Unit1-TheScienceofBiology MS B · 2019. 9. 10. · Test the wire connections . 9/9/19 9...

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Bellringer !  8/26/19 – Jane Goodall !  ! Describe how Jane did discovery science. !  ! How is the way Jane did science different from that of a typical science lab?

! Watch first 12 minutes of Jane documentary

Bellringer !  8/28/19 –Fortune Telling Fish? !  Directions: !  Open your fortune telling fish and put it in your hand and observe

what happens. What does the packaging say this means about your personality?

!  One criteria for scientific thought is that all phenomena have NATURAL causes or explanations.

!  Discuss with your team some natural cause that could explain the fish’s movements.

!  !  WRITING: !  Choose one of the causes your group suggested. !  Write a hypothesis that predicts the cause for the fish’s movements. !  Briefly describe a way you could test your hypothesis.

Bellringer: 9/3/19 -‐ Lab Safety

⚫ 7. As you are watch the UC Lab Safety Video write down 3 lab safety standards presented.

⚫ UCLA Lab Safety Video

Bellringer 9/4/19 –Scien9fic Methods ! Put the following steps in order.

!  Question !  Hypothesis !  Prediction !  Test !  Observation

! What are the key elements to a good hypothesis? ! What are the two outcomes of a scientific test?

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Bellringer: 9/5/19-‐ Variables !  1. What are the 3 Types of variables? Give an example of each using the mimicry (snake) experiment.

!  2. Compare and contrast the two groups in a scientific experiment. Use a Venn diagram to do this.

The Science of Biology

Unit 1

Biology ! Science is a quest to understand nature

!  It includes elements of surprise, challenge and adventure

!  Careful planning, reasoning, persistence, patience, set-backs and tiny steps of progress also mark the path of science

!  In this chapter you will learn how science works and how you can use the process of science to help answer your own questions

Biology ! Biology - the scientific study of LIFE ! Biology blends 2 main forms of scientific exploration:

!  Discovery science !  Mostly about describing nature

!  Hypothesis-based science !  Mostly about explaining nature

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What is Biology? – 5 Unifying Themes Life through photographs

Inquiry and Observation ! At the heart of science is inquiry:

people asking questions about the world around them and seeking answers

!  Why does a house plant grow toward the light?

!  How does it sense the direction of the light?

!  What enables the plant to bend toward the light?

!  What direction would the plant grow in the dark?

Inquiry and Observation ! More that just asking questions.

!  Inquiry - the process of investigation, with a thoughtful question, leading to a search for answers.

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Observations and Data ! The questions that drive scientific inquiry are based

on observations. !  Observation - the use of the senses to gather and

record information about structures or processes. !  Sight !  Sound !  Smell !  Touch !  Taste

Observations and Data ! Recorded observations are call data.

!  Put another way, data are forms of information !  Pencil marks on a door frame recording a child’s height and

growth are data !  Carefully recorded observations in a field journal about

chimpanzee are data !  A chart with the yearly rainfall recorded is data

Observations and Data ! All observations depend on human senses. ! Today’s data is often collected using technology. ! Many times our senses are limited and we need help ! Examples:

!  Telescopes !  Microscopes !  Seismographs !  Scales !  Thermometers !  Etc.

Data Collec9on !  Two types of data: Qualitative and Quantitative

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Data Collec9on Qualitative Data !  Qualitative -‐ descriptions in

words !  QUALITIES !  Ex: Viscous liquid, Brown pigment

Quantitative Data !  Quantitative – numeric

measurements !  QUANTITIES !  Ex: 10 seconds, 30 feet, 98.6° Fahrenheit

Observations and Data ! Data can best support science when it is clearly

organized, consistently recorded and reliable. !  Ex: Charts , graphs, tables

Inferences in Science ! A logical conclusion based on observations is called an

inference. !  A person makes an inference by relating observations to

prior knowledge

Observation + Prior knowledge= inference(logical conclusion)

Inferences in Science ! What do you observe happening in this picture? ! What can you infer?

