What is the correct procedure for turning off the computer?

FORM 2 TERM 1 2022-2023 FINAL TEST

1. What is the Earth's thickest layer? A) Crust C) Outer core B) Mantle D) Inner core 2. What is the condition required for a typhoon to form? A) High vertical wind shear C) Presence of a pre-existing disturbance B) Low sea surface temperatures D) Thick mantle layer 3. A liquid layer that surrounds the inner core. Made up of iron and nickel. A) Outer Core C) Upper Mantle B) Lower Mantle D) Lower Mantle 4. What is the name for a fold that is curved upwards? A) Syncline C) Anticline B) Monocline D) None of the above 5. What is the point on the Earth's surface directly above the focus of an earthquake? A) Seismograph C) Epicenter B) Seismogram D) Focus 6. Which seismic waves can travel through solids, liquids, and gases? A) P waves C) Love waves B) S waves D) Rayleigh waves 7. What term describes the calm center of a typhoon? A) Eyewall C) Tropical storm B) Super typhoon D) Eye 8. What is the Philippine government agency responsible for monitoring and forecasting tropical cyclones? A) PAGASA C) PAR B) PSWS D) NOAA 9. Approximately how many typhoons can enter the Philippine Area of Responsibility per year? A) 10 C) 30 B) 20 D) 40 10. What is the best way to do during an earthquake? A. I will run outside to get away from the shaking. B. I will stay indoors and take cover under a sturdy table or desk. C. I will get under a doorway or in a corner. D. I will stay in my bed and hold on to the headboard.

Generate exact multiple choice questions as give below 1. **Which round of negotiations led to the establishment of the World Trade Organization (WTO)?** - (a) Doha Round - (b) Tokyo Round - (c) Uruguay Round - (d) Kennedy Round **Answer:** (c) Uruguay Round 2. **The General Agreement on Tariffs and Trade (GATT) dealt with:** - (a) Goods only - (b) Services only - (c) Intellectual property only - (d) All of the above **Answer:** (a) Goods only 3. **The 'National Treatment' principle means:** - (a) Exported products are treated equally in the domestic market - (b) Imported goods are treated the same as local goods in the domestic market - (c) Exported products should have the same tariff - (d) None of the above **Answer:** (b) Imported goods are treated the same as local goods in the domestic market 4. **'Bound tariff' refers to:** - (a) A limit on tariffs for imports based on WTO commitments - (b) The tax rate on all exports - (c) The overall cost of tariffs - (d) A tariff-free trade condition **Answer:** (a) A limit on tariffs for imports based on WTO commitments 5. **The Most-Favoured Nation (MFN) principle ensures:** - (a) Equal treatment for all WTO members - (b) Only certain countries receive benefits - (c) Tariffs are raised annually - (d) One country is favored over others **Answer:** (a) Equal treatment for all WTO members 6. **The Agreement on Agriculture includes commitments in:** - (a) Market access, domestic support, and export subsidies - (b) Increasing crop yield and technology access - (c) Subsidizing imports only - (d) Agricultural tariffs only **Answer:** (a) Market access, domestic support, and export subsidies 7. **Which agreement replaced the Multi-Fiber Arrangement (MFA)?** - (a) Agreement on Textiles and Clothing - (b) Agreement on Agriculture - (c) TRIPS Agreement - (d) Technical Barriers to Trade Agreement **Answer:** (a) Agreement on Textiles and Clothing 8. **The WTO's TRIPS Agreement pertains to:** - (a) Agricultural products - (b) Intellectual property rights - (c) Investment measures - (d) Customs valuation **Answer:** (b) Intellectual property rights 9. **The Doha Round primarily focuses on:** - (a) Tariffs on manufactured goods - (b) Trade in agricultural goods - (c) Technology trade - (d) Intellectual property in medicine **Answer:** (b) Trade in agricultural goods 10. **The WTO aims to:** - (a) Restrict all trade - (b) Facilitate free and fair trade - (c) Promote monopoly - (d) Limit member negotiations **Answer:** (b) Facilitate free and fair trade 11. **RTAs aim to:** - (a) Block international trade - (b) Reduce trade barriers within a group of countries - (c) Increase tariffs among members - (d) Promote non-trade-related policies **Answer:** (b) Reduce trade barriers within a group of countries 12. **Customs unions require members to:** - (a) Keep individual external tariffs - (b) Impose the same external tariff on non-members - (c) Remove tariffs only temporarily - (d) Avoid any tariffs within the union **Answer:** (b) Impose the same external tariff on non-members 13. **The WTO's highest decision-making body is:** - (a) General Council - (b) Ministerial Conference - (c) TRIPS Council - (d) Dispute Settlement Body **Answer:** (b) Ministerial Conference 14. **Which principle prevents discrimination between WTO members?