WELCOME TO BIOLOGY 112 n Biology is about

WELCOME TO BIOLOGY 112! n Biology is about making observations of living things n What observations can you make about this cartoon? 1

Admin: • Pass outline of notes and syllabus • Go over syllabus Resources on my web site: Lectures Outlines/notes n Homework/extra credit assignments n Review Materials, Objectives n Syllabus (link on main lecture page) n Prelabs are also on my lab web site. n 2

This Class is HARD! n n n Don’t procrastinate Try to study every night Details matter You’ll need to know all this stuff for micro & A&P Ask me if you have questions 3

General Info FOOD: ok in lecture room (as long as it’s quiet); NONE allowed in lab n PHONES: please turn it off; if you need to make / take a call, be respectful and go outside. Penalty if it rings a 2 nd time! n IN GENERAL: be respectful of everyone in the class n 4

Chapter 1: Why Study Biology? Biology: scientific study of life n Important to study and understand life in a scientific way n ¨ Awareness and appreciation of life ¨ Important in decisions of life ¨ Issues dealing with biology arise daily 5

Characteristics of Life • What things in this picture are living? • What things are nonliving? 6

Characteristics of Life Bacteria Is it living? 7

Characteristics of all living things n What are some characteristics that are shared by all living things but NOT by nonliving things? 8

Characteristics of all living things 1. 2. 3. 4. 5. 6. 7. CELLULAR ORGANIZATION METABOLISM HOMEOSTASIS GROWTH REPRODUCTION HEREDITY EVOLUTION n Today and through the term, we’ll be discussing these properties of life 9

1 - CELLULAR ORGANIZATION Living things are composed of CELLS n Self-contained living units n Unicellular (single cell) n Multicellular (many cells) n 10

Cells/organisms are highly Organized Humans have organ and tissue systems Complex function n Organization is required for function n Even bacteria have organization 11

Characteristics of life 2. Metabolism All the chemical reactions involving the energy and materials acquired and converted to another form by an organism. ¨ Living Things Acquire/Use Materials and Energy from their Environment and Convert them into useful products.

2 - METABOLISM n n n Collect energy from their environment and use it to grow and develop Energy of sunlight – Photosynthesis Energy from other living organisms – Cellular Respiration 13

Metabolism examples PHOTOSYNTHESIS MOVEMENT 14

Thru Metabolism Life Responds to the Environment n n n Energy gives the organism the ability to respond to environmental stimuli This response involves metabolism Many organisms have multiple senses ¨ Smell, hear, taste, touch, and see 15

Response to Environment n Senses often different than a human’s ¨ Ultraviolet/infrared light ¨ Electrical/ultrasonic fields ¨ Magnetic fields 16

Response to Environment n Senses often different than a human’s ¨ Detection of chemicals (flies/insects) n This response involves metabolism and may change the metabolism of the cell 17

Characteristics of life 3. Homeostasis Life Actively Maintains its Structure and its Internal Environment. ¨ Organisms respond to env changes to keep their internal operating conditions within tolerable limits, else they …

3 - HOMEOSTASIS n Ability of an organism to keep internal environment of cell or organism relatively constant compared to outside environment 19

HOMEOSTASIS n n Uses Regulation to keep the internal environment of cell or organism relatively constant compared to outside environment Regulation and homeostasis are very similar 20

Regulation n n Done in various ways. Example, we keep our internal environment relatively constant in our glucose levels by either releasing or storing glucose. 21

-Regulation PLANT CARBON DIOXIDE - STOMATA ANIMAL TEMPERATURE - BEHAVIORS 22

4 - Growth and Development n DNA as a blueprint ¨ Organisms grow and propagate themselves ¨ Organisms develop and grow in complexity 23

Growth and Development (3) Living things grow and develop 24

5 - Reproduction n Living organisms reproduce or replicate themselves 25

Reproduction EGG AND SPERM POLLEN, FLOWERS, SEEDS 26

6 - Heredity n Genetic material (DNA) is passed from parents to offspring 27

7 - Evolve n n Mistakes are made in replicating DNA Causing the characteristics of a population to change 28