Mold

Bacteria

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Inferences in Science !  It is important not to

confuse inferences with the observations on which they are based. !  Observation: hearing

the door bell ring !  Inference: some one

is at the door !  You are not observing

that someone is at the door!

Bias ! Experimenter’s bias – is leaning towards a result expected by the human experimenter. !  Also known as research bias ! Occurs when scientists unconsciously affect outcome of the experiment. !  in reading-‐up on the field !  in specifying and selecting the study sample !  in executing the experimental procedure !  in measuring exposures and outcomes !  in analyzing the data !  in interpreting the analysis !  in publishing the results.

Bias Neil deGrasse Tyson on Bias Some Descrip9ve Adjec9ves !  Depth: deep, full, shallow, empty, endless, infinite, steep !  Height: tall, short, small, vast, spacious, big, large, gigantic, tiny, huge, little, enormous, petite,

miniature, massive, mammoth, mighty, microscopic, medium, colossal !  Width: wide, thick, broad, narrow, thin, slender, skinny, slim, bulky, baggy, bulging !  Weight: heavy, light, strong, feathery, fat, stocky, stout, lean, skinny, slim, slender, crowded, trim,

lithe, plump, chunky !  Shape: circular, curved, crooked, curly, diamond-‐shaped, flat, jagged, oval, pointed, round,

rectangular, spiral, square, triangular, angular, arched, bell-‐shaped, bent, coiled, cone-‐shaped, conical, cylindrical, dome-‐shaped, egg-‐shaped, elliptical, erect, flat, flat, forked, geodesic, heart-‐shaped, hexagon-‐shaped, hollow, level, molded, oblong, obtuse, octagonal, pentagon-‐shaped, pyramidal, rambling, scalloped, straight, symmetrical, tunnel-‐shaped, upright, amoeba-‐like

!  Sounds: barking, crackling, crying, dripping, echoing, fluttering, giggling, hissing, howling, jingling, knocking, laughing, moaning, neighing, popping, quarreling, ringing, roaring, sizzling, swishing, tapping, thumping, whistling, yelling

!  Textures: blunt, brittle, coarse, crumbly, dense, flexible, fluffy, glossy, gritty, jagged, mushy, pebbly, prickly, tough, wrinkly, rocky, rough, scaly, shaggy, sharp, silky, slimy, smooth, soggy, spongy, springy, squishy, thorny, velvety

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Mystery Vial Lab -‐ answers !  1-‐ Marble !  2-‐ 6 Canadian dollars !  4-‐ Nails !  3-‐ A different grape lipstick !  6 – Steel cut oats (oatmeal) !  7 – 5 hair bands !  8-‐ banana boat sun tan oil !  9-‐ potting soil !  10-‐ Cherry Jello Powder !  11-‐ sesame seeds !  12 – garlic salt !  13 – vanilla extract !  14-‐ cinnamon !  15-‐ apple cider vinegar !  16 – tarragon vinegar !  17 – nail polish remover !  18-‐ pickle juice !  19 – loose peach tea !  20 – Very Green juice smoothie

!  21-‐ balsalmic vinegar !  22-‐ Cumin !  23-‐kosher salt !  24 – Cayenne extract !  25 – Coffee grounds !  26 – soy sauce !  27 – cherry juice !  28 – bread crumbs !  29-‐ mustard !  30-‐ baby oil !  32 -‐ bolts !  34 – nail polish remover !  36 – Neutrogena pink grapefruit face scrub !  37-‐ tea tree oil foot scrub !  44 – Curry powder !  45 – Caladryl lotion !  46 – Listerine mouth wash

Hypothesis-Based Science is a Search for Explanations !  Its one thing to observe and record, but what causes

the phenomenon is another

Methods of Hypothesis-based Science !  “Scientific Method”- ideal method, but not always a

structured step by step process. ! Science is actually less structured than most people

realize ! Despite this, there is one key element in HBS- the

hypothesis

Forming and Testing a Hypothesis ! Hypothesis - a suggested answer to a well-defined

scientific question !  Its an explanation on trial !  Allows you to make certain predictions that scientists

can test! !  No experimental evidence at this point. !  Must be specific and testable!

