Second Grade Time Test!!!

LESSON 4. Cellular Respiration • Define cellular respiration • Identify the stages of clan respiration You have just learned how the energy from the sun is captured, processed, and stored in the form of glucose. Cellular respiration, another important life process, is the means by which cells release the stored energy in glucose to make adenosine triphosphate (ATP). The primary goal of this life process is to convert stored energy into usable form, such as ATP, for the cells to carry out their functions. Cellular respiration involves several chemical reactions. The reactions can be summed up in the following equation: C6 H12 O6 + 602 ----- 6 CO₂ +6H₂O + ATP Glucose oxygen carbon dioxide water energy Aerobic respiration reactions, or cellular respiration that takes place in the presence of oxygen, can be grouped into three stages glycolysis, Krebs cycle, and electron transport chain (ETC). Stage 1: Glycolysis Glycolysis is the process that breaks down one molecule of 6-C glucose into 3-C pyruvates or pyruvic acids. It also releases four molecules of ATP. This process occurs in the cytoplasm of the cell. The following is the step-by-step process of glycolysis. Take note that several enzymes are involved in this process. 1. The first step of glycolysis requires energy. It can only proceed when the two ATP molecules donate energy to the glucose by transferring a phosphate group with the help of an enzyme, producing glucose 6-phosphate 2. Then, a specific enzyme promotes the rearrangement of the atoms, producing the fructose 6-phosphate. 3. The action of the enzyme in step 2 promotes the transfer of a phosphate group from another ATP molecule, forming fructose 1,6-bisphosphate. 4. The resulting fructose 1,6-bisphosphate molecules, with the help of another enzyme, splits into two molecules, each with three carbon backbones. These two sugars are dihydroxyacetone phosphate and glyceraldehyde 3-phosphate. 5. Another important enzyme then rapidly interconverts the molecules of dihydro-xyacetone phosphate and glyceraldehyde 3-phosphate. This produces two molecules of glyceraldehyde 3-phosphate or 3-phosphoglyceraldehyde (PGAL) 6. The succeeding step involves another enzyme-mediated action. The hydrogen (H) from PGAL is transferred to the oxidizing agent, nicotinamide adenine dinucleotide (NAD), which forms NADH. A phosphate (P) is also added from the cytosol of the cell to oxidize the two molecules of PGAL, forming two 1.3-bisphosphoglycerate. 7. A phosphate (P) from 1,3-biphosphoglycerate is transferred to ADP to form ATP. This happens for each of the two 1,3-bisphosphoglycerate. resulting to a yield of two ATP and two 3-phosphoglycerate molecules. 8. A phosphate is transferred from 3-phosphoglycerate molecules from the third carbon to the second carbon, forming 2-phosphoglycerate molecules A hydrogen atom and a hydroxyl ((OH) group is released, which then combines to form water (H2O). The removal of H2O from 2-phosphoglycerate results in the formation of 2- phosphoglycerate molecules. 9. A hydrogen atom and a hydroxyl ((OH) group is released, which then combines to form water (H2O). The removal of H2O from 2-phosphoglycerate results in the formation of two phosphoenolpyruvic acid (PEP) 10. Phosphate (P) from PEP is transferred to ADP (and forms ATP) and the final product, pyruvic acid. This reaction yields two molecules of pyruvic acid and two ATP molecules In summary, a single glucose molecule that undergoes the process of glycolysis produces two molecules of pyruvic acid, four molecules of ATP, two molecules of NADEL and two molecules of H.O. However, only two molecules of ATP are counted as net products since two molecules of ATP are spent throughout the process. Stage II: Krebs Cycle The Krebs cycle, named after its proponent Sir Hans Adolf Krebs, is a cyclical series of enzyme-controlled reactions. This stage of cellular respiration occurs in the matrix of the mitochondria. It is sometimes. called the citric acid cycle (CAC) since it produces citric acid. Citric acid contains three carboxyl (COOH) groups; hence, it is also called the tricarboxylic acid cycle (TCA). This requires the pyruvic acids produced during glycolysis. The main function of this cycle is to produce high-energy-yielding molecules, namely, NADH and flavin adenine dinucleotide (FADH) that will later on be used in the electron transport chain reaction. Figure 6-7. Summary of glycolysis and corresponding products in each reaction presented (See Appendix F on page 285 for an enlarged and complete version of the image.) An initial process is needed for the Krebs cycle to begin. As a pyruvate molecule from glycolysis enters the mitochondrion, it undergoes an important preliminary ate to form acetyl-CoA reaction. Coenzyme-A (COA) combines with pyruvate help of an enzymatic complex. This conversion also produces CO, and NADH. The Krebs cycle is summarized as follows. Take note that several enzymes are involved in this process. 1. The Krebs cycle technically begins when the acetyl-CoA combines with oxaloacetic acid (OAA), a 4-C molecule, to produce citric acid, a 6-C molecule. 2. With the aid of an enzyme, the citric acid now goes through a series of reactions that releases energy. Water molecule is removed from the citric acid and is returned in a different location. The-OH group is repositioned, forming the molecule isocitrate. 