body. The spinal cord is the origin of spinal nerves that branch out to various body parts. These nerves help in receiving and transmitting signals from various body parts. The spinal cord helps in reflex actions of the body The smallest unit of the nervous system is the nerve cell, or neuron. Neurons communicate with each other and with other cells by producing and releasing electrochemical signals known as nerve impulses. Neurons consist of the cell body, the dendrites, and the axon. The cell body consists of a nucleus and cytoplasm. Dendrites are specialized branch-like structures that help in conducting impulses to and from the various body parts. Axons are long, slender extensions of the neuron. Each neuron possesses just a single axon. Its function is to carry the impulses away from the cell body to other neurons. The Circulatory System — The circulatory (or cardiovascular) system is composed of the heart, arteries, veins, and capillaries. The circulatory system is responsible for transporting blood to and from the lungs so that gas exchange can take place. As the circulatory system pumps blood throughout the body, dissolved nutrients and wastes are also delivered to their destinations. The heart is a muscular organ roughly the size of an adult human's closed fist. It is present behind the breastbone, slightly to the left. It consists of four chambers: right atrium, left atrium, right ventricle, and left ventricle. The heart receives deoxygenated blood from the body and pumps this blood to the lugs, where it is oxygenated. The oxygen-rich blood reenters the heart and is then pumped back through the body. The circulatory system is responsible for transporting blood to and from the lungs so that gas exchange can take place. As the circulatory system pumps blood throughout the body, dissolved nutrients and wastes are also delivered to their destinations. Blood circulation takes place through blood vessels. Blood vessels are tubular structures that form a network within the body and transport blood to each tissue. There are three major types of blood vessels: veins, arteries, and capillaries. Veins carry deoxygenated blood from the body to the heart, except for pulmonary veins, which carry oxygenated blood from the lungs to the heart. Arteries carry oxygenated blood from the heart to different organs, except for the pulmonary artery, which carries deoxygenated blood from the heart to the lungs. The arteries branch out to form capillaries. These capillaries are thin-walled vessels through which nutrients and wastes are exchanged with cells. The Respiratory System — The main structures of the respiratory system are the trachea (windpipe), the lungs, and the diaphragm. When the diaphragm contracts, it creates a vacuum in the lungs that causes them to fill with air. During this inhalation, oxygen diffuses into the circulatory system while carbon dioxide diffuses out into the air that will be exhaled. The trachea branches out into two primary bronchi. Each bronchus is further divided into numerous secondary bronchi. These secondary bronchi further branch into tertiary bronchi. Finally, each tertiary bronchus branches into numerous bronchioles. Each bronchiole terminates into a tiny, sac-like structure known as an alveolus. The walls of each alveolus are thin and contain numerous blood capillaries. The process of gaseous exchange occurs in these alveoli. The diaphragm is a dome-shaped muscle situated at the lower end of the rib cage. It separates the abdominal cavity from the chest cavity. During inhalation, the diaphragm contracts, and the chest cavity enlarges, creating a vacuum that allows air to be drawn in. This causes the alveoli in the lungs to expand with air. During this process, oxygen diffuses into the circulatory system while carbon dioxide diffuses out into the air that will be exhaled. On the other hand, expansion of the diaphragm causes exhalation of air containing carbon dioxide. The Digestive System — The digestive system consists of the mouth, stomach, small intestine, large intestine, and anus. It is responsible for taking in food, digesting it to extract energy and nutrients that cells can use to function, and expelling the remaining waste material. Mechanical and chemical digestion takes place in the mouth and stomach, while absorption of nutrients and water takes place in the intestines. The digestive system begins at the mouth, where food is taken in, and ends at the anus, where waste is expelled. The food taken into the mouth