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Forming and Testing a Hypothesis !  People use hypothesis instinctively, its natural

!  Observation: the flash light doesn’t work !  Question: What’s wrong with it?

Hypothesis: The Batteries are dead.

Prediction: If the batteries are dead and you replace them with new ones, then the flashlight will work.

Test: Replace the batteries.

Forming and Testing a Hypothesis ! The inquiry continues with test of

alternative hypothesis. ! Next test?

!  Replace the bulb !  Test the switch !  Test the wire connections

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2 Outcomes of Scien9fic Inquiry !  1. Non-‐significant: The data show no effect, or such a small effect it could have happened due to chance. ! Hypothesis is NOT SUPPORTED/REJECTED !  Come up with a new hypothesis

2 Outcomes of Scien9fic Inquiry !  2. Statistically Significant: Data shows an effect that is likely not due to chance ! Hypothesis IS SUPPORTED

A Case Study in Hypothesis-‐Based Science ! Case study: an in-‐depth examination of something that really happened !  Law students train by analyzing actual documents of past cases

!  Case studies in science are posted in scientific journals and can boost your understanding of scientific method

From Observa9ons to Ques9on and Hypothesis !  It all begins with observations

!  Case study example: Mimicry (Flower-‐fly and honey bee) !  Many poisonous animals are brightly colored with distinctive markings

!  These serve as a warning to predators

!  There are also mimics or imposters. They looks like a poisonous species but are harmless

! Question: What is the function of such mimicry

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From Observa9ons to Ques9on and Hypothesis ! Hypothesis:

! Mimics benefit because the predators confuse them with the actual harmful species

Tes9ng a Predic9on of the Hypothesis !  In 2001 scientists designed a simple but clever way to test this hypothesis on look-‐alike snakes !  Eastern coral snake: venomous !  Scarlet king snake: harmless

Tes9ng a Predic9on of the Hypothesis ! The hypothesis predicts that predators will attack snake with bright red, yellow, and black rings less frequently than species lacking these warning markings.

! To test this, researchers made hundreds of artificial king snakes out of wire and plasticine. !  Two types of snakes made:

!  Snakes with black, yellow and red rings !  Plain brown snakes

Designing a Controlled Experiment ! Why did the experiment include artificial snakes that were plain brown? !  Contrast in color was needed to see if predators attack snakes based on their color.

!  If all snakes were the same, the number of attacks would indicate nothing about the effect of colored rings

!  If you want to test the effect of one condition, you need to provide a contrasting condition as well

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Tes9ng a Predic9on of the Hypothesis ! Researchers placed equal numbers of both types of artificial snakes throughout North and South Carolina

!  Four weeks later the snakes were retrieved ! They counted how many had been attacked by looking for bite or claw marks

! Most common predators: foxes, coyotes, raccoon, some black bears

Designing a Controlled Experiment ! A condition that can differ within an experiment is called a variable. !  In the artificial snakes, the variable is the presence versus the absence of the colored rings.

! Most often experiments test the effect of a difference of just one variable.

! An experiment that tests the effect of a single variable is called a controlled experiment.

Types of Variables Independent Variables

Dependent Variables

⚫ In an experiment it’s the condition that is manipulated or changed, BY THE SCIENTIST.

⚫ The variable that is observed and measured in an experiment. ⚫ They depend on the

independent variable.

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Designing a Controlled Experiment ! Controlled experiments try to eliminate or control other variables that could affect the outcome. !  Called Constants. ! Not simple !  Variables like weather or temperature could influence predator behavior in the snake experiment

!  In an ideal setting (a laboratory)-‐ climate and temperature can be controlled

!  This impossible in field experiments

Pasteur -‐ Spontaneous Genera9on Constants?

Elimina9ng Unwanted Variables ! How do we get rid of unwanted variables? ! Researchers divide the subjects (artificial snakes in this example) into 2 groups. !  Control group – NOT exposed to the EXTRA (Independent Variable) factor.

!  Experimental group – has the EXTRA (Independent Variable) factor

Elimina9ng Unwanted Variables ! The experiment was testing the effect of colored rings so the experimental group was the colored ringed snakes.

