Chapter 1The Science of Biology

1.1 What is science1.2 Science in context

1.3 Studying life

Why do we take notes? • Restructuring information makes you think about it!• Make it easier to later pick out key bits of information

What is not taking notes?• Copying exactly what is in the textbook• Just writing out keyword definitions

Taking notes

Method 1 - Outline method•Start with theme•Use bullet points to gradually go into more detail on that theme• Science

• Gather and analyze evidence in organized way about natural world• Observing, thinking and knowing• Process not a thing• Look for patterns and connections• Based on fact• Form testable evidence based explanations

• Body of knowledge

• All objects in the universe are interactions between objects are governed by same natural laws

• Goal of Science• Explain the world through observable events and processes• provide natural explanations for events• predict future natural events

Method 2 - Cornell method

•Divide sheet into 3 areas•Bulk of text

summarized in blue•Green area – key

points•Yellow – summary of

key points of the text

Note taking areaCue

Summary

Cornell method - exampleScience – gathering and analyzing evidence in an organized way. It is a process – a way of observing and thinking. It can also refer to the body of scientific knowledge accumulated in the past. What makes science different? Only related to natural world, never supernatural phenomena. Scientists look for patterns and connections in organized and well structured data. All explanations are based on evidence and are testable

The universe is a system – everything in it interacts. Everything in the universe is governed by the same laws. Aim of science – explain the world around us by observing events and processes. Ultimate aim is to provide explanations for events in the natural world, and, through patterns, make predictions about the future.

Science is a process

Only natural world

Evidence based explanations

Same laws apply throughout universe

Science provides understanding

Make predictions

Science – process of looking for patterns and connections in data to form testable explanations of natural world processes. Goal is to provide explanations and make predictions about natural events

Hybrid of 2 methodsScience is a process

Only natural world

Evidence based explanations

Same laws apply throughout universe

Science provides understanding

Make predictions

Science – process of looking for patterns and connections in data to form testable explanations of natural world processes. Goal is to provide explanations and make predictions about natural events

• Science • Gather and analyze evidence in organized way about

natural world• Observing, thinking and knowing• Process not a thing• Look for patterns and connections• Based on fact• Form testable evidence based explanations

• Body of knowledge

• All objects in the universe are interactions between objects are governed by same natural laws

• Goal of Science• Explain the world through observable events and

processes• provide natural explanations for events• predict future natural events

Method 3 - Charting/mapping methodScience

Natural World

Observing Thinking

Organized data

Patterns Connections

Evidence based testable explanation

Body of knowledge

Goals

Governed by universal laws

Explain the world through observable events and processes

Make predictions about future

Provide natural explanations for events

Extra points•These are only guides

• Other methods out there – flow charts, descriptions• Find what works for you

•Use coloured pens, underlining, Bold, CAPITAL LETTERS, effectively

•Use abbreviations • Common ones are • =, /, • No Need for complete sentences

Chapter 1: What is Science? • Gathering and analyzing evidence about the natural world

• Organized and methodical• Science is a process

• Evidence based explanations• Make observations • Identify patterns• Explain processes in the natural world

• Dates back to Ancient Greece – the first to realise that all things are governed by universal natural laws

• It is constantly evolving• All research builds upon previous studies• Often more questions are raised than are answered• To actual prove something is very rare

What is research? How is it performed?

•Research starts with an idea• Built upon previous research, and/or observations, and a bit of imagination

• Leads to an inference• A logical interpretation based upon what is already known

•This leads to hypothesis• A testable scientific explanation

• Often based on a limited set of observations• Can be supported or rejected• Starting point for further investigation

•Then you start experimenting…

How do you go about designing an experiment? •Variable: any factor, trait, or condition that can exist in differing

amounts or types• Examples – temperature, light, time

• Ideally one variable should be changed at a time in an experiment• All others should be kept constant

• Otherwise how do you know what is responsible for any observations

• Fundamentals for a controlled experiment

•Variable that is deliberately changed – Independent Variable

•Variable that is observed/measured – Dependent variable

How do we know it wouldn’t have happened anyway? •Control Group

•Exposed to the same conditions as the experimental group, except for the one independent variable

• If measuring effect of fertiliser concentration on plant growth, one group would have no fertiliser at all

•Multiple repeats increase confidence in result• Make sure it wasn’t a fluke!

What different types of data can be collected? •Quantitative

• Data that can be directly measured• Height, weight, amount of water etc…

•Qualitative• Descriptive data, Characteristics that can’t be counted directly• Provides additional information for a sample

• Smell, taste appearance etc….

• Data is collated and organised to look for trends and patterns.

• Sources of error• Can be caused by the tool used, the user, or variation in the sample set• Mitigated through large sample set and multiple repeats

Conclusions

•Experimental data used to support, refute or revise the hypothesis

•Often not possible to fully support or refute a hypothesis, but work forms the basis for future investigations

•This cycle is often repeated many times

• Sometimes experiments aren’t possible • Animal research done through observations• Medical research conducted on people already exposed to a dangerous

chemical

How are results effectively communicated to the world? • Science is often built upon previous work published in Peer reviewed

scientific journals • Journal article is basically a very detailed lab report

•Peer review means that it has been read and commented on in detail by 2 or more academics in the same field of study• Doesn’t mean work is correct…..