** - (a) MFN - (b) National Treatment - (c) Market Access - (d) Subsidy Reduction **Answer:** (a) MFN 15. **A common market involves:** - (a) A shared currency - (b) Free movement of goods, services, and factors of production - (c) Only trade agreements for goods - (d) No tariffs on agriculture **Answer:** (b) Free movement of goods, services, and factors of production 16. **The Agreement on Subsidies and Countervailing Measures addresses:** - (a) Trade in textiles - (b) Subsidies that distort trade - (c) All intellectual property laws - (d) Agricultural trade only **Answer:** (b) Subsidies that distort trade 17. **The WTO's TRIMs Agreement regulates:** - (a) Investments - (b) Trade in goods - (c) Trade in services - (d) Agricultural products **Answer:** (a) Investments 18. **The primary goal of the WTO's SPS Agreement is:** - (a) To allow subsidies on food exports - (b) To prevent arbitrary sanitary restrictions on trade - (c) To regulate intellectual property - (d) To impose environmental standards **Answer:** (b) To prevent arbitrary sanitary restrictions on trade 19. **A trading bloc is:** - (a) A group of countries with no trade agreements - (b) A group of countries that may have a common external tariff - (c) Only formed by countries from the same continent - (d) An agreement that restricts all trade **Answer:** (b) A group of countries that may have a common external tariff 20. **The GATT was succeeded by the WTO because:** - (a) GATT was only for developed countries - (b) WTO covers more areas like services and intellectual property - (c) GATT was non-binding - (d) WTO allows subsidies for agriculture **Answer:** (b) WTO covers more areas like services and intellectual property Certainly! Here are an additional 30 multiple-choice questions based on the document content, with answers provided after each question. --- ### Additional Questions and Answers 21. **The WTO’s Agreement on Technical Barriers to Trade (TBT) seeks to:** - (a) Restrict imports to a minimum - (b) Prevent standards from becoming unnecessary trade barriers - (c) Allow countries to set any standard for goods - (d) Promote only national standards for products **Answer:** (b) Prevent standards from becoming unnecessary trade barriers 22. **The Trade Policy Review Mechanism (TPRM) is designed to:** - (a) Impose tariffs on certain goods - (b) Regularly review and assess national trade policies - (c) Regulate customs duties globally - (d) Control intellectual property rights **Answer:** (b) Regularly review and assess national trade policies 23. **The principle of “progressive liberalization” means that:** - (a) Trade barriers are reduced gradually over time - (b) All tariffs are removed immediately - (c) Only developed countries reduce trade barriers - (d) No commitments are required from developing countries **Answer:** (a) Trade barriers are reduced gradually over time 24. **Which council oversees the Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS)?** - (a) General Council - (b) Services Council - (c) TRIPS Council - (d) Agriculture Council **Answer:** (c) TRIPS Council 25. **The WTO’s 'Dispute Settlement Body' is responsible for:** - (a) Deciding on national trade policies - (b) Settling trade disputes between member countries - (c) Creating new trade agreements - (d) Setting tariffs for member countries **Answer:** (b) Settling trade disputes between member countries 26. **A customs union differs from a free trade area because it:** - (a) Allows tariffs between member countries - (b) Establishes a common external tariff for non-members - (c) Applies only to services - (d) Imposes import quotas on all goods **Answer:** (b) Establishes a common external tariff for non-members 27. **Which of the following agreements deals with cross-border investments?** - (a) TRIPS - (b) TBT - (c) TRIMs - (d) GATS **Answer:** (c) TRIMs 28. **In a preferential trade agreement, member countries:** - (a) Impose the same tariffs as non-members - (b) Reduce trade barriers for each other only - (c) Apply high tariffs to non-member countries - (d) Have no external trade barriers **Answer:** (b) Reduce trade barriers for each other only 29. **The WTO’s Agreement on Agriculture includes which commitment?** - (a) Export subsidies for all agricultural goods - (b) Reduction of domestic support for farmers - (c) Complete elimination of tariffs on food products - (d) Increase in import quotas on agricultural goods **Answer:** (b) Reduction of domestic support for farmers 30. **The Agreement on Anti-Dumping allows countries to:** - (a) Increase exports by lowering prices - (b) Impose duties on imports sold below fair market value - (c) Eliminate all tariffs on certain goods - (d) Restrict domestic production of certain goods **Answer:** (b) Impose duties on imports sold below fair market value 31. **The main objective of WTO’s “National Treatment” principle is to:** - (a) Prevent imports altogether - (b) Treat foreign goods the same as domestic goods - (c) Impose tariffs on all foreign products - (d) Promote exports **Answer:** (b) Treat foreign goods the same as domestic goods 32. **Which of the following is a major goal of the WTO?