Grade 8 Science: Cellular Respiration and Photosynthesis PDF

ELICIT Picture This: What Happened Situation 1: The students suddenly feel exhausted during PE class. They realized Situation 2: A plant slowly wilts Situation 3: A house experiences a that they haven't eaten all day. due to lack of sunlight brownout...

ELICIT Picture This: What Happened Situation 1: The students suddenly feel exhausted during PE class. They realized Situation 2: A plant slowly wilts Situation 3: A house experiences a that they haven't eaten all day. due to lack of sunlight brownout caused by a power outage What could be the probable cause of the aforementioned situations? LACK OF: E NE RGY ENGAGE A QUICK ENERGY CHECK  LIFE REQUIRES ENERGY To perform life processes, all living organisms do tremendous amounts of work, even on a microscopic scale. Link to the video: https://youtu.be/d4TJ4NY1IA0?si=EbkY_T2ZKDSljONs  TO PONDER….. 1. How do you think living organisms obtain the energy they need to survive and thrive? 2. Why do we need to breathe in order to stay alive? GRADE 8 SCIENCE TOPIC 1.8 CELLULAR RESPIRATION and TOPIC 1.9 PHOTOSYNTHESIS Ms. Sheila F. Padilla  LEARNING OBJECTIVE/S At the end of the session, you are expected to: 1. describe cellular respiration. 2. identify the stages of cellular respiration; 3. differentiate aerobic from anaerobic respiration; and 4. Cite the importance of cellular respiration in physical activity and physical fitness.  LEARNING OBJECTIVE/S At the end of the session, you are expected to: 1. explain the process of photosynthesis; 2. list the reactants and products of photosynthesis 3. identify the leaf structures that carry out photosynthesis; and 4. cite the importance of photosynthesis. GRADE 8 SCIENCE TOPIC 1.8 CELLULAR RESPIRATION Ms. Sheila F. Padilla  HOW DOES YOUR BODY OBTAIN ENERGY? When food passes through digestive These molecules travel through the Inside the cells, the energy in the system. The food is then broken down bloodstream to the cells of your body. molecules is released. into small molecules. EXPLORE WHAT IS CELLULAR RESPIRATION? It is a complex process by which cells convert the chemical energy stored in organic molecules, such as glucose, into a form that cells can use, known as Adenosine Triphosphate (ATP), the primary energy currency of the cell.  WHAT IS CELLULAR RESPIRATION? It is a complex process by which cells convert the chemical energy stored in organic molecules, such as glucose, into a form that cells can use, known as Adenosine Triphosphate (ATP), the primary energy currency of the cell. REACTANTS PRODUCT  WHAT IS CELLULAR RESPIRATION? REACTANTS PRODUCT no. of atoms  WHAT IS CELLULAR RESPIRATION? REACTANTS PRODUCT no. of molecules  WHAT DOES ATP DO FOR YOU? It supplies YOU with ENERGY!  ENERGY CARRIERS FOUND IN CELLULAR RESPIRATION Adenosine triphosphate Nicotinamide adenine dinucleotide Flavin adenine dinucleotide WHERE DOES CELLULAR RESPIRATION OCCUR? WHERE DOES CELLULAR RESPIRATION OCCUR? CELLULAR RESPIRATION WHAT ARE THE STEPS OF CELLULAR RESPIRATION? splitting of sugar occurs in cytoplasm 2 net ATP, 2 NADH and 2 pyruvic acids are produced occurs whether or not oxygen is present also known as citric acid occurs in matrix of mitochondria 2 net ATP, 6 CO2, 8 NADH and 2 FADH2 are produced requires oxygen main source of ATP production occurs in inner membrane of mitochondria 34 ATP are produced occurs when oxygen is present  Is it a FACT or a BLUFF? React using the thumbs-up emoji 👍 if the statement is correct and react a thumbs-down emoji 👎 if the statement is incorrect. The main source of ATP production occurs in the cytoplasm of cells. inner membrane of mitochondria  TYPES OF CELLULAR RESPIRATION Aerobic Respiration Anaerobic Respiration  What is aerobic Mitochondrion respiration? Oxygen is used to break down respiratory substrates. The main respiratory substrate is glucose which is oxidized to release its energy.  Aerobic Respiration Equation Glucose + Oxygen Carbon Dioxide + Water + Energy released Anaerobic Respiration This happens when there is no oxygen. It is a less efficient process that only produces a small amount of ATP. It produces lactic acid or alcohol as waste. Most organisms require oxygen to respire and live, however some organisms can continue to respire when oxygen runs out. Humans can do this for a short time, resulting in lactic acid building up in our muscles.  