Last 4 Characteristics of life: Living Things Grow, 5. Reproduce 6. Using DNA (Heredity) 7. and have the Capacity to Change & Evolve DNA -deoxyribonucleic acid. . . molecule encoding for life. DNA is 4. inherited. . . offspring from its parent(s). DNA. . . instructions for all traits, proteins and RNA. Errors occur in replicating DNA overtime Life has been around for 3. 8 billion years. . . lot of time for new variants t. . and better use their environment. Evolution is a change in a population over time occurring mainly from mutation and natural selection. These changes. . . DNA.

In life’s hierarchy of organization, new properties emerge at each level n Life’s levels of organization define the scope of biology Life emerges through organization of various levels – Each level is built from one or more lower levels – With addition of each new level, novel properties emerge –

Biosphere Life’s Hierarchy Ecosystem Community Population Organism Brown pelican Organ system Organ Tissue Atom Nucleus Cell Organelle Molecule

Biosphere Ecosystem Florida coast Community All organisms on the Florida coast Population Group of brown pelicans Organism Brown pelican Life’s Hierarchy

Organism Brown pelican Spinal cord Nerve Organ system Nervous system Brain Life’s Hierarchy Organ Brain Tissue Nervous tissue Atom Cell Nerve cell Nucleus Organelle Nucleus Molecule DNA

Organization of Life ¨ Atoms n Smallest unit of elements* ¨ Molecules n Smallest unit of compounds* ¨ Cells n Smallest unit of life ¨ Populations n The unit that changes with time * Will be discussed in chemistry 34

Species vs Population –cats in an area Species –all kitty cats 35

What’s a species? n A group of organisms that can interbreed and produce fertile offspring 36

Why “fertile offspring”? n The mule ¨ horse-donkey hybrid ¨ Cannot breed 37

Levels of Classification n n Scientists way of making sense of over 1. 8 million different types of organisms Group similar organisms into ever bigger groups 38

Levels of Linnaean Hierarchy n n Seven levels Add Domains for eight 39

Levels of Classification n How do we classify all these organisms?

Levels of Classification n How do we classify all these organisms? Single-celled prokaryotes Single- or multi -celled eukaryotes

Classification: The Tree of Life n The Tree of Life is based on DNA sequence similarity 42

Evolve vs Grow n EVOLVE: Species change over generations n GROW: Individuals change over organism’s lifespan 43

Father of Evolution 44

Darwin’s Theory of Natural Selection n Individuals in a population vary in their traits 45

Darwin’s Theory of Natural Selection n n Individuals in a population vary in their traits More offspring are produced than the environment can support 46

Darwin’s Theory of Natural Selection n Individuals in a population vary in their traits More offspring are produced than the environment can support Better-suited individuals reproduce more 47

Natural Selection Overview n Natural selection occurs as heritable variation responds to environmental factors that favor the reproductive success of some individuals over others 48

Current Example of Evolution – Multidrug-resistant Bacteria Evolved. R to Penicillin obtained from a Mold Staphylococcus 49

Biological Diversity Theory of Evolution explains the diversity seen in the natural world 50

Review of the Properties of Life n n n CELLULAR ORGANIZATION (or ORDER) HOMEOSTASIS or REGULATION GROWTH and DEVELOPMENT n n METABOLISM and/or RESPONSE TO ENVIRONMENT REPRODUCTION with DNA HEREDITY (DNA) EVOLUTION 51

-Review of Cells PLANT CELL ANIMAL CELL 52

-Review of Cells CELL SIZE COMPARISON • Animal • Plant • Bacteria • Noncellular viruses 53

SUMMARY All living things share certain characteristics n The differences between living and nonliving are not clear-cut n Levels of organization define biology and n Different properties emerge at each level n 54

SUMMARY All living things share certain characteristics n The differences between living and nonliving are not clear-cut n Living things are classified into domains and kingdoms n Levels of organization defines biology n 55