** - (a) Ensuring trade restrictions remain high - (b) Promoting international free trade and competition - (c) Limiting access to global markets - (d) Supporting only developed countries **Answer:** (b) Promoting international free trade and competition 33. **An economic and monetary union involves:** - (a) A free trade area only - (b) A common currency among members - (c) No external trade agreements - (d) Different currencies for each member country **Answer:** (b) A common currency among members 34. **The WTO's Ministerial Conference meets:** - (a) Annually - (b) Every two years - (c) Quarterly - (d) Every five years **Answer:** (b) Every two years 35. **The WTO Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS) mandates:** - (a) Free trade for all countries - (b) Uniform intellectual property protection standards - (c) Different IP laws for each country - (d) No IP protection for developing countries **Answer:** (b) Uniform intellectual property protection standards 36. **The WTO principle of 'transparency' requires member countries to:** - (a) Keep trade policies secret - (b) Publicly disclose trade policies and practices - (c) Have identical trade policies - (d) Eliminate tariffs on all goods **Answer:** (b) Publicly disclose trade policies and practices 37. **One of the WTO's objectives in dispute settlement is to:** - (a) Resolve trade disputes peacefully - (b) Impose sanctions on non-members - (c) Regulate global tariffs - (d) Control member states' import quotas **Answer:** (a) Resolve trade disputes peacefully 38. **Under the WTO's Market Access commitment, member countries agree to:** - (a) Allow unrestricted imports - (b) Set maximum tariff levels on imported goods - (c) Ban certain goods from other countries - (d) Only trade with specific countries **Answer:** (b) Set maximum tariff levels on imported goods 39. **GATS, or the General Agreement on Trade in Services, governs trade in:** - (a) Agricultural goods - (b) Intellectual property - (c) Services - (d) Manufactured products **Answer:** (c) Services 40. **The Agreement on Pre-shipment Inspection (PSI) aims to:** - (a) Ensure high tariffs on all imports - (b) Allow for inspection of goods before shipping - (c) Eliminate export taxes - (d) Control intellectual property trade **Answer:** (b) Allow for inspection of goods before shipping 41. **Which of the following agreements aims to harmonize customs valuation?** - (a) Anti-Dumping Agreement - (b) Customs Valuation Agreement - (c) TRIMs Agreement - (d) Agreement on Subsidies **Answer:** (b) Customs Valuation Agreement 42. **A significant aspect of the Doha Round is:** - (a) Reducing tariffs on agricultural products - (b) Restricting intellectual property rights - (c) Eliminating all forms of trade - (d) Blocking services trade agreements **Answer:** (a) Reducing tariffs on agricultural products 43. **The term “dumping” in international trade refers to:** - (a) Exporting goods at prices lower than domestic market prices - (b) Importing goods illegally - (c) Increasing domestic prices - (d) Imposing excessive tariffs **Answer:** (a) Exporting goods at prices lower than domestic market prices 44. **WTO members are expected to follow which key principle in reducing tariffs?** - (a) National Treatment - (b) Progressive Liberalization - (c) Quota System - (d) Non-Discrimination **Answer:** (b) Progressive Liberalization 45. **The WTO aims to promote fair competition by:** - (a) Allowing tariffs as the only form of protection - (b) Supporting MFN and anti-dumping measures - (c) Limiting access to agricultural products - (d) Increasing subsidies **Answer:** (b) Supporting MFN and anti-dumping measures 46. **A plurilateral agreement within the WTO:** - (a) Includes all WTO members - (b) Involves only specific countries with shared interests - (c) Bans all tariffs for members - (d) Imposes global trade restrictions **Answer:** (b) Involves only specific countries with shared interests 47. **Trade facilitation in the WTO context means:** - (a) Making trade faster, cheaper, and more predictable - (b) Increasing tariffs on imports - (c) Eliminating all customs procedures - (d) Restricting trade with non-members **Answer:** (a) Making trade faster, cheaper

