Lesson 1_Intro to Environmental Science.pptx

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1. Lesson 1: Introduction to Environmental Sciences

2. Learning Objectives At the end of this lesson, students will be able to: Describe the basic chemical and biological foundation of life on Earth Define ecosystem and environmental science Give examples of the interdisciplinary nature of environmental science

3. THE CHEMICAL AND BIOLOGICAL FOUNDATIONS OF LIFE Matter and Energy Atomic Structure Carbon and Hydrocarbons

4. Matter and Energy

5. At its most fundamental level, life is made up of matter. Matter is any substance that occupies space and has mass.

6. Matter may occur in any of three forms: gas, liquid and solid .

7. All three states of matter are represented in our body. Gas - lungs and digestive tract (inhaled air) Solid – hard structures (teeth, bone and ligaments) Liquid – most abundant state of matter in the body (blood and fluids)

8. Energy is a force that has an effect upon matter. It is defined as the capability to do work .

9. All processes in the body are accomplished by energy-requiring changes.

10. Two Major Types of Energy Kinetic Energy – energy of motion Potential Energy – stored energy or energy at rest

11. Atomic Structure

12. An atom is the smallest unit of matter that retains all of the chemical properties of an element, in that they cannot be broken down by natural processes suc h as heating or digestion.

13. The tiny atomic nucleus is in the center of the atom and it contains positively charged particles called protons and neutral, uncharged, particles called neutrons .

14. The second, much larger, region of the atom is a “cloud” of electrons , negatively charged particles that orbit around the nucleus.

15. Protons and neutrons have approximately the same mass, about 1.67 × 10 -24 grams . Scientists arbitrarily define this amount of mass as one atomic mass unit (amu) . Electrons are much smaller in mass than protons, only about 1/1800 of an atomic mass unit , so they do not contribute much to an element’s overall atomic mass.

16.   Charge Mass (amu) Location in atom Proton + 1 1 Nucleus Neutron 1 Nucleus Electron - 1 Orbitals

17. All matter is made up of substances called elements, which have specific chemical and physical properties and cannot be broken down into other substances through ordinary chemical reactions.

18. Each element is designated by its chemical symbol, which is a single capital letter or, when the first letter is already “taken” by another element, a combination of two letters. Some elements follow the English term for the element, such as C for carbon and Ca for calcium. Other elements’ chemical symbols come from their Latin names; for example, the symbol for sodium is Na, which is a short form of  natrium , the Latin word for sodium.

19. There are 118 elements , but only 92 occur naturally. The remaining elements are synthesized in laboratories and are unstable.

20. The number of proton in each atom is a characteristic feature of the element and is called its atomic number. The atomic weight is the mass of all atomic particles within an atom, and is usually represented as the sum of the protons and neutrons in the nucleus.

21. The four elements common to all living organisms are oxygen (O) , carbon (C) , hydrogen (H) , and nitrogen (N) , which together make up about 96% of the human body.

22. Isotopes are different forms of an element that have the same number of protons but a different number of neutrons.

23. Molecules are formed when two or more atoms join together through chemical bonds to form a unit of matter. Example: CO 2 , indicating that this molecule is made up of one carbon atom and two oxygen atoms.

24. Chemical Compounds of the Cell

25. The basic functional unit of life is a cell and all organisms are made up of one or more cells. In the cell, these chemicals are often combined to form larger compounds.

26. Cells are made of many complex molecules called macromolecules , such as proteins, nucleic acids (RNA and DNA), carbohydrates, and lipids.

27. Two Categories of Chemical Compounds in Cells Inorganic Compounds Organic Compounds

28. Inorganic compounds do not contain chains of carbon atoms and are usually held together by ionic bonds. Example: water, salts, acids and bases

29. Organic Compounds typically contains one or more carbon atoms, which are often capable of forming large molecular chains with other carbon atoms. The carbon-based molecules are usually held together by covalent bonds .

30. The macromolecules are a subset of organic molecules that are especially important for life. The fundamental component for all of these macromolecules is carbon .

