VCE Biology Unit 3&4

Biology unit 3 and 4

Procedure

The set of processes used to define the scientific method typically including a hypothesis, experiment, observation, analysis, conclusion, and evaluation.

Hypothesis

If the (DV) then the (IV).

Independent variable

Variable that is manipulated and has a direct effect on the DV.

Dependent variable

The measured variable that is observed/recorded.

Repeatability

The ability of the experiment to be repeated identically in the same environment.

Precision

The degree to which the results are consistent.

Accuracy

The degree to which the results are close to the true value.

Reproducibility

The ability of the experiment to be repeated with the same materials and method in a different environment.

Validity

The experiment is measuring what it's supposed to be measuring.

Bar Graphs

Different groups of data.

Line graphs

Ranged set or continuous data.

Control set up

The experiment without the independent variable.

Controlled variables

Variables that are used to keep the experiment and control set up the same except for the independent variable.

Experiment

A step in the scientific method where a hypothesis is tested.

Observation

The act of gathering data or information through the senses.

Analysis

The process of examining data or information to uncover patterns, relationships, and insights.

Conclusion

A statement that summarizes the findings of an experiment and determines whether the original hypothesis was supported or refuted.

Method

The specific procedure or technique used to conduct an experiment.

Investigation

The process of exploring a scientific question or problem through systematic research and experimentation.

Experimental Set-up

The arrangement and conditions of an experiment that includes the independent variable.

Control Set-up

A set-up used to compare and confirm findings in the experimental set-up, which does not have the independent variable.

Controlled Variable

Factors that are applied in both setups to ensure that only one variable is tested at a time in an investigation, making it valid.

Results

The data or findings obtained from an experiment, usually presented in graphs or tables.

TAILS

A mnemonic device used to remember the components of a graph, including title, axis, interval, label, and scale.

Random Errors

Unpredictable events or mistakes that affect the results of an experiment, such as outliers or human errors.

Systematic Errors

Errors that occur in the measuring system and affect every single measurement, often requiring recalibration of machines.

Enzymes

Proteins that act as catalysts in biochemical reactions, speeding up the rate of chemical reactions by lowering the activation energy.

Catalyst

A substance that increases the rate of a chemical reaction without being consumed in the process.

Enzyme Functions

The specific roles or tasks performed by enzymes in biochemical reactions.

Substrates

The substances that bind to the active site of an enzyme and undergo a chemical reaction.

Coenzymes

Non-protein organic molecules that assist enzymes in their catalytic functions.

Active Site

The region on the enzyme where specific substrates bind and undergo a chemical reaction.

Anabolic

A type of reaction that builds up larger molecules from smaller ones, requiring energy (endergonic).

Catabolic

A type of reaction that breaks down larger molecules into smaller ones, releasing energy (exergonic).

Endergonic

Reactions that require an input of energy to proceed, often referred to as uphill reactions.

Exergonic

Reactions that release energy as they proceed, often referred to as downhill reactions.

Activation Energy

The energy required to initiate a chemical reaction, which enzymes lower to increase the rate of reaction.

Denature

The change in the active site of an enzyme, rendering it useless and unable to catalyze reactions.

Optimum Temperature

The temperature at which an enzyme functions most efficiently.

Saturation Point

The point at which all active sites of an enzyme are occupied by substrates, resulting in a stable reaction rate.

Substrate Concentration

The amount of substrate present in a reaction, which affects the rate of reaction until the point of saturation is reached.

Cofactors

Inorganic ions or metal ions that assist enzymes in their catalytic functions.

Feedback Inhibition

A regulatory mechanism in which the end product of a metabolic pathway inhibits the activity of an enzyme in the pathway.

Metabolic Pathway

A series of interconnected enzymatic reactions that lead to the synthesis or breakdown of molecules in cells.

Dephosphorylation

The removal of a phosphate group from a molecule.

Phosphorylation

The addition of a phosphate group to a molecule.

ATP

Adenosine triphosphate, a high-energy molecule used as a source of energy in cellular processes.

ADP

Adenosine diphosphate, a lower-energy molecule that results from the hydrolysis of ATP.

Mechanic Work

The work performed by enzymes in moving or rearranging structures within cells.

Nucleotide

A building block of nucleic acids, consisting of a sugar, a phosphate group, and a nitrogenous base.

Hydrolysis

The chemical breakdown of a compound due to a reaction with water.

