Things to Remember VCE Biology

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General SAC Tips

Biological Drawings

Full intact cell always to be drawn

Answering Questions

Get to the point of the question

Use dot points

When asked to Describe -> describe what is going on in the picture/diagram not why it is happenig

Use terminology

Do not give more than one answer/ do not contradict yourself

Draw diagrams

Reading Questions

Diagrams -> think from the examiner's point of view, figure out what it is conveying

Read question and highlight points

Answering using graphs

Quote numbers from the graph

Use technical language like plateau for a flat line

State general trends

Use annotations

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Experimental Design

Variables

Shown on graph axis if provided

Independent variable - what you are changing

Dependent variable - what you are measuring as a result of that change

Controlled variables - remain the same in all set applications

Control group - a comparison for the results/how/show the results are due to the change in the independent variable, multiple control groups are needed with or without independent variables if it cannot be removed showing different levels

Hypothesis

If/then relationship showing cause and effect

Independent and dependent variable

Method

Annotated diagram - explains through detailed instructions concerning quantities like time and amount, set up, observations, tables and collection of results

Repetition of experiment multiple times - reducing the change of error effecting the outcome

Results

Quantitative -> preferred as it is less objective and not biased

Qualitative -> subjective

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Movement of Molecules

Import and Export of Molecules into and Out of the Cell

Active transport - Ions like sodium and calcium are transported using active transport if concentrations are different

Interpreting Percentage Change Graphs

No % change equals the same concentration inside and outside the cell

The cell is isotonic

Identifying changes in Cells

State in terms of has become more flaccid and turgid and state the reason why this is thought to be so (boundary moved further away from cell wall)

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Enzymes

Important Details

Enzyme are not used up in the process of a chemical reaction

Enzymes catalyse reactions by destabilising bonds in the substrate so that it is more reactive

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Biochemical Processes

General

When asked to describe some energy conversions, refer to cellular respiration and photosynthesis

Endergonic or exergonic - refer to the breakdown or formation of chemical bonds

ATP to ADP - describe the cycle

Cellular Respiration

Many cells can carry out anaerobic and aerobic respiration at the same time

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Samples of Good Answers

Identify the type of chromosomal abnormality involved and the error in cell division which most likely gave rise to the abnormality.

Aneuploidy - one extra chromosome present in the cell, specifically trisomy

Non-disjunction - during nuclear division one pair of chromatids was not separated during anaphase

Explain why there is a difference in the way the bacteria have grown on plates A and C

Plate C - only some bacteria transformed

Discrete colonies - only transformed bacteria grow because resistant to copper

Plate A = all bacteria grown hence continuous growth due to no copper inhibition

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Mitosis and Meiosis

A replicated chromosome has two chromatids, double stranded chromosome but when they separate, they are no longer called chromatids but single stranded chromosomes.

Homologous chromosomes have the same gene loci - terminology

For familial Downs' Syndrome, the offspring that survive include two normal phenotypes, one with a translocated chromosome and one with no unusual chromasomes (normal) and one Downs' Syndrome phenotype with an extra chromosome 21

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Inheritance

A large difference in expected phenotypic ratio can be due to how the phenotype is affected by the environment

The dihybrid cross punnet square quick method = 9 dominant, dominant: 3 dominant, recessive: 3 recessive, dominant: 1 recessive, recessive

Pedigree Key show with and without disease for males and females -> therefore 4 keys

Usually shade in the disorder