breaks into pieces by the grinding action of the teeth. Carbohydrate digestion starts in the mouth with the breakdown of carbohydrates into simple sugars with the help of salivary enzymes. The chewed food, known as a bolus, enters the stomach through the esophagus. The bolus mixes with acids and enzymes released by the stomach. Protein digestion starts in the stomach as proteins are broken down into peptides. This partially digested food is known as chyme. Chyme enters the small intestine and mixes with bile, a substance secreted by the liver, along with enzymes secreted by the pancreas. The digestion of fats starts in the small intestine as bile and pancreatic enzymes break down fats into fatty acids. The surface of the small intestine consists of hair-like projections known as villi. These villi help in absorbing nutrients from the digested food. The digested food enters the large intestine, or colon, where water and salts are reabsorbed. Any undigested food is expelled out of the body as waste. The Skeletal System — The skeletal system is made up of over 200 bones. It protects the body's internal organs, provides support for the body and gives it shape, and works with the muscular system to move the body. In addition, bones can store calcium and produce red and white blood cells. The Muscular System — The muscular system includes more than 650 tough, elastic pieces of tissue. The primary function of any muscle tissue is movement. This includes the movement of blood through the arteries, the movement of food through the digestive tract, and the movement of arms and legs through space. Skeletal muscles relax and contract to move the bones of the skeletal system. The Excretory System — The excretory system removes excess water, dangerous substances, and wastes from the body. The excretory system also plays an important role in maintaining body equilibrium, or homeostasis. The human excretory system includes the lungs, sweat glands in the skin, and the urinary system (such as the kidneys and the bladder). The body uses oxygen for metabolic processes. Oxygen metabolism results in the production of carbon dioxide, which is a waste matter. The lungs expel carbon dioxide through the mouth and nose. The liver converts toxic metabolic wastes, such as ammonia, into less harmful susbtances. Ammonia is converted to urea, which is then excreted in the urine. The skin also expels urea and small amounts of ammonia through sweat. The skin is embedded with sweat glands. These glands secrete sweat, a solution of water, salt, and wastes. The sweat rises to the skin's surface, where it evaporates. The skin maintains homeostasis by producing sweat in hot environments. Sweat production cools and prevents excessive heating of the body. Each kidney contains about a million tiny structures called nephrons, which filter the blood and collect waste products, such as urea, salts, and excess water that go on to become urine. The Endocrine System — The endocrine system is involved with the control of body processes such as fluid balance, growth, and sexual development. The endocrine system controls these processes through hormones, which are produced by endocrine glands. Some endocrine glands include the pituitary gland, thyroid gland, parathyroid gland, adrenal glands, thymus gland, ovaries in females, and testes in males. The Immune System — The immune system is a network of cells, tissues, and organs that defends the body against foreign invaders. The immune system uses antibodies and specialized cells, such as T-cells, to defend the body from microorganisms that cause disease. The Reproductive System — The reproductive system includes structures, such as the uterus and fallopian tubes in females and the penis and testes in males, that allow humans to produce new offspring. The reproductive system also controls certain hormones in the human body that regulate the development of sexual characteristics and determine when the body is able to reproduce. The Integumentary System — The integumentary system is made up of a person's skin, hair, and nails. The skin acts as a barrier to the outside world by keeping moisture in the body and foreign substances out of the body. Nerves in the skin act as an interface with the outside world, helping to regulate important aspects of homeostasis, such as body temperature. Interacting Organ Systems The organ systems work together to perform complex bodily functions. The functions of regulation, nutrient absorption, defense, and