Why and How Managers Plan Importance of planning The planing process Benefits of planning Planning and time management Types of PLans used by managers Long term and short term plans Strageic and tactical plans Operational plans Planning Tools and Techiqunes Forecasting Contrigency planning Scenario planning Benchmaking Use of staff planners Implementing Plans to Achive Results Goal setting Goal management Goal alignment Participation and involvement Planning Def: The process of setting objectives and determining how best to accomplish them Planning at Eaton Corporation “Making the hard decision before events force them upon you, an anticipating the future needs of the market before the demand asset itself Objectives and goals Identifity the specific results or desired outcomes that one intends to achieve Plan Def: A statement of action steps to be taken in order to accomplish the objectives (goals) Steps in the planning process: Define your objectives Determine where you stand vis-a-vis objectives Develpo premises reagrdsing future conditions Analyze alternatives and make a plan Implement the plan and evaluate results What are the benefits of planning Improves focus and flexibility Imporves action orteitation Imporves coordination and control Imporves time management Time Managment Personal time management tips Do say “no” to request that distract you form what you should be doing Dont get bogged down inn details that can be addressed later Do screen telephone calls, emails and meeting request Dont let drop in visitors, text messaging use up your time Do prioritize your important and urgent work Dont become calendar bound by letting other control your schedule Do follow priorities; do most important and urgent work first Some 77% of mangers in one survey said that digital age has increased th number of decisions they have to make 43% said there was less time available to make these decisions Types of plans used by Managers What is teh time horizon Long term vs Short term Long term Look three or more years into teh future Short term plans Typically cover one year or less However: the increasing environmental complexity and dynamism of recent years has severely tested the concept of “long-term” planning Plans are subject to frequent revisions Most executives would likely agree that these complexities adn uncertainties challenge how er actually go about planning and how far ahead we can really plan At the very least we can conclude that there is a lot less permanency to long term plans today and that tey are subject to frequent revision Managment reaeracher Eillot Jaques believes tha people vary in their capability to think with different time horizons Types of Plans used by Managers (3 of 5) Strategic plans Set broad, comprehensive and linger term action directions for teh entire organization or major division Vision Clarifies purpose of the organization and what it hopes to be on the future Typical plans Specify how the organizations resources are used to implement strategy Tactical plans in business often take the form of functional plans Functional plans Incidate how different component within the organiztion will help accompnlish the overall strategy Production plans Finacial plans Facilites Plans Logisitc plans Marketing plans Human Resource Plans Operation plans Describe short-term activities to implement strategic plans Policies: Are standing plans that communicate guidelines for decisions Ex: Policies on office romances: The media is quick to report when a top executive or public figures runs into trouble over an office affair. Are there ant policies on office romances? Employer polices on office raltioshiis vary. One survey find teh following: 24% prohibit relationships among employees in the same department 13% prohibit relationships among employees who have the smae supervisor 80% prohibit relationships between supervisors and subordinates 5% have no restrictions on office romances Procedures: Are rules that describe actions to be taken in specific situations Budgets: are single use plans that commit resources to projects or activities Zero based budgets: allocate resources as if each budget were brand new There is no guarantee that any past funding will be renwer. All propsales, old and new, must compete for available funds at teh start of each new budget cycle Forcasting Attempts to predict the future Qualitaive forecasting uses expert opinions Quantitative forecasting uses mathematical models and statiscal aanylsis of historical data dna surveys Contingency planning Identify alternative course of action to take when things go wrong Anticipate changing conditions Contain trigger points to indicate when to activate plan (or a specific course of action) Scenario planning A long term version of contingency planning Identifying alternative future scenarios Plans made for each future scenario Increases organizations flexibility and preparation for future shocks Benchmarking Use of external and internal comparisons to better evaluate current performance Adopting best practices: things people adn organization do that lead to superior performance Staff Planners Experts who assist in all steps of the planning process They help bring focus and expertise to a wide variety of planning tasks Important: Communication between staff planers landline managers is essential for teh success of teh planning process Goal Setting - Always set SMART goal The solution: Goal Aligment Between Team Leader and Team Member Jonintly plan: Set objectives, set standards, choose actions Individually acy: Perform tasks (member), provide support (leader) Jointly control: Review results, discuss implications, renew cycle x4 Collective effort and commitment Participatroy planning Includes in all planning steps that people who will be affected by the plans adn askedd to help implement them Unloacks motivational potential of goal setting Management by objective (MBO) promotes participation Participation increases understanding and acceptance of plan and commitment to success Participatory planning - Number of people involved in teh decision making process Amazon is intensely focused on what it does. It believes in creating tight single-threaded teams, also known as “2 pizza team.” Data and Decision Making What are some of the important competencies managers must have today? Delegate Marketing and technology Manager must have Technological competency Ability to understand new technologies and to use them to their best advantage Information competency Ability to locate, gather, organize and display information for decision-making and problem solving Analytical competency Ability to evaluate and analyze information to make actual decisions and solve real problems What is the difference between Data and Information Data Raw facts and observation Information Data made useful and meaningful for decision-making Important concepts Big data Exists in huge quantities and is difficult to process without sophisticated mathematical and analytical techniques Data production today Bernard Marr is an internationally best-selling author. He helps organizations improve their business performance, use data more intelligently Data mining The process of analyzing data to produce useful information for decision-makers Management Analytics The systematic evaluation and analysis of data to make informed decision Information drives management Bad Data Refers to information that can be erroneous, misleading, and without general formatting The challenge: Can er use the data that is available in the “Big Data” Needs to be valid Can not trust everything out there Being ethical Look at the trends Data is structured and unstructured Data BIg Data = Structured + Unstructured Information Drive Management decision making What are the characteristics of useful information Easy to access If its credible Accurate Characteristics of useful information: Timely High quality Complete Relevant Understandable What about bad data It's not credible Miss information If it is not structured/ organized Bias based on opinions Confusing If its updated Bad data Refers to information that can be erroneous miss What are some examples of Management information system Business intelligence -BI Information systems to extract and report data in organized ways that are useful to decision-makers Executive dashboards Visually update and display key performance metrics (or Key Performance Indicators -KPIs) and information on a real-time basis Information needs in organization External Environment Information exchanges with the external environment Gather intelligence information Provide public information Information needs within the organizations (internal Enviroement) Information exchange within the organization Facilitate decision making Facilitate problem-solving Managers as information processors Continually gather, share and receive information Now as much electronic as it is face-to-face Always on, always connected How many people telecommute at least once a week 70% of people globally work remotely at least once a week, Work at home after covid 19 our forecast Our best estimate it that 25-30% of the workforce will be working form home multiple days a week by the end of 2021 As of 2023, 12.7% of full time employees work from home, while 28.2% work a hybrid model Managers as problem solvers Problem-solving The process of identifying a discrepancy between actual and desired performance and taking action to resolve it Ishikawa Fishbone diagram To identify the cause of problems Decision A choice among possible alternative courses of action Performance threat Something is wrong or has the potential to go wrong Performance opportunity The situation offers the chance for a better future if the right steps are taken Problem-solving approaches or style - from textbook Problem avoiders Inactive in information gathering and solving problems Problem seekers Proactive in anticipation of problems and opportunities and taking appropriate action to gain an advantage Problem solvers Reactive in gathering information and solving problem Managers - can approach problems in a systematic or intuitive manner Systematic thinking approaches problem in rational, step-by-step and analytical fashion Intuitive thinking approaches problems in a flexible and spontaneous fashion Multidimensional thinking- applies both intuitive and systematic thinking Managers face structured and unstructured problems Structure problems Are ones that are familiar, straight forward, and clear with respect to information needs