UNIT 3 BIOLOGY - SUMMARY NOTES FOR THE VCAA EXAMS - Experimental Method, Plasma Membrane, and Membrane Transport

Sep 20, 2026

Unit 3 Biology summary notes for VCAA exams, written from a student study-scoring perspective, covering key concepts and experiment design. Content includes a glossary of biological macromolecule-related terms and endosymbiotic theory, plus an experimental-method checklist for variables, trials, hypothesis, outcomes, and expected trends. Additional sections define accuracy, precision, reliability/repeatability, validity, and error types (systematic, random, personal) and uncertainties. The notes also explain plasma membrane composition and fluidity, membrane transport processes, and how membrane permeability links to temperature and molecule diffusion.

LanguageEnglish

CategoryExam

FormatPDF

Pages67

Reading Time2 h 49 min

AccessFree to download

Unit 3 Biology - Summary Notes for the VCAA Exams

Glossary

Experimental Method

Plasma Membrane

Membrane Transport

Types of Membrane Transport

UNIT 3 BIOLOGY SUMMARY NOTES FOR THE VCAA EXAMS WRITTEN BY A STUDENT WHO OBTAINED A NEAR PERFECT STUDY SCORE UNIT 3 GLOSSARY Organic: Containing hydrogen and carbon Denatured: Permanent destruction of the characteristic properties of a biological macromolecule by disrupting its molecular conformation by heat, acidity, or other Endosymbiotic theory: ● Cells are engulfed by phagocytosis but not digested ● Cells live together is a mutually benefiting relationship, or symbiosis ○ Survival advantage ● Mitochondria and chloroplasts have intriguing similarities in structure, reproduction, biochemistry, and genetic makeup to certain prokaryotes. ○ Has its own singular circular DNA not bound within a nucleus ○ Has its own ribosomes ○ Double membrane bound ○ Reproduces by binary fission ○ Similar size Hydrolysis: The chemical breakdown of a compound due to a reaction with water. Opposite to condensation polymerisation Hydrophilic: Attracted to polar substances Hydrophobic: Attracted to nonpolar substances 􀂤 The School For Excellence 2020 Unit 3 Biology – A+ Student Generated Materials Page 1 EXPERIMENTAL METHOD ❏ What biological concepts are relevant to this experiment? ❏ What were the dependent, independent variables and controlled variables? ❏ What calculations have been performed? What values need to be measured in order to perform these calculations and how were they measured? ❏ How many trials were carried out? ❏ Based on the procedure, what outcome is expected? Hypothesis ● A statement that can be tested ● Cannot be proved → Must be supported or not supported by the data Independent variable ● What you change ● x-axis Dependent variable ● Must be measurable (how will it be measured?) ● y-axis Controlled variables ● Must state “ the same” ● To attribute the change in DV to change in IV Control group Repeat ● The experiment Large sample ● Eg. 100 mice Expected outcomes ● Reference IV and DV 􀂤 The School For Excellence 2020 Unit 3 Biology – A+ Student Generated Materials Page 2 Trend ● Suggests there is some kind of relationship between the independent and dependent variables ● Must be described fully and accurately ● Rapidly, smoothly, reached a peak, became constant, fluctuated Accuracy ● Obtaining the correct (true) measurement ● Not a quantity ● Increased by changing the way the experiment was conducted Precision ● Obtaining the same measurement over and over again ● Little spread about their mean ● Gives no indication of how close the results are to the true value ● Increased by having a larger sample size and averaging and removing outliers Reliability/Repeatability ● Obtaining same measurement if experiment is repeated again or by someone else ● Reliability of results can be evaluated by repeating the investigation and determining the degree to which the results vary. ● The purposes of reproducing experiments include checking of claimed precision and uncovering of any systematic errors from one or other experiments/groups that may affect accuracy. Experiments that use subjective human judgment or that involve small sample sizes or insufficient trials may also yield results that may not be repeatable and/or reproducible. ● Can be increase by repeating the experiment many times to reduce the effects of random errors in order to make the results more likely to be obtained if someone else repeats the experiment Validity ● Whether the results are due to change in IV affecting DV ● Increased by controlled variables 􀂤 The School For Excellence 2020 Unit 3 Biology – A+ Student Generated Materials Page 3 Systematic error ● Consistent error that occurs every time a measurement is taken ● Caused by the design of the experiment and the way it was conducted ● Cannot be eliminated by averaging ● Affects accuracy Random error ● Unpredictable variations in measurements over which you have little

FAQs

What makes a dependent variable suitable for an experiment?

The dependent variable must be measurable, with clear instructions on how it will be measured.

How do accuracy and precision differ in these notes?

Accuracy is obtaining the correct (true) measurement, while precision is getting the same measurement repeatedly with little spread around the mean.

What is the difference between systematic error and random error?

Systematic error is a consistent mistake caused by experimental design and cannot be eliminated by averaging. Random error involves unpredictable variations that affect precision and can be reduced with larger samples and averaging.

Sep 20, 2026

Uploaded by Chumphorn