reproduction are only possible because of the interaction of multiple body systems. Regulation All living organisms must maintain homeostasis, a stable internal environment. Organisms maintain homeostasis by monitoring internal conditions and making adjustments to the body systems as necessary. For example, as body temperature increases, skin receptors and receptors in a region of the brain called the hypothalamus sense the change. The change triggers the nervous system to send signals to the integumentary and circulatory systems. These signals cause the skin to sweat and blood vessels close to the surface of the skin to dilate, actions which dispel heat to decrease body temperature. Both the nervous system and the endocrine system are typically involved in the maintenance of homeostasis. The nervous system receives and processes stimuli, and then it sends signals to body structures to coordinate a response. The endocrine system helps regulate the response through the release of hormones, which travel through the circulatory system to their site of action. For example, the endocrine system regulates the level of sugar in the blood by the release of the hormones insulin, which stimulates uptake of glucose by cells, and glucagon, which stimulates the release of glucose by the liver. The nervous and endocrine systems interact with the excretory system in the process of osmoregulation, the homeostatic regulation of water and fluid balance in the body. The excretory system expels excess water, salts, and waste products. The excretion of excessive amounts of water can be harmful to the body because it reduces blood pressure. If the nervous system detects a decrease in blood pressure, it stimulates the endocrine system to release antidiuretic hormone. This hormone decreases the amount of water released by the kidneys to ensure appropriate blood pressure. Appropriate levels of carbon dioxide in the blood are also maintained by homeostatic mechanisms that involve several organ systems. Excess carbon dioxide, a byproduct of cellular respiration, can be harmful to an organism. As blood circulates throughout the body, it picks up carbon dioxide waste from cells and transports it to the lungs, where it is exhaled while fresh oxygen is inhaled. If the concentration of carbon dioxide in the blood increases above a certain threshold, the nervous system directs the lungs to increase their respiration rate to remove the excess carbon dioxide, which ensures that the levels of carbon dioxide in the blood are maintained at appropriate levels. In this way, the circulatory, respiratory, and nervous systems work together to limit the level of carbon dioxide in the blood. Nutrient Absorption To absorb nutrients from food, the nervous, digestive, muscular, excretory, and circulatory systems all interact. The nervous system controls the intake of food and regulates the muscular action of chewing, which mechanically breaks down food. As food travels through the stomach and intestines, the digestive system structures release enzymes to stimulate its chemical breakdown. At the same time, the muscular action, called peristalsis, of the muscles in the wall of the stomach help churn the food and push it through the digestive tract. In the intestines, nutrients from food travel across the surfaces of the villi. The nutrients are then picked up by the blood, and the circulatory system transports the nutrients throughout the cells of the body. The endocrine system releases hormones, such as insulin, that control the rate at which certain body cells use nutrients. Any excess minerals, such as calcium, in the blood are deposited in and stored by the skeletal system. Waste products produced by the use of nutrients, as well as the leftover solid waste from the digestion of food, exit the body through the excretory system. Throughout the process of nutrient absorption, the nervous system controls the muscles involved in digestion, circulation, and excretion. Defense Several body systems interact to defend the body from external threats. The body's first line of defense is the integumentary system, which provide a physical barrier that prevents pathogens from entering the body. The skin of the integumentary system also contains receptors for pain, temperature, and pressure. If an unpleasant stimulus is encountered, these receptors send signals to the central nervous system. In response, the central nervous system sends commands to the muscles to move the body part away from the stimulus. In