UNIT I STUDY GUIDE Introduction, Chemistry, and Cells Reading Assignment Chapter 1: Can Science Cure the Common Cold? Introduction to the Scientific Method Chapter 2: Are We Alone in the Universe? Water, Biochemistry, and Cells Chapter 3: Is It Possible to Supplement Your Way to Better Health? Nutrients and Membrane Transport Chapter 4: Fat: How Much Is Right for You? Enzymes, Metabolism, and Cellular Respiration Learning Activities (Non-Graded) See information below. Key Terms 1. Body mass index (BMI) 2. Calorie 3. Cell 4. Homeostasis 5. Hypotheses 6. Metabolism 7. Nutrients 8. Scientific method 9. Species Learning Objectives Upon completion of this unit, students should be able to: 1. Define inductive reasoning and deductive reasoning. 2. Determine how to minimize bias in experimental design. 3. Explain how random assignment in controlled experiments represents a population. 4. Demonstrate the steps of the scientific method to answer everyday problems or questions. 5. Describe the characteristics common to all living organisms. 6. Evaluate ph for various substances. 7. Compare and contrast the macromolecules of life and their importance to living organisms. 8. Explain the basic structure of an atom and the types of bonds atoms can form. 9. Identify the major cell types and cell structures and describe their function(s). 10. Differentiate between saturated and unsaturated fats. 11. Explain the relationship between the amount of calories a person burns and their age and weight. 12. Calculate the BMR, BMI, and caloric burn. 13. Differentiate among the various types of active and passive transport. 14. Evaluate the various diseases that may result due to diet. 15. Analyze nutritional information based on what the body needs to function properly. Written Lecture The first part of this unit includes material from Chapter 1. Chapter 1 provides a basic introduction into biology using something that we are all familiar with: the common cold. This introduction includes insight into how scientists use the scientific method to test hypotheses and perform investigations. In addition, the introduction also includes information that will assist you, as a consumer, evaluate scientific information and make informative decisions, which will help you become a savvier consumer in society. You will learn what sound scientific research is and the importance of basic statistics in scientific research. You will also gain a basic understanding of the various sources of scientific information. The scientific method is what scientists use to answer questions and problems concerning science; however, we each use this method daily to answer and solve real-life questions and problems. We may not realize that we constantly use the scientific method, and we may not consciously make notes of all of the steps; however, we do. Think about the last time you went out, turned the key in your car, and nothing happened. You observed that your car will not start. You then questioned why your car will not start. You made a hypothesis, one of BIO1100, Non-Majors Biology 1
which could be that the battery was dead. You tested your hypothesis by charging your battery or purchasing a new one. You decided to charge your battery, and your car starts with ease. The results suggest that your hypothesis was supported. In the example above, we concluded that our hypothesis was supported by conducting the test once; however, that is not the case in the scientific world. Keep in mind that scientists rarely prove anything beyond a shadow of a doubt. The tests must be replicated by others, numerous times. Once the results are consistent in numerous tests, theories are constructed. A theory in science is different from a theory in everyday life. Aspects only become theories in science if the general scientific community concluded similar results, and it is generally accepted by all. Knowing all of this will help you become savvier consumers in society. After reading the information in chapter 1, you will understand what must occur in sound scientific research. There are numerous marketing claims for products ranging from lawn care to healthcare. Some make claims without conducting sound research. You are now primed with the knowledge you need to know the difference between true science and false claims not supported by science. Chemistry and Cells: Unit I includes three chapters and introduces chemistry and cells. Why do we have to learn about chemistry in a biology course? Living tbeings are just an organized clump of chemicals. Take humans for instance, 96% of the human body is composed of carbon, hydrogen, oxygen, and nitrogen. Where do the chemicals come from? You may have heard the old saying, You are what you eat. The chemicals in our bodies are derived from the foods that we eat. When we eat, we are eating chemicals in the form of carbohydrates, lipids, and proteins. The chemicals in our bodies combine to form molecules. Molecules form organelles, and organelles make up cells. Cells are the smallest living unit. Organisms such as bacteria, archae, many protists, and some fungi are comprised of single cells; however, some protists, most fungi, all plants, and all animals are made up