Year 12 Biology study notes and practice questions

For Year 11 and 12 students sitting the HSC, VCE, QCE, SACE, WACE and more. Each unit has short study notes, flashcards and practice questions, and the app builds timed practice exams from the whole course.

• DNA and protein synthesisDNA structure and replication; Transcription and RNA processing; The genetic code and translation; Gene expression and regulation
• Meiosis and inheritanceMeiosis and variation; Monohybrid inheritance; Multiple alleles and sex linkage; Dihybrid crosses and pedigrees
• Genetic change and biotechnologyMutations; Causes and consequences; Biotechnology tools; Applications and ethics
• Infectious diseasePathogens; Transmission and control; Immune response; Vaccines and epidemiology
• Homeostasis and non-infectious diseaseHomeostasis and feedback; Regulating temperature, glucose and water; Causes of non-infectious disease; Epidemiology and technologies

4 multiple choice and 2 written questions. Try each one before you open the answer. Written answers show the model answer and what a full-marks response needs.

1. Question 1. DNA and protein synthesisMultiple choice

   If 30% of bases in DNA are guanine, adenine makes up…

   1. A40%
   2. B20%
   3. C30%
   4. D70%
   Show answer

   B. 20%

2. Question 2. Meiosis and inheritanceMultiple choice

   A colour-blind man and a homozygous normal woman: chance of a colour-blind son?

   1. A50%
   2. B0%
   3. C25%
   4. D100%
   Show answer

   B. 0%

   Sons get their X from the mother.

3. Question 3. Meiosis and inheritance: multiple alleles and sex linkage3 marks

   A woman with blood group A and a man with blood group B have a child with blood group O. Use genotypes to explain how this is possible, and give the probability of their next child having group AB.

   Show model answer and marking criteria

   Model answer. A child with blood group O must be ii, so each parent must have passed on an i allele. The mother is therefore Iᴬi and the father Iᴮi. Their cross gives IᴬIᴮ (AB), Iᴬi (A), Iᴮi (B) and ii (O), so the probability that the next child is group AB is 1 in 4, or 25%.

   A full-marks answer:

   • Child O is ii, so each parent must carry i: mother Iᴬi, father Iᴮi
   • Punnett square: IᴬIᴮ, Iᴬi, Iᴮi, ii
   • Probability of AB = 1/4 = 25%
4. Question 4. Genetic change and biotechnologyMultiple choice

   UAU (Tyr) changes to UAC (Tyr). This is a…

   1. ASilent mutation
   2. BMissense mutation
   3. CNonsense mutation
   4. DFrameshift
   Show answer

   A. Silent mutation

5. Question 5. Genetic change and biotechnology: biotechnology tools3 marks

   Explain how gel electrophoresis separates DNA fragments.

   Show model answer and marking criteria

   Model answer. DNA fragments are loaded into wells at one end of an agarose gel in a buffer, and an electric current is applied. Because of its negatively charged phosphate groups, DNA moves towards the positive electrode. The gel acts like a sieve, so smaller fragments move faster and further than larger ones. Fragment sizes are estimated by comparison with a DNA ladder of known sizes.

   A full-marks answer:

   • DNA samples are loaded into wells in an agarose gel and an electric current is applied
   • DNA is negatively charged (phosphate groups), so it moves towards the positive electrode
   • Smaller fragments move more easily through the gel and travel further; sizes are found by comparison with a ladder
6. Question 6. Infectious diseaseMultiple choice

   Tuberculosis is caused by a…

   1. AVirus
   2. BBacterium
   3. CPrion
   4. DFungus
   Show answer

   B. Bacterium

A few of the 91 Year 12 Biology flashcards. In the app they use spaced repetition: rate each card Again, Hard, Good or Easy and it comes back just before you would forget it.

• NucleotidePhosphate + deoxyribose (or ribose) + nitrogenous base.
• Homologous chromosomesA matching pair, one from each parent, with the same genes.
• SubstitutionOne base replaced by another.
• PathogenA disease-causing agent.

Biology questions turn on precise terms and the verb in the question: describe, explain, assess and evaluate each ask for something different. Learn processes as ordered steps, link structure to function, and practise data questions: read the axes, quote values with units and explain the trend.

Press Study for me and the app builds a 15 to 20 minute session from the cards that are due, the mistakes that are due and questions on your weakest topics. Practice questions come in three levels, and anything you get wrong comes back 1, 3 and 7 days later until you get it right. When an exam is close, sit a timed practice exam with AI marking.

Your state, your exam

Biology goes by different names around Australia. In the app the course shows under your state’s name: NSW, VIC, QLD, SA, WA, TAS, ACT, NT: Biology.

When you set up Year 12, you pick your state (NSW, VIC, QLD, SA, WA, TAS, ACT or NT) and your subjects. The AI then pitches explanations and marking at your certificate’s level. Courses differ between states, so compare the units above with your course outline, and turn your class notes into extra decks for anything that’s different.

Biology in Year 11

Year 11 Biology study notes and practice questions.

More Year 12 courses

Year 12 Maths Advanced, Year 12 Maths Standard, Year 12 English, Year 12 Modern History, Year 12 Chemistry, Year 12 Business Studies, Year 12 Legal Studies, Year 12 PDHPE. All Year 11–12 subjects.