this way, the integumentary, nervous, and muscular systems interact to prevent damage to the body. In the event of a break in the skin, the nervous, immune, lymphatic, and circulatory systems work together to repair the wound and protect the body from pathogens. When the skin is broken, specialized blood cells called platelets form a clot to stop the bleeding. These platelets also release chemicals that travel through the circulatory system and recruit cells, like immune system cells, to repair the wound. These immune cells, or white blood cells, are transported by the circulatory and lymphatic systems to the site of the wound, where they identify and destroy potentially pathogenic cells to prevent an infection. Some lymphocytes, white blood cells produced by the lymphatic system, also produce antibodies to neutralize specific pathogens. All of the white blood cells involved in the body's response were originally produced in the bone marrow of the skeletal system. If an infection does occur

OG 4.13 Portland Fire & Rescue Combustion Byproducts Exposure Guidelines

acycst2 joint products and byproducts

Quiz 12 - Joint Products and Byproducts

Here are the answers to your biology questions: 1. Definitions: * Metabolism: The sum total of all chemical reactions that occur within a living organism. * Catabolism: The breakdown of complex molecules into simpler ones, releasing energy. * Anabolism: The synthesis of complex molecules from simpler ones, requiring energy input. * Endergonic Reaction: A reaction that requires an input of energy to proceed. * Exergonic Reaction: A reaction that releases energy. 2. Role of Enzymes in Metabolism: Enzymes are biological catalysts that speed up chemical reactions by lowering the activation energy. They bind to specific substrates, forming an enzyme-substrate complex, and catalyze the reaction. This allows metabolic processes to occur at rates compatible with life. 3. Enzyme Activity: * Activation Energy: The minimum amount of energy required for a reaction to occur. * Catalyst: A substance that speeds up a chemical reaction without being consumed in the process. * Active Site: The specific region on an enzyme where the substrate binds. * Denaturation: The loss of an enzyme's shape and function, often due to extreme temperature or pH. * Substrate: The molecule upon which an enzyme acts. * Enzyme-Substrate Complex: A temporary complex formed when an enzyme binds to its substrate. * Suffix -ase: Commonly used to denote enzymes, such as sucrase, protease, and lipase. 4. Oxidation-Reduction Reactions in Cellular Respiration: In cellular respiration, oxidation-reduction reactions involve the transfer of electrons and hydrogen ions. Oxidation is the loss of electrons (and often hydrogen atoms), while reduction is the gain of electrons (and often hydrogen atoms). Energy is released during these reactions and is used to produce ATP. 5. Balanced Equation for Cellular Respiration: C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + energy (ATP) 6. Structure of a Mitochondrion: * Outer Membrane: Encloses the mitochondrion. * Inner Membrane: Folded into cristae, increasing surface area for ATP production. * Intermembrane Space: The space between the outer and inner membranes. * Matrix: The fluid-filled space inside the inner membrane, containing enzymes for the citric acid cycle. 7. Glycolysis: Glycolysis is the breakdown of glucose into pyruvate. It occurs in the cytoplasm and produces 2 ATP, 2 NADH, and 2 pyruvate molecules. 8. Citric Acid Cycle: The citric acid cycle, also known as the Krebs cycle, occurs in the mitochondrial matrix. It completely oxidizes pyruvate, producing 2 ATP, 6 NADH, and 2 FADH₂ molecules per glucose molecule. 9. Electron Transport Chain and Oxidative Phosphorylation: The electron transport chain is a series of protein complexes embedded in the inner mitochondrial membrane. Electrons from NADH and FADH₂ are transferred through the chain, releasing energy that is used to pump protons into the intermembrane space. The resulting proton gradient drives ATP synthesis through ATP synthase. 10. ATP and NADH Production: * Glycolysis: 2 ATP, 2 NADH * Citric Acid Cycle: 2 ATP, 6 NADH, 2 FADH₂ * Electron Transport Chain: ~32 ATP (from NADH and FADH₂) 11. Structure and Function of a Dicot Leaf: Dicot leaves are typically broad and flat, with a network of veins. They have a waxy cuticle to prevent water loss, stomata for gas exchange, and mesophyll cells containing chloroplasts for photosynthesis. 