• Scientists get together, discuss results, formulate new ideas

What is the difference between a scientific theory and a scientific law? •A theory in science is different to how we use it in everyday life

• Built upon many scientific studies• A theory applies to a well tested explanation unifying a variety of different

ideas/hypothesis

•Theories can become dominant, but are not considered absoloutley true

• Scientific laws – Always valid under the same conditions• Should imply a causal relationship between elements

• F= ma is a great example!

Science overview flowchart

IdeaBackground

reading/Observation

Publish Work

Hypothesis ConclusionsExperiment

Scientific Theory

Scientific Law If you are doing

groundbreaking scienceIf you are

amazing!

What is a Bias?

•Particular preference or point of view• Very personal• Should be avoided

• Science aims to be objective• Not always possible• Mitigated through collaboration

Where do ideas come from?

•Good scientists• Curious• Skeptical• Open minded• Creative

•Existing practical problems

•Technology• Advancements in technology further scientific innovation

• Communication• Peer reviewed work – sharing ideas, test and evaluate each others work

Science in Context

•How does science influence society?• Scientific research is strongly influenced by societal need• Provides answers to questions that affect our day to day life

•How does society influence science? • Ethics• Morality

•Who should pay for science?• In a product safety student, who should pay for research? Companies to

maintain high standards or the government to protect the people?

Why is it important to understand how science is performed and ideas are developed?

•Provide a critical viewpoint

•Helps to assess the validity of ideas

Why is it important to know the limitations of Science? • Important to know what questions science can’t answer

What makes something alive?

•Made up of basic units called cells• Smallest unit considered fully alive• Cells can grow, respond to stimuli, and reproduce • Cells are complex and highly organised

Are based on a universal genetic code

•All molecules store information needed to live, grow and reproduce in genetic code• Written into DNA• Essentially copied and pasted from parent to offspring • Almost identical for every organism on Earth

Obtain and used materials and energy

•All organisms grow, develop and reproduce• This requires energy

•Energy obtained via metabolism• Combination of chemical reactions through which an organism builds up or

breaks down materials

Grow and develop

•All organisms have patterns of growth and development

•During development a fertilised egg continues to divide

•As they divide, they differentiate • Look different from each other• Perform different functions

Reproduce

•They must be able to produce new similar organims

• Sexual reproduction• Two parents cells combine to produce first cell of new organism

•Asexual reproduction• Single offspring produces identical cell

Respond to stimuli

• Stimulus - signal to which an organism will respond

•Organisms detect and react to stimuli from their environment• Move towards food if hungry• Move away from danger for protection

Change over time

•Groups of things will physically change or evolve over time

•Evolutionary theory suggests that life can be linked to a common origin very early in Earth’s history

•Evidence found in shared DNA between organisms

• Fossils• Shared physical features and structures

Maintain stable environments

•Need to maintain stable environment despite changes in external conditions• Which can sometimes be dramatic

•This process is called homeostasis

Key ideas• Cells – cellular basis of life

• Unicellular and multicellular organisms• Many different types of cells

• Heredity • Information coded by DNA – same for 3.5 billion years• DNA makes you and all living things unique

• Energy and Matter• Autotrophs – make their own energy from light or chemicals• Heterotrophs – ingest food

• Growth, development and reproduction• New organisms always smaller than parents

• Homeostasis• Small variations to internal environment can often result in serious consequences

Key themes continued• Evolution

• As a group living things evolve.• Genetic and physical evidence

• Structure and Function• Major groups of organisms have evolved a collection of structures that make functions possible as new

environments are encountered

• Diversity of life• Large variety of life on earth• Major similarities at molecular level• Explained through evolutionary theory

• Interdependence • Everything connected on Biosphere (living planet)

• Dependent on cycling of matter and flow of energy

• Science as a way of knowing• Science is not just facts! • Allows people to marvel at world around• Live successfully in the biosphere!

Biology is an exciting diverse subject… • There are many overlapping fields that use different tools to study life from molecular level to the entire

planet!

• Numerous different fields..• Ecology

• Interactions amongst organisms and the environment• Environmental Science

• Applied part of ecology – conservation, management etc…• Biotechnology

• Use of living systems and organisms to develop or make products – e.g. microorganisms in antiobiotic production

• Genomics• Applies DNA sequencing methods and recombinant DNA to analyze the function and structure of

genomes• Molecular biology

• Structure and function of macromolecules essential for life – proteins, nucleic acids• Zoology

• Structure, embryology, evolution, classification habits and distributions of all animals

Which can lead to a number of exciting different careers

A Key unifying concept is safety…

•All science experiments have to be conducted in a safe and professional manner

• Follow all instructions carefully

•Ensure you fully understand procedures and all safety precautions• Read lab skills appendix B A-11 to A13

•Before starting any lab work ensure that you understand the entire procedure

Metric system

•1km – convert to metres

•0.45 liter – convert to milliliters

•5000 milligrams – convert to grams

•130 metres – convert to kilometers

•2500 mililetres – convert to liters

•0.017 grams - convert miligrams

Summary

•Design an experiment to study how temperature affects the rate at which sliced apples turn brown• Hypothesis• Variables• Experimental groups

Key points summarized

• Independent variable

•Dependent variable

•Control

•Hypothesis

Key summary continued

•Bias

•Ethical/moral implications of science

•What makes something alive?

•Unifying concepts in Science