3. Isocitrate is then oxidized, forming the a-ketoglutarate, a 5-C molecule. The byproducts of this reaction are NADH and CO, 4 The a-ketoglutarate loses its CO, and a coenzyme-A is added in its place. The decarboxylation occurs with the help of NAD, which then becomes NADH. The resulting molecule is called succinyl-CoA. 5. Succinyl-CoA is converted into succinate. Also in this reaction, a molecule of guanosine triphosphate (GTP) is synthesized. The GTP molecule has similar structure and energy properties to that of ATP and is used by cells the same way. The free phosphate group attacks the succinyl-CoA molecule, which detaches the COA. Then, phosphate is attached to GDP to come up with GTP, similar to the process that occur in ATP synthesis (from ADP to ATP). 6. Two hydrogens are removed from succinate, A molecule of flavin adenine dinucleotide (FAD), a coenzyme similar to NAD, is reduced to FADH, as it takes the hydrogens from the succinate. This reaction produces the fumarate. 7. Fumarate is then converted into malate as the addition of a water molecule is catalyzed. The final reaction is the regeneration of oxaloacetate. The resulting byproduct of this regeneration is NADH Recall that two pyruvate molecules were produced during glycolysis, causing the Krebs cycle to turn twice. Each tuts produces three molecules of NADH, single ATH one FADIH, and the by-product CO, which is exhaled. Stage III: Electron Transport Chain The electron transport chain (ETC) is a series of photon pumps on the inner membrane of the mitochondrion. Electron transport is the last stage of the cellular respiration. In this stage, the energy from NADH and FADH, from the Krebs cycle is transferred to ADP to produce ATP. This process is generally known as oxidative phosphorylation. This energy coupling mechanism in the cell was revealed by the work of Peter stored energy in the form of proton (1) gradient to phosphorylate (add phosphate) ADP and produce ATP. The pumping of hydrogen sons across the inner membrane creates higher concentration ions in the inner membrane than on the outside of the membrane. This chemiosmotic gradient causes the ions to flow back across the membrane where the concentration of ions is lower. ATP synthase lined in the matrix serve as a channel protein, helping the ions to move across the membrane. The chemiosmotic gradient powers the phosphorylation of ADP to ATP, which also occurs in the ATP synthase. After passing through the ETC, the oxygen, being the final hydrogen acceptor, combines with two electrons and two protons, forming a water molecule. Water is a by-product of cellular respiration and is excreted. MINI TEST 6-3 1. Which energy-releasing pathway yields the most ATF in each glucose molecule? 2. Briefly describe the two stages of aerobic respiration that follow glycolysis: (a) Krebs cycle (b) Electron transport chain Anaerobic Respiration Most cells carry out arrobic respiration when oxygen is present. Aerobic respiration is an efficient process that yields a lot of ATP. However, many organisms thrive in mud, marshes, animal gut, canned goods, sewage treatment pond, and deep oceans where oxygen is scarce. Organisms that can live without oxygen are called anaerobes. Cellular respiration that proceeds without the presence of oxygen is called anaerobic respiration. In the event that the oxygen supply becomes low, aerobic cells also perform fermentation and lactic acid fermentation anaerobic pathways. There are two common anaerobic pathways in these cells, alcoholic fermentation and lactic acid fermentation. In alcoholic fermentation, ethyl alcohol and carbon dioxide are produced by some cells using the pyruvate from glycolysis. Each pyruvate molecule is rearranged into acetaldehyde and carbon dioxide, which is eventually released. NADII gives up electrons to acetaldehyde to form ethanol Fermentation is widely used in the industry. Yeast, a fungus used in making bread. can undergo anaerobic respiration. Bakers aux sugar, flour, water, and yeast to form the bread dough. The dough rises due to the carbon dioxide and alcohol released by the yeast cells trapped in air bubbles. Beer and wine manufacturers, we yeast to ferment the sugars in wheat and grape juice, forming alcoholic beverages such as beer and wine. In some cells, glycolysis produces two pyruvates, two NADH molecules, and two ATP molecules. Pyruvate itself becomes the final acceptor of the electrons from the NADH that produces the final product: lactate. Oftentimes, this product is called lactic acid. Human skeletal muscles can carry out fermentation when the blood cannot supply the cells with adequate oxygen during strenuous activities. When lactic acid builds up in the muscles, fatigue, burning sensation, and cramps result. Lactic acid will continue to build up until there is adequate supply of oxygen. Lactic acid is then converted back into pyruvate in the liver. Muscles also restore normal functions. Have you ever wondered why milk or cream turns sour after some time? Bacterial cells that undergo fermentation are responsible in producing lactate that turns the milk sour. These bacteria are used in manufacturing yogurt and sour milk products. Fermentation pathways do not breakdown and utilize the glucose completely. ATP is no longer produced beyond the process of glycolysis. Thus, energy produced is just enough for some single-celled organisms, or the energy can only be used by multicellular organisms for a short period.