12. Structure of a Chloroplast: * Thylakoid: A flattened, disc-shaped sac. * Thylakoid Membrane: The membrane surrounding the thylakoid. * Thylakoid Space: The interior of the thylakoid. * Stroma: The fluid-filled space outside the thylakoids. * Grana: Stacks of thylakoids. 13. Site of Light-Dependent and Light-Independent Reactions: * Light-Dependent Reactions: Thylakoid membrane * Light-Independent Reactions (Calvin Cycle): Stroma 14. Balanced Equation for Photosynthesis: 6CO₂ + 6H₂O + light energy → C₆H₁₂O₆ + 6O₂ * Carbon (C) from CO₂ is incorporated into glucose. * Hydrogen (H) from water (H₂O) is incorporated into glucose. * Oxygen (O) from water is released as O₂. 15. Dual Nature of Light: Light exhibits both wave-like and particle-like properties. As a wave, it has a wavelength and frequency. As a particle, it consists of photons, discrete packets of energy. 16. Light Reactions: Light energy is absorbed by pigments in photosystems I and II, exciting electrons. These electrons are transferred through a series of electron carriers, generating ATP and NADPH. Water is split, releasing oxygen as a byproduct. 17. Calvin Cycle: The Calvin cycle uses ATP and NADPH from the light reactions to fix CO₂ from the atmosphere. CO₂ is incorporated into RuBP, forming 3-PGA. 3-PGA is reduced to G3P, which can be used to synthesize glucose or regenerate RuBP. 18. Role of Photosynthetic Pigments: Photosynthetic pigments, such as chlorophyll a, chlorophyll b, and carotenoids, absorb light energy and transfer it to the reaction center of photosystems. 19. Role of Photosystems: Photosystems I and II are protein complexes containing pigments and electron carriers. They absorb light energy and use it to excite electrons, initiating the electron transport chain. 20. Phases of the Calvin Cycle: * Carbon Fixation: CO₂ is fixed to RuBP, forming 3-PGA. * Reduction: 3-PGA is reduced to G3P using ATP and NADPH. * Regeneration of RuBP: G3P is used to regenerate RuBP, allowing the cycle to continue. 21. ATP, NADPH, and CO₂ Requirements: * To produce 1 G3P molecule: 9 ATP, 6 NADPH, and 3 CO₂ * To produce 1 glucose molecule: 18 ATP, 12 NADPH, and 6 CO₂ I

byproducts

1. Molecular Forms and Their Functions in Photosynthesis Photosynthesis involves various molecular structures, each contributing to different stages of the process. The key molecular components involved in photosynthesis include: Chlorophyll: A pigment responsible for absorbing light energy, primarily in the blue and red wavelengths, and reflecting green light. Water (H₂O): Used in the light reactions, where it is split to provide electrons and protons (hydrogen ions). Carbon dioxide (CO₂): The source of carbon for the synthesis of glucose, incorporated in the Calvin cycle. ATP (Adenosine Triphosphate): The energy currency produced in the light reactions and used in the Calvin cycle. NADPH (Nicotinamide adenine dinucleotide phosphate): An electron carrier produced in the light reactions, used in the Calvin cycle for the reduction of CO₂. These molecules work in tandem to capture light energy and convert it into chemical energy, which is stored in the bonds of glucose. 2. Roles of Molecular Structures in Photosynthesis The key molecular structures in photosynthesis—chlorophyll, ATP, NADPH, and enzymes—are crucial for energy capture, conversion, and storage in plants. Chlorophyll absorbs light energy and drives the conversion of water into oxygen and electrons during the light reactions. ATP and NADPH are produced in these reactions and are then used in the Calvin cycle to synthesize sugars from carbon dioxide. 3. What is Photosynthesis? Why is it Important? Definition: Photosynthesis is the process by which plants, algae, and some bacteria convert light energy, carbon dioxide, and water into glucose (a form of sugar) and oxygen, using chlorophyll as the primary pigment. Importance: Photosynthesis is fundamental for life on Earth because it: Provides the oxygen necessary for cellular respiration in most organisms. Serves as the foundation of the food chain, producing organic compounds (like glucose) that form the base of energy for almost all living things. Helps regulate atmospheric CO₂ levels, thereby contributing to climate balance. 4. Theoretical Origins of the Chloroplast Chloroplasts are believed to have evolved from cyanobacteria (blue-green algae) through a process called endosymbiosis. This theory suggests that an ancient eukaryotic cell engulfed a photosynthetic prokaryote (cyanobacterium), which then became a permanent part of the host cell. Over time, the engulfed cyanobacterium evolved into the modern chloroplast, retaining its own DNA and two membranes, which are characteristic of bacteria. 