Hydrolyse

The process of breaking down a compound through hydrolysis.

Loaded

Referring to ATP, it means that the molecule is fully energized and ready to release energy.

Unloaded

Referring to ADP, it means that the molecule is not fully energized and requires energy input to become ATP.

Inorganic Phosphate (Pi)

A phosphate ion that is not part of an organic molecule.

Organic

Referring to a molecule that contains carbon atoms.

Inorganic

Referring to a molecule that does not contain carbon atoms.

Cellular Respiration

The process in which cells produce energy by breaking down glucose and other molecules.

Enzymes

Proteins that speed up chemical reactions in cells, including those involved in cellular respiration.

Adenine Triphosphate (ATP)

A molecule that stores and releases energy for cellular processes.

Hydrolysis

The process of breaking down ATP into ADP and phosphate by adding water.

ATPase

An enzyme that catalyzes the breakdown of ATP into ADP and phosphate.

Exergonic Reaction

A chemical reaction that releases energy.

ATP Synthesis

The process of creating ATP from ADP and phosphate using ATP synthase.

Coenzymes

Molecules that assist enzymes in their catalytic functions.

NAD+ and FAD

Coenzymes that accept and transport electrons during cellular respiration.

Glycolysis

The first step of cellular respiration, in which glucose is broken down into pyruvate.

Krebs Cycle

The second step of cellular respiration, in which pyruvate is further broken down to release energy.

Electron Transport Chain

The final step of cellular respiration, in which electrons are transported and used to generate ATP.

Anaerobic Respiration

The process of producing energy without oxygen, typically through fermentation.

Fermentation

A metabolic process that converts pyruvate into either lactic acid or ethanol.

Oxygen Concentration

The amount of oxygen present, which affects the rate of cellular respiration.

Glucose Concentration

The amount of glucose available, which affects the rate of cellular respiration.

Biofuels

Renewable fuels made from recently living organisms, such as plants and algae.

Photosynthesis

The process by which plants convert sunlight into energy in the form of glucose.

Light Dependent

The stage of photosynthesis that requires light and produces ATP and NADPH.

Light Independent (Calvin Cycle)

The stage of photosynthesis that does not require light and produces glucose.

Autotrophs

Organisms that can produce their own food through photosynthesis.

Heterotrophs

Organisms that rely on consuming other organisms for food.

Stomata

Small openings on the surface of leaves that allow for the exchange of gases.

Xylem

Tubes in plants that transport water from the roots to the leaves.

Phloem

Tubes in plants that transport food (sugar) from the leaves to other parts of the plant.

Photosynthesis

The process by which plants convert sunlight, water, and carbon dioxide into glucose and oxygen.

Chloroplast

The organelle in plant cells where photosynthesis takes place.

Reduction

The gain of electrons in a chemical reaction.

Oxidation

The loss of electrons in a chemical reaction.

NADP

A molecule that picks up hydrogen ions released during photosynthesis and becomes NADPH.

ATP

Adenosine triphosphate, a molecule that stores and releases energy for cellular processes.

Xylem

Tubes in plants that carry water from the roots to the leaves.

Phloem

Tubes in plants that carry food to all parts of the plant for cellular respiration.

Thylakoid

Discs in the chloroplast filled with chlorophyll where the light-dependent stage of photosynthesis occurs.

Stroma

The fluid-filled space in the chloroplast where the Calvin cycle, or light-independent stage of photosynthesis, occurs.

Calvin cycle

The process in the stroma where carbon dioxide, ATP, and NADPH are used to synthesize glucose.

Rubisco

An enzyme required for the fixation of carbon dioxide in the Calvin cycle.

C3 plants

First product is PGA (3c), undergoes photorespiration, Co2 fixing enzyme is Rubisco, 1 CO2 Fixation

C4 plants

Plants that use an additional step before the Calvin cycle to fix carbon dioxide, making them more efficient in hot and dry conditions.

CAM plants

Plants that open their stomata at night to trap carbon dioxide and store it for use during the day, making them adapted to hot and dry conditions.

Stomata

Openings on the surface of leaves that allow for gas exchange.

Photorespiration

A process that occurs when there is a lack of carbon dioxide entering the plant, resulting in oxygen binding to Rubisco instead and producing carbon dioxide.

Proteins

Biomacromolecules made up of amino acids that have various functions in cells and organisms.