! The brown snakes served as a control group showing what happens in the absence of colored rings

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Elimina9ng Unwanted Variables ! Everything about the 2 snake groups was the same…the constants. !  Both made of the same material !  Both placed at random in the same locations !  Conditions such as light, temperature, and appetite of predators varies, but both groups were subject to the same variation

!  Thus color was the only consistent difference or variable between the groups

!  So any difference in attack rates between the groups could be attributed to color and no other variable

“If…,then…” Reasoning

!  Snake case study ! same reasoning as flashlight example.

Organizing and Interpre9ng Data ! Experiment is not over after data collected

! Often results don’t make sense until after much analysis of data

!  For quantitative data it helps to put it in a table or graph, this may reveal a pattern that you could not see in the raw data

Evidence ! Evidence consists of a collected body of data from observations and experiments.

!  Scientific evidence should be repeatable. ! Repeating observations and experiments of others should lead to similar evidence.

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Peer Review ! Experimental methods and results are evaluated by other scientists.

Science is limited !  Science is limited in the kinds of questions it can answer

! Only able to search for natural causes for natural phenomena

!  Supernatural explanations of natural events are outside of the bounds of science, there is no way to show they are false

Hypothesis !  Scientific hypotheses should lead to predictions that can be tested.

!  Some experiment must be able to reveal if hypothesis is false.

! Even hypothesis that stand up to repeated testing may be later revised or rejected

Language of science ! Turn to page 8 of your notes packet ! Use the list of prefixes and suffixes to define the words 1-‐20

! Use the list of prefixes to make up a new word ! Define your new word

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Theories ! A theory is a well tested explanation that made sense of a great variety of scientific observation. ! much broader in scope than hypothesis !  lead to major scientific advances ! Only accepted in science when supported by large body of experimental evidence.

!  Can be modified or discarded due to new evidence

Theories ! Germ theory

! mid 1800s illness was thought to be due to imbalances in the bodies “humours” or fluids

!  Research suggested it was due to microscopic organisms, such as bacteria.

! Once stated that disease causing microorganisms must be able to grow in a lab !  Prions and viruses do not fit this theory, so it has been changed as new evidence comes to light.

Louis Pasteur

Cell Theory & Germ Theory Draw the following table on the 3 x 5 card

Fill in the table as you view the videos.

Cell Theory What do they have in

common?

Germ Theory

Details: Details:

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Scien9fic Law !  Scientific law describes a statement or equations that reliably predicts patterns or events in nature. !  Ex: Law of conservation of energy – energy may change form but it cannot be created nor destroyed

!  It does not provide an explanation…theories do provide explanation.

Communica9on ! Communicating findings is important in science

!  Allows scientists to check each other’s claims by repeating each other’s investigations

!  Validation

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Technology ! Technology and science are related, but their goals and methods are different

! Goal of science: understand nature

! Goal of technology: to apply scientific understanding for some specific purpose

Imaging technology ! Microscopes provide new views of life

!  Light microscope –1500 x magnification, can view living or preserved specimens

!  Scanning electron microscope (SEM) – 100,000 x magnification, can only view preserved specimens in a vacuum !  Bounces electrons off the surface to make a 3D image

!  Transmission electron microscope (TEM) – 100,000 x magnification, can only view preserved specimens in a vacuum !  Transmits electrons through a specimen to make a 2D image

Medical Imaging ! X rays – X rays pass through soft tissue but are blocked by bone and teeth.

! MRIs – Magnetic Resonance Imaging – uses a strong magnetic field to produce a cross section image of part of the body. !  Good for soft tissue. !  fMRI (functional) can show activity in tissue.

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Models ! Models are physical, mental, or mathematical representations of how people understand a process or an idea ! Help explain and evaluate the natural world

Computer Models ! Complex systems are modeled on computers !  Epidemiology – how diseases spread

! How medicines might affect the body.

Bellwork 9/9 !  9. Why are models used in science? Give a specific example of when a model could be used.

!  10. How are the goals of science and technology different?