The Scientific Method: How Scientists Think Deductive Reasoning n Makes a decision by applying a general principle Inductive Reasoning n Makes a general principle by applying many different specific observations Should I touch this piece of metal? 56

Two Approaches to Science 1. n n n DISCOVERY SCIENCE No experiments Based on observations Inductive reasoning – general principles derived from large number of specific observations EXAMPLE: All living things are composed of cells 57

Two Approaches to Science 1. n n n HYPOTHESIS-BASED SCIENCE Involves carefully planned experiments Based on observations Deductive reasoning – takes a general statement and extrapolates specific results we would expect 58

How Scientists Think Biology is a science, and all science must have merit, or it will not be accepted. . How do scientists ensure that their facts and theories are accepted by others? . . . the scientific method! n Pasteur's hypothesis testing of spontaneous generation. n 59

The Scientific Method 1. make an observation. Observe some aspect of nature and ask a question about it. . 2. develop a hypotheses about a possible answer or solution to your question. 3. use hypotheses to make a prediction about. . . observe next, devise. . . test your prediction with an experiment. 4. if results do not confirm the hypothesis, discard or modify it. Otherwise, repeat devise new tests to confirm your results. 5. make a conclusion by analyzing. . . Report your findings.

The Scientific Method hypotheses -an educated guess about an observation. . not been tested. n theory -in common English, an explanation for an observation or an educated guess. n scientific theory -an explanation that has not been disproved after years of rigorous testing. . used. . . to explain additional observations. Evolution. . . main theory underlying all biology. n

Example n n OBSERVATION: Millions of fish are periodically killed in mysterious dieoffs in the mid-Atlantic. Their bodies are covered in bleeding sores. QUESTION: What is causing this to happen to these fish? 62

Hypothesis n. Example Hypothesis: n A microscopic protist, Pfiesteria, was killing ¨ A testable explanation that the fish explains an observation What is an hypothesis? ¨ Addresses the question which came from the observation What is your hypothesis about the fish die-offs? 63

Predictions n n n Based on the hypothesis Can be tested Example—two testable predictions Pfiesteria would be found in larger numbers during the die-offs ¨ Pfiesteria would be capable of killing healthy fish ¨ 64

Experiments Designed to test the predictions n Results either support or refute hypothesis n An experiment should only test ONE thing (the variable) n Everything else should be the same (constant) n You need something to compare to (control) n 65

Experiments n Results from testing ¨ Pfiesteria was found where fish were dying ¨ Pfiesteria quickly killed the fish in the laboratory ¨ Pfiesteria infect and kill fish cells 66

Conclusion Does the evidence presented support or refute the Pfiesteria hypothesis? n Note in science, we can disprove a hypothesis (refute it), but we can never prove it. n A disproven hypothesis can be revised to include new information. n 67

The Scientific Process does not… Make moral judgments n Prove or disprove faith-based beliefs n Determine personal aesthetic values n Produce a FINAL answer because it is always open to more testing. You can only support a hypothesis, not prove it. n 68

Experiment Does Brand X fertilizer really help my plants grow? W AT ER W FE AT RT ER IL + IZ ER 69

Controlled Experiments Have: n TWO GROUPS ¨ Experimental group ¨ Control group INDEPENDENT VARIABLE – the one thing in the experiment different between the two groups. What you change in your experiment n CONSTANT Variables – the things that are the same between the groups n 70

Controlled Experiment Control Group W AT ER Experimental Group W FE AT RT ER IL + IZ ER INDEPENDENT VARIABLE? CONSTANTS? 71

Controlled Experiments DEPENDENT VARIABLE – the thing (or things) in the experiment that you are measuring n The dependent variable DEPENDS on the independent variable n 72

Control Group W AT ER Experimental Group W FE AT RT ER IL + IZ ER DEPENDENT VARIABLE? HINT: the dependent variable depends on the independent variable 73

Scientific Method - Discussion Problems Find a partner n Discuss each scenario with your partner, then share with the group n Scientific Method problems n 74