5. Where Does Photosynthesis Take Place? In What Type of Cells? Location: Photosynthesis primarily takes place in the chloroplasts of plant cells. Cell Type: Photosynthetic cells are typically found in mesophyll cells in the leaves of plants. These cells contain a high concentration of chloroplasts, which are essential for capturing light energy. 6. Structures of the Chloroplast Stroma: The fluid-filled interior of the chloroplast, which contains enzymes involved in the Calvin cycle (dark reactions). Granum: Stacks of thylakoids, which are the sites of the light reactions. Thylakoid: Membrane-bound structures within the chloroplast that contain chlorophyll and other pigments necessary for light absorption. Thylakoid Space/Lumen: The interior space within each thylakoid where protons (H⁺) accumulate during the light reactions. Inner and Outer Membranes: The double membrane structure that surrounds the chloroplast, with the outer membrane being more permeable than the inner membrane. 7. What is Chlorophyll? Where is it Found in the Chloroplast? Chlorophyll: Chlorophyll is the green pigment in plants that absorbs light energy necessary for photosynthesis. There are two main types: chlorophyll a (primary pigment) and chlorophyll b (which assists chlorophyll a by capturing additional light wavelengths). Location in the Chloroplast: Chlorophyll is embedded in the thylakoid membranes of the chloroplasts. The thylakoids are where light absorption and energy conversion occur. 8. Chemical Reaction of Photosynthesis The general chemical equation for photosynthesis is: 6CO2+6H2O+light energy→C6H12O6+6O26CO_2 + 6H_2O + \text{light energy} \rightarrow C_6H_{12}O_6 + 6O_26CO2​+6H2​O+light energy→C6​H12​O6​+6O2​ Inputs: Carbon dioxide (CO₂): From the air. Water (H₂O): From the soil. Light energy: Captured by chlorophyll from sunlight. Outputs: Glucose (C₆H₁₂O₆): A sugar that stores chemical energy. Oxygen (O₂): A byproduct, released into the atmosphere. 9. Light Reactions of Photosynthesis Location: The light reactions take place in the thylakoid membranes. Inputs: Light energy (photons) Water (H₂O) Outputs: ATP (energy carrier) NADPH (electron carrier) Oxygen (O₂) as a byproduct In the light reactions, light energy is absorbed by chlorophyll, which excites electrons. These electrons are passed through the electron transport chain (ETC), leading to the production of ATP and NADPH. Water is split to replace the excited electrons, producing oxygen as a byproduct. 10. Calvin Cycle (Dark Reactions) Location: The Calvin cycle occurs in the stroma of the chloroplast. Inputs: CO₂ (from the atmosphere) ATP (from the light reactions) NADPH (from the light reactions) Outputs: Glucose (C₆H₁₂O₆) or other sugars that can be used for energy or stored as starch. In the Calvin cycle, carbon dioxide is fixed into an organic molecule through a series of reactions involving the enzyme RuBisCO. ATP and NADPH are used to reduce this organic molecule into sugars. 11. The Original Source of Electrons in Photosynthesis The original source of electrons in photosynthesis is water (H₂O). During the light reactions, water molecules are split by the enzyme photosystem II, releasing electrons, protons, and oxygen. The electrons are passed through the electron transport chain to ultimately reduce NADP⁺ to NADPH. 12. Difference Between Light Reactions and Calvin Cycle Light Reactions: Energy Source: Light energy from the sun. Major Outputs: ATP, NADPH, and O₂. Location: Thylakoid membranes. Calvin Cycle (Dark Reactions): Energy Source: ATP and NADPH produced during the light reactions. Major Output: Glucose (or other carbohydrates). Location: Stroma. The Calvin cycle is often called the "dark reactions" because it does not require light directly; instead, it uses the ATP and NADPH generated in the light reactions to power the fixation of carbon and the synthesis of sugars. 