Anaerobic Respiration Equations In muscles In yeast Glucose Lactic acid + Energy Glucose Ethanol + Carbon Dioxide + Energy COMMON DIFFERENCE BETWEEN AEROBIC AND ANAEROBIC Aerobic Respiration Anaerobic Respiration performed by eukaryotic cells performed by prokaryotic and eukaryotic cells goes from cytoplasm to mitochondria only in cytoplasm requires oxygen does not require oxygen efficient (38 ATP) inefficient (2 ATP) reactants: glucose and oxygen reactants: glucose product: CO2 and H2O product: lactic acid (animals) ethanol and CO2 (yeast)  Is it a FACT or a BLUFF? React using the thumbs-up emoji 👍 if the statement is correct and react a thumbs-down emoji 👎 if the statement is incorrect. Aerobic respiration happens when there is no oxygen. It is a less efficient process that only produces a small amount of ATP. It produces lactic acid or alcohol as waste. Anaerobic Respiration  AEROBIC VS. ANAEROBIC RESPIRATION Link to the video: https://youtu.be/WsqP1O7388g?si=HbcJlxIL7QStDmON&t=47  Aerobic Respiration Anaerobic Respiration Aerobic respiration requires oxygen. Both processes involve the breakdown of glucose Both result in the production of ATP providing energy to cells. Both are part of cellular respiration.  Aerobic Respiration Anaerobic Respiration Aerobic respiration requires Anaerobic respiration does oxygen. not require oxygen. more efficient and yields more ATP less efficient and yields less ATP Both processes involve the breakdown of produces carbon dioxide and water produces lactic acid or ethanol glucose as by-products and carbon dioxide, depending on Both result in the the organism. production of ATP relatively slower to produce ATP providing energy to generally faster to produce ATP cells. Both are part of used for continuous movement cellular used for short burst movement like like endurance type of exercise respiration. high intensity movement Aerobic Respiration Anaerobic Respiration Releases a relatively large Releases a small amount of amount of energy. energy very quickly. Oxygen is absent or not Oxygen is present. very abundant. Glucose is not completely Glucose is completely oxidized and the products still oxidized. contain energy. GRADE 8 SCIENCE TOPIC 1.9 PHOTOSYNTHESIS Ms. Sheila F. Padilla  LEARNING OBJECTIVE/S At the end of the session, you are expected to: 1. explain the process of photosynthesis; 2. list the reactants and products of photosynthesis 3. identify the leaf structures that carry out photosynthesis; and 4. cite the importance of photosynthesis. TO PONDER…..  LET’S BREAK IT DOWN bread lettuce flour wheat onion plant tomato cheese cow grass beef  LET’S BREAK IT DOWN bread lettuce flour wheat onion plant tomato cheese cow grass beef  HOW ABOUT PLANTS? How can they provide What do they eat? How do they obtain energy to other energy? organisms? PHOTOSYNTHESIS  PHOTOSYNTHESIS the process that converts solar energy into chemical energy that is used by biological systems occurs in plants and some algae 3 major events: 1. Sunlight is converted into chemical energy 2. Water (H2O) is split into oxygen (O2) 3. Carbon dioxide (CO2) is fixed into sugars (C6H12O6)  LEAF STRUCTURE Photosynthesis happens in the chloroplasts. Chloroplasts are full of round flattened discs called thylakoids. A stack of thylakoids is called a granum. Chlorophyll green pigment that harvests light for Chloroplast photosynthesis Stroma is the space inside chloroplasts. PROCESS OF PHOTOSYNTHESIS The plant draws up water through its roots. The leaves take in carbon dioxide from the air. The leaves trap energy from sunlight. The plant uses energy of sunlight to turn water and carbon dioxide into sugars and oxygen. The plant releases oxygen into the air. The plant uses the sugars for growth.  Is it a FACT or a BLUFF? React using the thumbs-up emoji 👍 if the statement is correct and react a thumbs-down emoji 👎 if the statement is incorrect. Plants use energy of sunlight to turn water and carbon dioxide into sugars and oxygen.  