of numerous cells. In humans and some other organisms, cells combine to form tissues, and tissues form organs. Various organs form organ systems and the systems combine to form an organism. Therefore, we have to understand a little bit about chemicals in order to understand living organisms. Living organisms are considered to be biotic, and non-living aspects are considered to be abiotic. The root word bio means life and a as a prefix means not or without. Abiotic and biotic aspects react in environments and ecosystems. Humans cannot survive without water; after all, our bodies are made up of about 60% water. Water is an excellent solvent, facilitates chemical reactions, evaporates slowly, heats up slowly, and is cohesive. Water is considered to be abiotic because it is non-living; however, we must have water to survive. In addition to water, acids, bases, and salts are also abiotic factors important for our survival. When acids and bases react, salts are produced. Acids and bases are measured using a ph scale. Fluctuations in the ph of an environment will influence the living organisms in the environment. Abiotic factors are also influenced by ph changes. Think about what would happen if you dropped hydrochloric acid on your clothes. Plants require a specific soil ph in order to live. If soil becomes too acidic or too basic, plants will die. Could we live without plants? BIO1100, Non-Majors Biology 2
Acids, bases, salts, and water are related to a branch of chemistry called inorganic chemistry. Inorganic molecules do not contain carbon (with the exception of carbon dioxide and carbon monoxide). Organic chemistry deals with large (macromolecules) that do contain carbon. Macromolecules are formed by various chemical bonds, depending upon the number of electrons in the valence shell of the atom. Atoms will form chemical bonds when the valence shell is not full because the atom is unstable. When chemical bonds occur, molecules such as carbohydrates, lipids, proteins, and nucleic acids are formed. Those are the macromolecules of life. All living organisms are made up of at least one cell. Prokaryotic organisms are single-celled organisms, such as bacteria and archae. Prokaryotic cells lack a nucleus, have circular DNA, do not have membrane-bound organelles, and are generally smaller than eukaryotic cells. Eukaryotic cells do contain a nucleus that houses linear DNA, and they do contain membrane-bound organelles. Eukaryotic organisms include protists, fungi, plants, and animals. The organelles that make up a cell are responsible for the function of the cell. Organelles in cells vary depending on the cell type and the organism. A detailed description of all organelles and their functions are located in Chapter 2. As you may have noticed already, life is diverse. Most biologists agree that there are probably around 10 million different species on Earth. Why is there so much diversity? Why are all living organisms not the same? Most scientists agree that diversity is due to evolution. Evolution cannot be proven beyond a shadow of a doubt; however, there is a tremendous amount of research suggesting evolution occurred (and still does), and most scientists agree upon this theory. The literal translation of the word evolution simply means change. Have organisms changed? Are organisms still changing? What drives or forces this change? We will explore these questions in more detail in Unit III: Evolution. Even as diverse as life forms are, all living organisms react with each other in their environment. Humans depend on numerous organisms and non-living factors for survival. We all eat food we have to. We have to acquire and use energy, we have to build our structures, and our cells have to perform functions. None of this could occur if we did not eat; however, what do we really need to function properly? What nutrients ensure optimal health? What is enough? What is too much? Our health is one of our most important concerns. It is actually very simple; eat what we need and only what we need. It seems simple; however, it is more difficult to actually apply. Most people would rather eat chocolate cake instead of an apple. Do we need the chocolate cake? Does chocolate cake have any nutrients that our body can use? The human body has an amazing ability to break foods down and use what it needs. The body disposes of wastes and stores some nutrients and fats for later use. When we ingest too many food sources, we sometimes gain weight or increase the process of health-related issues. If we do not ingest enough of what we need, the body will digest itself in order to attempt to stay alive. Understanding how the body uses various macronutrients; which nutrients are required in large amounts, such as water, carbohydrates, proteins, fats, and micronutrients; and which nutrients are essential in minute amounts, such as vitamins and minerals, for survival will help you understand why your body reacts in the manner it does. In order to gain an even better understanding of how and why your body functions as it does, it is important to understand what we use for energy and how we use it. We must remember that everything in a living organism occurs on the cellular level. Nutrients must be able to pass through the plasma membrane BIO1100, Non-Majors Biology 3