13. Carbon Fixation in Photosynthesis Carbon fixation refers to the process by which carbon dioxide (CO₂) from the atmosphere is incorporated into an organic molecule. In photosynthesis, this occurs during the Calvin cycle, where CO₂ is attached to a 5-carbon molecule called ribulose bisphosphate (RuBP), catalyzed by the enzyme RuBisCO. This process creates a 6-carbon intermediate that is quickly split into two molecules of 3-phosphoglycerate (3-PGA), which are then converted into sugars through a series of reactions. Summary Photosynthesis is essential for life, providing oxygen and forming the basis of the food chain. It occurs in the chloroplasts within plant cells, primarily in the mesophyll cells of leaves. Light reactions capture solar energy and convert it into ATP and NADPH, while releasing O₂. The Calvin cycle uses ATP and NADPH to fix CO₂ and synthesize glucose. Chlorophyll, water, ATP, and NADPH play key roles in harnessing and storing energy during photosynthesis. 1. Chloroplast and Chlorophyll – Differentiate Chloroplast: Definition: Organelles in plant and algal cells where photosynthesis occurs. They contain the necessary machinery for converting light energy into chemical energy (glucose). Structure: Chloroplasts have an outer membrane, an inner membrane, a stroma (fluid-filled space), and thylakoids (membrane-bound structures where light reactions take place). Function: Sites for both the light-dependent reactions (in thylakoid membranes) and the Calvin cycle (in the stroma). Chlorophyll: Definition: A green pigment found in the thylakoid membranes of chloroplasts that absorbs light for photosynthesis. Function: Absorbs light, primarily in the red (~680 nm) and blue (~450 nm) regions of the spectrum, and reflects green light (~500-550 nm), which is why plants appear green. 2. Photon and Wavelength – Define Photon: Definition: A particle of light or electromagnetic radiation. Photons carry energy and are absorbed by chlorophyll during photosynthesis. The energy of a photon is inversely proportional to its wavelength: shorter wavelengths carry more energy. Wavelength: Definition: The distance between successive crests of a wave, typically measured in nanometers (nm) for light. Different wavelengths correspond to different colors of light in the visible spectrum. 3. Wavelengths of Certain Colors of Light ~400 nm: Violet ~500 nm: Green (around this wavelength, light is least absorbed by chlorophyll, so it is reflected, contributing to the green color of leaves). ~550 nm: Yellow-Green ~600 nm: Orange ~700 nm: Red (longer wavelengths like red are absorbed by chlorophyll but used less efficiently for photosynthesis compared to blue light). 4. The 3 Different Pigments in Photosynthesis There are three main types of pigments involved in photosynthesis: Chlorophyll a: Characterization: The primary pigment involved in photosynthesis. It absorbs light mostly in the red and blue wavelengths (~430-450 nm and ~640-680 nm). Function: Directly involved in the light reactions, where it absorbs photons and starts the process of electron transport. Chlorophyll b: Characterization: An accessory pigment that absorbs light in the blue and red-orange regions (~460-500 nm and ~640-660 nm). Function: Helps chlorophyll a by expanding the absorption spectrum and capturing more light energy. Carotenoids (e.g., Beta-carotene): Characterization: Accessory pigments that absorb light in the blue and blue-green wavelengths (~450-480 nm) and appear yellow, orange, or red. Function: Protects chlorophyll by absorbing excess light energy (photoprotection) and transferring energy to chlorophyll. 5. What Wavelengths and Colors are Absorbed and Used in Photosynthesis? Absorbed: Chlorophyll absorbs primarily in the blue (around 430-450 nm) and red (around 640-680 nm) regions of the light spectrum. Why Green?: Chlorophyll reflects and transmits green light (~500-570 nm), which is why leaves appear green to us. The green light is not absorbed efficiently by chlorophyll and is thus reflected, giving leaves their characteristic color. 6. Photosystem, Light-harvesting Complex, Reaction Center, Primary Electron Acceptor – Relate and Explain Photosystem: Definition: A protein-pigment complex in the thylakoid membrane that absorbs light energy and uses it to initiate the process of photosynthesis. Light-harvesting Complex (LHC): Definition: A group of pigments (such as chlorophyll a, chlorophyll b, and carotenoids) that surround the reaction center in the photosystem. They absorb light and transfer energy to the reaction center. Function: Captures light energy and funnels it to the reaction center. Reaction Center: Definition: The part of the photosystem where the energy from light is converted into chemical energy. It contains a pair of chlorophyll a molecules that absorb energy and release excited electrons. Primary Electron Acceptor: Definition: A molecule that accepts the excited electrons from the reaction center, starting the electron transport chain in the light reactions. It is the first step in converting light energy into chemical energy. These components work together in the light reactions: Light energy is absorbed by the light-harvesting complex. This energy is transferred to the reaction center. The reaction center chlorophyll molecules become excited, and an electron is transferred to the primary electron acceptor. The electron is then passed through the electron transport chain, where it eventually helps generate ATP and NADPH. 