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Molecular gene9cs ! Gene – segment of DNA that stores genetic information

! Molecular genetics -‐ study and manipulation of DNA on a molecular level. !  Transgenic plants and animals !  GMO’s (genetically modified organisms) !  Gene replacement

! Genomics – study and comparison of genomes (entire DNA map) within and across a species.

Demonstrates the possibility of changing the genetic makeup of cells to prevent the body’s rejection of transplanted organs.

Biology and your Health !  Food related causes of illness.

!  Food poisoning ! Mad cow disease !  Food allergies

! Biology helps us assess these issues !  Sunscreen !  Exercise ! Drug and alcohol use

Biology and the World Around you ! Amphibian Deformities (1995, Minnesota)

!  Causes? !  Chemicals in the water !  UV radiation !  Infection (trematodes) !  Predation

! How could biology help you to better understand environmental issues?

Biotechnology

! Biotechnology – use and application of living things and biological processes. ! Microorganisms make bread and cheese

! DNA testing to free a criminal ! Transgenics -‐ transferring genes from one organism to another.

!  GMO’s !  Insulin making bacteria

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Unanswered ques9ons ! Benefits and Ethical Considerations !  Genetic screening

!  Structure of DNA was described in 1953, mapped by 2003. !  Can cancer be prevented or cured? ! How do viruses mutate? ! How are memories stored? !  Life on other planets?

!  Lots of unanswered questions still exist today!!

Unifying Themes of Biology !  1. All levels of life have systems of related parts

!  2. Structure and function are related in biology

!  3. Organisms must maintain homeostasis (internal balance) to survive in diverse environments

!  4. Evolution explains the unity and diversity of life.

Theme #1: All levels of life have systems of related parts !  System is an organized group of related parts that interact to form a whole. !  Smallest – molecules !  Largest – biosphere

! Ecosystem – physical environment with different species that interact with one another and with nonliving things.

Theme #2: Structure and Func9on are related in Biology ! Examples

!  Car parts have specific functions

!  Body parts have specific functions

! Molecules have specific functions

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Theme #3: Organisms must maintain homeostasis to survive diverse environments ! Homeostasis – the maintenance of constant internal conditions in an organisms !  Temperature !  Blood sugar !  Acidity

! Breakdowns in homeostasis are often life threatening.

Theme #4: Evolu9on explains the unity and diversity of life ! Adaptation – an inherited trait that gives an advantage to individual organisms and is passed on to future generations. !  Evolutionary adaptations are different than adapting by choice.

! Unity and Diversity – Evolution accounts for both of these ! Humans and bacteria – both have DNA and RNA, same sources of energy, similar cell structures.

Characteris9cs of Life ! All living things have the following in common

!  1. Cells – the basic unit of life !  2. Need for energy !  3. Response to environment – to survive !  4. Reproduction and development

!  Reproduce – pass on genetic material (DNA) to offspring !  Develop – mature to be able to reproduce

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Extra IV and DV Prac9ce ! On following slides….. !  Students watched a cartoon either alone or with

others and then rated how funny they found the cartoon to be.

!  Independent Variable:

! Dependent Variable:

! A comprehension test was given to students after they had studied textbook material either in silence or with the television turned on.



!  Some elementary school teachers were told that a child’s parents were college graduates, and other teachers were told that the child’s parents had not finished high school; they then rated the child’s academic potential.



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! Workers at a company were assigned to one of two conditions: One group completed a stress management training program; another group of workers did not participate in the training. The number of sick days taken by these workers was examined for the two subsequent months.



!  Students at a University were split into two groups and each received a different text for a philosophy course. Once group received a traditional text book, while the other received an interactive textbook on a tablet computer. After the course, the final exam marks between the two groups of students was compared.



Design an Experiment ! Eating breakfast in the morning increases the ability to learn in school.

!  IV: ! DV:

Design an Experiment ! Drinking energy drinks makes people more aggressive.

!  IV: ! DV:

Unit1-TheScienceofBiology MS B · 2019. 9. 10. · Test the wire connections . 9/9/19 9...

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