Program decisions apply solutions that are readily available from past experiences to solve structured problems Know how to solve them Familiar Know what we are dealing with Unstructured problems Are ones that are full of ambiguities and information deficiencies Nonprogrammed decisions apply a specific solution to meet the demands of a unique problem Commonly faced by higher-level management Crisis decision making A crisis involves an unexpected problem that can lead to disaster if not resolved quickly and appropriately Ruled for crisis management Figure out what is going on Remember that speed matters Remember that slow counts, too Respect the danger of the unfamiliar Value the skeptic Be ready to “fight fire with fire” Managers make decisions with various amounts of information Certain environment Offers complete information on possible action alternatives and their consequences Risk environment Lacks complete information but offers probabilities of the likely outcomes for possible action alternatives Uncertain environment Lacks so much information that it is difficult to assign probabilities to the likely outcomes of alternative Ex: Certain and uncertain environments: The worldwide Governance Indicators for over 200 countries, comparing distinct environments (Canada-Brazil) Step 1-Identify and define the problem Focuses on information gathering information processing and deliberation Decision objectives should be established What are some common mistakes in definding problems? Common mistakes in defining problems Defining the problem too broadly or too narrowly Focusing on symptoms instead of causes Choosing the wrong problem to deal with Step 2- Generate and Evaluate Alternative Courses of Action Potential solutions are formulated and more information is gathered, data are analyzed, the advantages and disadvantages of alternative solutions are identified Common mistakes: Abandoning the search for alternatives too quickly Step 3- Decide on a preferred course of Action Two different approaches Behavioural model leads to satisficing decisions Classical model les to optimising decisions Behavioural Model Rationality is bounded because: There are limits our thinks capacity Available information (incomplete) Time constraints Step 4-Implement the decision Involves taking action to make sure the solution decided upon becomes a reality Managers need to have the willingness and ability to implement action plans Problems: Lack of participation error should be avoided Step 5 - Evaluate Results Involves comparing actual and desired results The positive and negative consequences of the chosen course of action should be examined If actual results fall short desire results, the manager returns to earlier steps in the decision-making process At all steps, check ethical reasoning Ask these spotlight questions Utility Does teh decision satisfy all constituents or stakeholders Rights Does the description respect the rights and duties of everyone? Justice Is the decision consistent with the canons of justice Caring Is the decision consistent with my responsibilities to care? Issues in decision-making How do errors happen? Heuristics: are strategies for simplifying decision-making Availability Bias: Bases a decision on recent information or events Representativeness bias: Bases a decision on similarity to other situations Anchoring and Adjustment Bias: Bases a decision on incremental adjustment from a prior decision point Framing error: Tring to solve a problem in the context perceived, positive or negative Confirmation Error: Focusing on information that confirms a decision already made Escalating commitment: Continuing a course of action even though it is not working Creative Decision making Creativity is the generation of a novel idea or unique approach that solves a problem or crafts an opportunity Big C: Creativity occurs when extraordinary things are done by exceptional people Little C: Creativity occurs when average people come up with unique ways to deal with daily events and situations The three types of situational creativity drivers Chapter review What are objectives and goals? The specific results or desired outcomes What are the 5 characteristics of great (SMART) goals? Forecasting - Attempts Qualitative forecasting uses options Quantitative forecasting uses mathematical models and statistical analysis of historical data and surveys Scenarios-Oracle’s crystal ball combines qualitative and quantitative methods