of a cell, and wastes or products made by the cell must be able to pass. Our primary energy source is glucose, which is a sugar. In a process called cellular respiration, sugar and oxygen react inside the cell to synthesize usable energy, ATP. At first glance, it would seem that we would be able to function better if we ate more and had more energy. Actually, this is true; if our bodily functions require more energy, we will need to eat more. The more you do, the more you need. The problem is that we usually put more fuel into our bodies than we need. When this occurs, our body stores the energy for later use in the form of fat. Increases in body fat often result in health-related issues. Again, it is simple; eat what you need. How do we determine what we need? The rate in which we use energy depends upon our basal metabolic rate (BMR). Our BMR depends upon our height, weight, activity, and current health status. Your BMR determines your daily caloric needs. All you need to do is determine how much you need and how much you currently ingest. If the two are equal, your weight will remain stable. In order to determine your BMR specifically, you would have to have expensive tests conducted; however, there are ways of estimating your BMR. In this unit s lab, you will do just that. You will also determine what you are currently eating. You will be able to examine your habits and determine if you are consuming the nutrients your body needs in adequate amounts. This first unit includes a great deal of information about how living organisms and non-living aspects interact. You will learn how to become a more informed consumer, how chemicals relate to life, what nutrients are required for survival, and how to examine your habits and behaviors in an attempt to improve your health and lifestyle. We only have one chance at this life, and the healthier we are, the better. The more we understand just how much we, as humans, rely on other organisms and non-living aspects, the more we will appreciate that our actions and choices not only affect our own body, but they also affect others and the environments. Learning Activities (Non-Graded) Unit I Lab Step 1: Welcome to the first unit of the BIO1100 Introduction to Biology course. In this first unit you will consider the importance of science and biology in your everyday life. You will investigate the importance of water in everyday life and consider the impact of nutrients and fat on human health. This laboratory assignment supports the following learning objectives: 1. Define inductive reasoning and deductive reasoning. 2. Determine how to minimize bias in experimental design. 3. Explain how random assignment in controlled experiments represents a population. 4. Demonstrate the steps of the scientific method to answer everyday problems or questions. 5. Describe the characteristics common to all living organisms. 6. Evaluate ph for various substances. 7. Compare and contrast the macromolecules of life and their importance to living organisms. 8. Explain the basic structure of an atom and the types of bonds atoms can form. 9. Identify the major cell types and cell structures and describe their function(s). BIO1100, Non-Majors Biology 4
10. Differentiate between saturated and unsaturated fats. 11. Explain the relationship between the amount of calories a person burns and their age and weight. 12. Calculate the BMR, BMI and caloric burn. 13. Differentiate among the various types of active and passive transport. 14. Evaluate the various diseases that may result due to diet. 15. Analyze nutritional information based on what the body needs to function properly. The laboratory assignment consists of three steps which include: a pre-test, content review, and activities and tutorials. These steps will support your learning of the Unit I content as well as explore the major themes and topics. The laboratory assignment will take several hours and can be completed over a few days. Before you begin the unit, complete the following activities to familiarize yourself with MasteringBiology. Pay particular attention to how to navigate the system, progress through the exercises and enter correct answers. Step 2: Content review. In Unit I you have read Chapters 1, 2, 3, and 4. Open and review the linked topical PowerPoint presentations for each chapter for additional review. Chapter 1: Can Science Cure the Common Cold? Introduction to the Scientific Method - Topical PowerPoint Chapter 2: Are We Alone in the Universe? Water, Biochemistry, and Cells - Topical PowerPoint Chapter 3: Is it Possible to Supplement Your Way to Better Health? Nutrients and Membrane Transport - Topical PowerPoint Chapter 4: Fat: How Much is Right for You? Enzymes, Metabolism and Cellular Respiration - Topical PowerPoint Step 3: Activities and Tutorials. Complete the following activities and tutorials within MasteringBiology. Non-graded Learning Activities are provided to aid students in their course of study. You do not have to submit them. If you have questions, contact your instructor for further guidance and information. BIO1100, Non-Majors Biology 5