31. The carbon atom has unique properties that allow it to form covalent bonds with as many as four different atoms, making this versatile element ideal to serve as the basic structural component, or “backbone,” of the macromolecules.

32. Macromolecules/ Biomolecules Carbohydrates Lipids Proteins Nucleic Acids

33. Carbohydrates Group of organic molecules that include the sugar and starches. provide energy to the body, particularly through glucose( C 6 H 12 O 6 ) , a simple sugar that is a component of starch and an ingredient in many staple foods can be represented by the stoichiometric formula (CH 2 O) n , where n is the number of carbons in the molecule. the origin of the term “carbohydrate”: the components are carbon (“carbo”) and the components of water (hence, “hydrate”)

34. Three types of Carbohydrates Monosaccharides – 3 to 7 carbon atoms (glucose, fructose and galactose) Disaccharides – formed when two monosaccharides are joined together (sucrose, lactose, maltose) Polysaccharides – formed when dehydration synthesis combines more than two carbohydrate molecules together (starch)

35. Lipids include fats, oils, and waxes Hydrophobic (“water fearing”, or insoluble in water) molecules that are almost entirely made up of carbon and hydrogen atoms Contribute about 10 – 12% of the total mass of a cell

36. Three Categories Triglycerides Phospholipids Steroids

37. Proteins most abundant organic molecules in the body, which make up about 20% of total body weight have the most diverse range of functions of all macromolecules made up of chains of amino acids (20 amino acids) Primary roles: structural support, transport, movement, metabolism, regulation and communication

38. Nucleic Acids Extremely large organic molecules that contain the information determining the structure and function of the cell. composed of monomers known as nucleotides the most important macromolecules for the continuity of life. They carry the genetic blueprint of a cell and carry instructions for the functioning of the cell. The two main types are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA).

39. Nucleic Acids deoxyribonucleic acid (DNA) Located within the nucleus of a cell and contains the hereditary materials of life called genes ribonucleic acid (RNA) Found in both the nucleus and cytoplasm of the cell.

40. Hydrocarbons are organic molecules consisting entirely of carbon and hydrogen. Example: gas grill (propane), lighter (butane)

41. The Earth is assumed to be about 4.5 billion years old. For that much time, various species of organisms have already emerged and disappeared. However, it is quite ironic how to maintain equilibrium (balance), living organisms are classified in a hierarchical and orderly manner according to their level of complexity.

42. Environmental science is the study of patterns and processes in the natural world and their modification by human activity. This term also refers to a grouping of scientific disciplines that are all concerned with the physical, chemical and biological characteristics of the surroundings in which organisms live.

43. What does an Environmental Scientist do? Environmental scientists conduct research to identify, control, or eliminate sources of pollutants or hazards affecting the environment or public health. Their research typically involves: - Determining data collection methods - Collecting and analyzing air, water, and soil samples - Analyzing environmental data gathered by others - Looking for correlations to human activity - Preparing reports and presentations that explain their findings

44. Major Fields of Study Related to Environmental Science

45. 1. Biology: study of living things (organisms) - Ecology: study of how organisms interact with one another and with their nonliving environment - Botany: study of plants - Zoology: study of animals

46. 2. Chemistry: study of chemicals and their interactions - Biochemistry: study of the chemistry of living things

47. 3. Earth science: study of the planet as a whole and its nonliving systems o Climatology: study of the earth’s atmosphere and climate o Geology: study of the earth’s origin, history, surface, and interior processes o Hydrology: study of the earth’s water resources o Paleontology: study of fossils and ancient life

48. 4. Social sciences: studies of human society o Anthropology: study of human cultures o Demography: study of the characteristics of human populations o Geography: study of the relationships between human populations and the earth’s surface features o Economics: study of the production, distribution, and consumption of goods and services o Political Science: study of the principles, processes, and structure of government and political institutions

49. 5. Humanities: study of the aspects of the human condition not covered by the physical and social sciences o History: study of information and ideas about humanity’s past o Ethics: study of moral values and concepts concerning right and wrong human behavior and responsibilities o Philosophy: study of knowledge and wisdom about the nature of reality, values, and human conduct