What is a Plant Cell? Plant cells are eukaryotic cells that vary in several fundamental factors from other eukaryotic organisms. Both plant and animal cells contain a nucleus along with similar organelles. One of the distinctive aspects of a plant cell is the presence of a cell wall outside the cell membrane. Plant Cell Structure Just like different organs within the body, plant cell structure includes various components known as cell organelles that perform different functions to sustain itself. These organelles include: Cell Wall It is a rigid layer which is composed of polysaccharides cellulose, pectin and hemicellulose. It is located outside the cell membrane. It also comprises glycoproteins and polymers such as lignin, cutin, or suberin. The primary function of the cell wall is to protect and provide structural support to the cell. The plant cell wall is also involved in protecting the cell against mechanical stress and providing form and structure to the cell. It also filters the molecules passing in and out of it. The formation of the cell wall is guided by microtubules. It consists of three layers, namely, primary, secondary and the middle lamella. The primary cell wall is formed by cellulose laid down by enzymes. Cell membrane It is the semi-permeable membrane that is present within the cell wall. It is composed of a thin layer of protein and fat. The cell membrane plays an important role in regulating the entry and exit of specific substances within the cell. For instance, cell membrane keeps toxins from entering inside, while nutrients and essential minerals are transported across. Nucleus The nucleus is a membrane-bound structure that is present only in eukaryotic cells. The vital function of a nucleus is to store DNA or hereditary information required for cell division, metabolism and growth. 1. Nucleolus: It manufactures cells’ protein-producing structures and ribosomes. 2. Nucleopore: Nuclear membrane is perforated with holes called nucleopore that allow proteins and nucleic acids to pass through. Plastids They are membrane-bound organelles that have their own DNA. They are necessary to store starch and to carry out the process of photosynthesis. It is also used in the synthesis of many molecules, which form the building blocks of the cell. Some of the vital types of plastids and their functions are stated below: Leucoplasts They are found in the non-photosynthetic tissue of plants. They are used for the storage of protein, lipid and starch. Chromoplasts They are heterogeneous, colored plastid which is responsible for pigment synthesis and for storage in photosynthetic eukaryotic organisms. Chromoplasts have red-, orange- and yellow-colored pigments which provide color to all ripe fruits and flowers. Central Vacuole It occupies around 30% of the cell’s volume in a mature plant cell. Tonoplast is a membrane that surrounds the central vacuole. The vital function of the central vacuole apart from storage is to sustain turgor pressure against the cell wall. The central vacuole consists of cell sap. It is a mixture of salts, enzymes and other substances. Golgi Apparatus They are found in all eukaryotic cells, which are involved in distributing synthesized macromolecules to various parts of the cell. Ribosomes They are the smallest membrane-bound organelles which comprise RNA and protein. They are the sites for protein synthesis, hence, also referred to as the protein factories of the cell. Mitochondria They are the double-membraned organelles found in the cytoplasm of all eukaryotic cells. They provide energy by breaking down carbohydrate and sugar molecules, hence they are also referred to as the “Powerhouse of the cell.” Lysosome Lysosomes are called suicidal bags as they hold digestive enzymes in an enclosed membrane. They perform the function of cellular waste disposal by digesting worn-out organelles, food particles and foreign bodies in the cell. In plants, the role of lysosomes is undertaken by the vacuoles. Chloroplasts It is an elongated organelle enclosed by phospholipid membrane. The chloroplast is shaped like a disc and the stroma is the fluid within the chloroplast that comprises a circular DNA. Each chloroplast contains a green colored pigment called chlorophyll required for the process of photosynthesis. The chlorophyll absorbs light energy from the sun and uses it to transform carbon dioxide and water into glucose. Structure of Chloroplast Chloroplasts are found in all higher plants. It is oval or biconvex, found within the mesophyll of the plant cell. The size of the chloroplast usually varies between 4-6 µm in diameter and 1-3 µm in thickness. They are double-membrane organelle with the presence of outer, inner and intermembrane space. There are two distinct regions present inside a chloroplast known as the grana and stroma. • Grana are made up of stacks of disc-shaped structures known as thylakoids or lamellae. The granum of the chloroplast consists of chlorophyll pigments and are the functional units of chloroplasts. • Stroma is the homogenous matrix which contains grana and is similar to the cytoplasm in cells in which all the organelles are embedded. Stroma also contains various enzymes, DNA, ribosomes, and other substances. Stroma lamellae function by connecting the stacks of thylakoid sacs or grana. The chloroplast structure consists of the following parts: Membrane Envelope It comprises inner and outer lipid bilayer