Welcome to FLIS Biology 3A

Biology: fields of study Use the highlighter pen to match each type of scientist to the picture of what they study Botanist Ecologist Entomologist Herpetologist Ornithologist Palaeontologist Zoologist

Biology: fields of study Use the highlighter pen to match each type of scientist to the picture of what they study Botanist Ecologist Entomologist Herpetologist Ornithologist Palaeontologist Zoologist

What is biology? Biology is the study of living things and their interactions with each other and the non-living environment.

Biology is a science Science is a body of knowledge (what we have found out) Science is also the process by which we gain the knowledge (how we find out)

The Practice of Biology Introduces the skills you need as a scientist Provides the tools or processes you will use to study biology Is assessed across all modules in the course

What do scientists do Scientists collect data Scientists analyse and organise their findings Scientists share their findings

The scientific method Defining problems for investigation Making observations Asking questions and making inferences Investigating to find answers Forming hypotheses Making predictions Testing the hypotheses Making conclusions and sharing them

Observations and inferences

Observations – The cage is empty There are feathers on the ground There is a cat Inferences - The cat has eaten the bird There wasn’t any bird – the cat has been framed

Quantitative and qualitative observations Quantitative – using measurements Qualitative – descriptions eg colour, shape, roughness, shine, etc

Making observations Quantitative observations are Examples include Qualitative observations are Examples include Qualitative Quantitative

Making observations Quantitative observations are observations that can be measured Examples include length, width, mass, temperature, speed, humidity Qualitative observations are observations that can’t be measured Examples include colour, shape, texture, size (eg large or small) Qualitative Quantitative Brown Has fur Large Eats grass Has claws Height at shoulders Body length Body mass Body temperature Measurements of teeth, claws, etc Measurements of food volumes

Designing experiments When we design experiments we need to define how we intend to measure and collect results before we even start the experiment.

What’s going on here? Pose a question Suggest some answers Define your hypothesis Eg – the more detergent in the mix, the more bubbles we get The bigger the wire loop, the bigger the bubbles produced

What shall I change? Select one thing to test How will you change it? Define your independent variable Eg changing the amount of detergent, the size of the loop, the type of water used, etc

How do I know if it has an effect? What will I measure? How will I measure it? Define your dependent variable What will I compare it to? Define your control Eg size of bubbles – ruler Strength of bubbles – time they last Number of bubbles Experimental and control groups eg low detergent against high detergent, Hard water against rain water Big loop against small loop

How do I know my results are true? What do I need to keep the same? Define your controlled variables How can I make the experiment fairer? Define how you will increase reliability Eg Repeat the experiment Get others to replicate

Ways to increase reliability Use accurate measurements Repeat the experiment Increase the sample size Get someone else to replicate the experiment Share the results and get a review

The language of experimental design Hypothesis – statement to be tested by experiment – links independent and dependent variable eg bigger loops make bigger bubbles Independent variable – the thing you change eg the size of loop Dependent variable – the thing you measure eg the size of bubble The control – what you compare the experimental group to Controlled variables – the things that are kept the same in both experimental and control groups Reliability – measures to increase the fairness of the experiment

Problems with measurement Using them properly Using the right instrument

Accuracy in measurement Calibrate your equipment Use the right equipment for the job Use the equipment properly

Why is precision important? Look at the examples below. How would you measure their size?

Why is precision important? Look at the examples below. How would you measure their size? When designing experiments, you often need to define how the measurements need to be taken, as well as the instruments that are to be used.