7. Photosystem II and Photosystem I – Compare and Contrast Photosystem II (PSII): Function: Splits water molecules (photolysis) to release oxygen, protons (H⁺), and electrons. The electrons from water are passed through the electron transport chain to Photosystem I. Key Feature: It is the first photosystem in the light reactions and operates at a wavelength of around 680 nm. Photosystem I (PSI): Function: Absorbs light energy and re-excites electrons, which are used to reduce NADP⁺ to NADPH. Key Feature: Operates at a wavelength of around 700 nm, slightly higher than PSII. Similarities: Both are involved in the light-dependent reactions and contain reaction centers with chlorophyll a. Differences: PSII begins the process by splitting water and producing oxygen. PSI primarily produces NADPH from the excited electrons it receives from PSII. 8. Linear Electron Flow – Process Description Electron Sourcing: The process begins when light excites chlorophyll molecules in Photosystem II. This causes water to split, releasing electrons, protons (H⁺), and O₂. The electrons are passed through the electron transport chain (ETC) to Photosystem I. Energy-Rich Molecules: As electrons travel through the ETC, they provide energy to pump protons into the thylakoid lumen, creating a proton gradient. This gradient is used by ATP synthase to generate ATP. Meanwhile, the electrons in PSI are re-excited by light and used to reduce NADP⁺ to NADPH. Outcome: The process generates both ATP and NADPH, which are used in the Calvin cycle for the synthesis of sugars. 9. Linear vs. Cyclical Electron Flow Linear Electron Flow: Process: Electrons flow from Photosystem II to Photosystem I, ultimately producing both ATP and NADPH. Generates: ATP and NADPH. Cyclical Electron Flow: Process: Electrons from PSI are cycled back through the electron transport chain, without reducing NADP⁺. Instead, they return to PSI to continue the flow of electrons. Generates: More ATP, but no NADPH or oxygen. Difference: Cyclical flow is used when the cell needs more ATP than NADPH, such as in some parts of the Calvin cycle. 10. Cellular Respiration vs. Photosynthesis Similarities: Both involve energy conversion processes. Both produce energy carriers: ATP in both processes, and NADH in respiration and NADPH in photosynthesis. Both processes involve electron transport chains. Differences: Photosynthesis converts light energy into chemical energy (glucose), occurring in chloroplasts. Cellular respiration breaks down glucose to release energy (ATP), occurring in mitochondria. Photosynthesis requires light, whereas cellular respiration does not. The products of photosynthesis (glucose and oxygen) are used as inputs in cellular respiration (glucose and oxygen), while the products of cellular respiration (CO₂ and water) are inputs for photosynthesis. 11. The Calvin Cycle – Major Inputs, Processes, and Outputs Inputs: CO₂ from the atmosphere (fixed into an organic molecule). ATP and NADPH from the light reactions. Major Process of Energy Usage: Carbon Fixation: CO₂ is attached to RuBP (ribulose bisphosphate) by the enzyme RuBisCO. Reduction: ATP and NADPH are used to convert the fixed carbon into a 3-carbon sugar (G3P). Regeneration: Some G3P molecules are used to regenerate RuBP, enabling the cycle to continue. Major Outputs: Glucose or other carbohydrates, which store chemical energy for the plant. 12. Importance of the Molecule RuBisCO (Ribulose Bisphosphate Carboxylase/Oxygenase) Definition: RuBisCO is the enzyme that catalyzes the carbon fixation step in the Calvin cycle, attaching CO₂ to RuBP. Importance: It is the most abundant enzyme on Earth and is crucial for producing the organic molecules necessary for plant growth and, by extension, all life on Earth. Without RuBisCO, plants would not be able to synthesize glucose from CO₂.

Ch 15 - Joint products and byproducts

Bioproduct vocabulary for exam

ALIAS - EXAM More bioproduct vocabulary: oil refineries etc