Telling Time - Second Grade

Teacher: Good morning, class! Welcome to the second grade. How was your summer vacation? Timmy: It was fun. I went to summer camp with Sam. Timmy: But summer vacation is finished. No more swimming at the beach and making sandcastles. Teacher: Yes, it’s time to study. Timmy: What will we learn in the second grade? Teacher: We will learn Math, Science, and many other things. Cindy: Will we learn French? My favorite class is French. Teacher: Yes, you will have French lessons with Ms. Martin.

Comprehension questions multiple choice for 5th grade English as a second language learners in hong kong on this text " My name is Humpty Dumpty this was my favorite spot high up on the wall I know it's an odd place for an egg to be but I loved being so close to the birds then one day I fell I'm sort of famous for that part folks called it the great fall which sounds a little grand it was just an accident but it changed my life fortunately all the king's men managed to put me back together well most of me there were some parts that couldn't be healed with bandages and glue after that day I became afraid of heights I was so scared that it kept me from enjoying some of my favorite things I walked past the wall every day I would think about climbing that ladder again I really missed the birds and being high above the city but I could never do it again because I knew that accidents can happen I eventually settled for watching the birds from the ground it wasn't the same but it was better than nothing then one day an idea flew by making planes was harder than I thought it was easy to get cuts and scratches but day after day I kept trying and trying until I got it just right my plane was perfect and it flew like nothing could stop it I hadn't felt that happy in a long time it wasn't the same as being up in the sky with the birds but it was close enough unfortunately accidents happen they always do I almost walked away again but then I thought about all the times I'd spent working on my plane and all the other things I'd missed I decided I was going to climb that wall but higher I got the more nervous I felt I didn't want to admit it I was terrified I didn't look up I didn't look down I just kept climbing one step at a time until I was no longer afraid maybe now you won't think of me as that egg who was famous for falling hopefully you'll remember me as the egg who got back up and learned how to fly life begins when you get back up"