membranes. The inner membrane separates the stroma from the intermembrane space. Intermembrane Space The space between inner and outer membranes. Thylakoid System (Lamellae) The system is suspended in the stroma. It is a collection of membranous sacs called thylakoids or lamellae. The green colored pigments called chlorophyll are found in the thylakoid membranes. It is the sight for the process of light-dependent reactions of the photosynthesis process. The thylakoids are arranged in stacks known as grana and each granum contains around 10-20 thylakoids. Stroma It is a colorless, alkaline, aqueous, protein-rich fluid present within the inner membrane of the chloroplast present surrounding the grana. Grana Stack of lamellae in plastids is known as grana. These are the sites of conversion of light energy into chemical energy. Chlorophyll It is a green photosynthetic pigment that helps in the process of photosynthesis. Functions of Chloroplast Following are the important chloroplast functions: • The most important function of the chloroplast is to synthesize food by the process of photosynthesis. • Absorbs light energy and converts it into chemical energy. • Chloroplast has a structure called chlorophyll which functions by trapping the solar energy and is used for the synthesis of food in all green plants. • Produces NADPH and molecular oxygen (O 2 ) by photolysis of water. • Produces ATP – Adenosine triphosphate by the process of photosynthesis. • The carbon dioxide (CO2) obtained from the air is used to generate carbon and sugar during the Calvin Cycle or dark reaction of photosynthesis. Mitochondria “Mitochondria are membrane-bound organelles present in the cytoplasm of all eukaryotic cells, that produce adenosine triphosphate (ATP), the main energy molecule used by the cell.” What are Mitochondria? Popularly known as the “Powerhouse of the cell,” mitochondria (singular: mitochondrion) are a double membrane-bound organelle found in most eukaryotic organisms. They are found inside the cytoplasm and essentially function as the cell’s “digestive system.” They play a major role in breaking down nutrients and generating energy-rich molecules for the cell. Many of the biochemical reactions involved in cellular respiration take place within the mitochondria. The term ‘mitochondrion’ is derived from the Greek words “mitos” and “chondrion” which means “thread” and “granules-like”, respectively. It was first described by a German pathologist named Richard Altmann in the year 1890. Structure of Mitochondria • The mitochondrion is a double-membraned, rod-shaped structure found in both plant and animal cell. • Its size ranges from 0.5 to 1.0 micrometers in diameter. • The structure comprises an outer membrane, an inner membrane, and a gel-like material called the matrix. • The outer membrane and the inner membrane are made of proteins and phospholipid layers separated by the intermembrane space. • The outer membrane covers the surface of the mitochondrion and has a large number of special proteins known as porins. Cristae The inner membrane of mitochondria is rather complex in structure. It has many folds that form a layered structure called cristae, and this helps in increasing the surface area inside the organelle. The cristae and the proteins of the inner membrane aid in the production of ATP molecules. The inner mitochondrial membrane is strictly permeable only to oxygen and ATP molecules. A number of chemical reactions take place within the inner membrane of mitochondria. Mitochondrial Matrix The mitochondrial matrix is a viscous fluid that contains a mixture of enzymes and proteins. It also comprises ribosomes, inorganic ions, mitochondrial DNA, nucleotide cofactors, and organic molecules. The enzymes present in the matrix play an important role in the synthesis of ATP molecules. Functions of Mitochondria The most important function of mitochondria is to produce energy through the process of oxidative phosphorylation. It is also involved in the following process: 1. Regulates the metabolic activity of the cell 2. Promotes the growth of new cells and cell multiplication 3. Helps in detoxifying ammonia in the liver cells 4. Plays an important role in apoptosis or programmed cell death 5. Responsible for building certain parts of the blood and various hormones like testosterone and estrogen 6. Helps in maintaining an adequate concentration of calcium ions within the compartments of the cell 7. It is also involved in various cellular activities like cellular differentiation, cell signaling, cell senescence, controlling the cell cycle and in cell growth. Disorders Associated with Mitochondria Any irregularity in the way mitochondria function can directly affect human health, but often, it is difficult to identify because symptoms differ from person to person. Disorders of the mitochondria can be quite severe; in some cases, they can even cause an organ to fail.

Related quizzes

Related quizzes