IMPORTANCE OF PHOTOSYNTHESIS Food source Provides energy CO2 is maintained at constant level and provides O2  EXPLAIN Case Studies (Group Work) Scan this QR code to access You will be assigned to a breakout room. As the Worksheet. a group, apply your learned concepts to: 1) identify whether the given real-life scenario involves aerobic, anaerobic respiration, or photosynthesis; 2) cite specific clues that lead you to your answer, and 3) explain your reasoning. Link: https://docs.google.com/document/d/1eRBMshg-yxjKRKn2CtsLz-xHlG2w_k5aJ9AwHT936xE/copy EXPLAIN CASE STUDY ANALYSIS Case Study #1: Sprinting Jerry is a sprinter on the high school track team. During a 100-meter dash, Jerry runs as fast as possible for about 10 seconds. After the race, Jerry feels a burning sensation in his leg muscles and has difficulty catching his breath.  CASE STUDY ANALYSIS Case Study #1: Sprinting Jerry is a sprinter on the high school track team. During a 100-meter dash, Jerry runs as fast as possible for about 10 seconds. After the race, Jerry feels a burning sensation in his leg muscles and has difficulty catching his breath. Answer: Anaerobic Respiration  CASE STUDY ANALYSIS Case Study #2: Scuba Diving Liam is an experienced scuba diver. During a deep dive, Liam swims through a coral reef, observing the colorful marine life. After about 30 minutes, Liam begins to feel lightheaded and decides to ascend slowly to the surface.  CASE STUDY ANALYSIS Case Study #2: Scuba Diving Liam is an experienced scuba diver. During a deep dive, Liam swims through a coral reef, observing the colorful marine life. After about 30 minutes, Liam begins to feel lightheaded and decides to ascend slowly to the surface. Answer: Anaerobic Respiration  CASE STUDY ANALYSIS Case Study #3: Gardening Catriona is fond of planting. One day, she noticed that some of her indoor plants are starting to wilt. So, she decided to transfer it where sunlight is available. The next day, she observed that the plant had some growing sprouts and has regained its original color and shine.  CASE STUDY ANALYSIS Case Study #3: Gardening Catriona is fond of planting. One day, she noticed that some of her indoor plants are starting to wilt. So, she decided to transfer it where sunlight is available. The next day, she observed that the plant had some growing sprouts and has regained its original color and shine. Answer: Photosynthesis  CASE STUDY ANALYSIS Case Study #4: Bread Making Samantha is making homemade bread. She mixes flour, water, yeast, and other ingredients in a bowl. Samantha then kneads the dough and places it in a warm oven to bake. As the bread bakes, Samantha notices the dough rising and expanding in the pan.  CASE STUDY ANALYSIS Case Study #4: Bread Making Samantha is making homemade bread. She mixes flour, water, yeast, and other ingredients in a bowl. Samantha then kneads the dough and places it in a warm oven to bake. As the bread bakes, Samantha notices the dough rising and expanding in the pan. Answer: Anaerobic Respiration A QUICK REVIEW: PHOTOSYNTHESIS AND CELLULAR RESPIRATION A QUICK REVIEW: PHOTOSYNTHESIS AND CELLULAR RESPIRATION ELABORATE: SDG 3: GOOD HEALTH AND WELL-BEING Why is cellular respiration important for living organisms? Cellular respiration completes the circle of life. It provides the energy that sustains life, regulates atmospheric gases, supports food webs, and cycles nutrients. ELABORATE: SDG 13 CLIMATE ACTION How can we promote photosynthesis in urban areas with limited green spaces?  LESSON SYNTHESIS Today, you learned that… 1. Cellular respiration is the process which cells take the energy from glucose to function; 2. Cellular respiration includes three main processes — glycolysis, Krebs cycle and electron transport chain; 3. There are two types of respiration: aerobic respiration that takes place in the presence of oxygen, and anaerobic respiration that takes place in the absence of oxygen; and 4. Cellular respiration increases as you increase your exercise intensity.  LESSON SYNTHESIS Today, you learned that… 1. Photosynthesis is a process by which living plant cells combine CO2 and H2O, in the presence of chlorophyll and light energy.; 2. The equation for photosynthesis is: 6 CO2+12 H2O + sunlight → C6H12O6 + 6 H2O + 6 O2 3. Photosynthesis in plants happens in the chloroplasts.; and 4. Photosynthesis is important, not only for plants to manufacture food, but also for other living things and the environment. EVALUATE LEARNING ACTIVITY 1.5 Answer the Learning Activity 1.5 Cellular Respiration and Photosynthesis.  REFERENCES o Hoefnagels, Marielle (2019). Second Edition: General Biology (Books I and II). McGrawHill Education pages 138-169