Comprehension questions multiple choice for 4th grade English as a second language learners in hong kong on this text " My name is Humpty Dumpty this was my favorite spot high up on the wall I know it's an odd place for an egg to be but I loved being so close to the birds then one day I fell I'm sort of famous for that part folks called it the great fall which sounds a little grand it was just an accident but it changed my life fortunately all the king's men managed to put me back together well most of me there were some parts that couldn't be healed with bandages and glue after that day I became afraid of heights I was so scared that it kept me from enjoying some of my favorite things I walked past the wall every day I would think about climbing that ladder again I really missed the birds and being high above the city but I could never do it again because I knew that accidents can happen I eventually settled for watching the birds from the ground it wasn't the same but it was better than nothing then one day an idea flew by making planes was harder than I thought it was easy to get cuts and scratches but day after day I kept trying and trying until I got it just right my plane was perfect and it flew like nothing could stop it I hadn't felt that happy in a long time it wasn't the same as being up in the sky with the birds but it was close enough unfortunately accidents happen they always do I almost walked away again but then I thought about all the times I'd spent working on my plane and all the other things I'd missed I decided I was going to climb that wall but higher I got the more nervous I felt I didn't want to admit it I was terrified I didn't look up I didn't look down I just kept climbing one step at a time until I was no longer afraid maybe now you won't think of me as that egg who was famous for falling hopefully you'll remember me as the egg who got back up and learned how to fly life begins when you get back up"

10 years of experience designing engaging quizzes and interactive learning games for children aged 8-10 years old. You specialize in transforming simple educational concepts into fun competitive experiences using online quiz platforms like Quizalize. Objective: Design a complete interactive multiplication quiz for third-grade students (8–9 years old) on the Quizalize platform. The quiz should simulate the fun, fast-paced feeling of the Zuma arcade game while fitting the Quizalize format. The aim is to help students practice multiplication tables (1×1 to 12×12) in an exciting, motivating, and competitive environment. Instructions: Structure: Design at least 40 multiplication questions. Questions should appear in increasing difficulty: start from easy (e.g., 2×3, 4×2) and move to harder problems (e.g., 11×12, 9×8). Timing: Set a short time limit for each question (e.g., 10 seconds) to simulate the fast reaction needed in Zuma. Encourage fast thinking and rapid response under time pressure. Answer Choices: Use multiple-choice answers. Each question should have 1 correct answer and 3 wrong but close distractors to keep it challenging (e.g., for 7×6: options 42, 43, 36, 48). Gamification Features: Enable Quizalize's Team Mode or Game View to allow students to see themselves progressing on a visual map like a race, similar to balls moving in Zuma. Set points bonuses for speed and accuracy. Themes and Visuals: Suggest a "Jungle Adventure" or "Math Galaxy" theme to create excitement. Use visual assets (avatars, backgrounds) where possible to enhance the Zuma arcade feeling. Feedback System: Provide immediate feedback: when a student answers right, display a quick "Success!" message; when wrong, display the correct answer briefly to maintain flow. Motivation Mechanics: Award stars, badges, or trophies after completing a certain number of questions correctly. Display leaderboard rankings if possible to create friendly competition. Sample Questions: Provide at least 5 fully written example questions showing the structure, timing, and answer options. Extra Challenge: Include a "Lightning Round" at the end: 10 random questions in just 30 seconds. Important: Keep language child-friendly and motivational. Make sure no question looks too similar to the others to avoid boredom. Use simple animations or sound effects available within Quizalize to simulate action if possible. Take a deep breath and work on this problem step-by-step.

Second Grade

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