Bridge to university · Sciences
Bridge: biology foundations for first year
Cell structure, membranes, macromolecules, genetics vocabulary, cell division and the scientific method, reviewed before first-year biology.
About this deck
Introductory biology at university covers a lot of ground quickly, and the lectures assume you already have the vocabulary. This deck reviews that core language. It covers cell theory and the difference between prokaryotic and eukaryotic cells, the main organelles, movement across membranes, the four classes of biological macromolecules and enzymes, genetics terms such as allele, genotype and dominant, mitosis and meiosis, photosynthesis and respiration in summary form, and the logic of experiments and variables.
It is intended for students entering life science, health science, nursing, kinesiology or environmental programs, and for anyone who took Grade 12 biology a while ago. Since biology rewards precise wording, try to say each definition aloud in your own words before flipping, then compare. Pair related cards, such as mitosis and meiosis or genotype and phenotype, and quiz yourself on the differences. Students often mix up diffusion and osmosis, think dominant means more common, confuse genes with alleles, and describe a correlation as if it proved a cause. If a definition feels vague, draw a quick sketch: a labelled cell or a Punnett square often fixes the idea better than rereading.
Before you start: Grade 11 biology; basic chemistry vocabulary (atom, molecule, bond) is helpful.
All 41 cards
Cover the definitions with a sheet of paper and test yourself, or use the study modes above.
Cells
- Cell theory
- All living things are made of cells, the cell is the basic unit of life, and new cells arise only from existing ones.
- Prokaryote
- A cell with no nucleus and no membrane-bound organelles, such as bacteria and archaea.Example: E. coli
- Eukaryote
- A cell with a nucleus and membrane-bound organelles, found in plants, animals, fungi and protists.Example: A human liver cell
- Plasma membrane
- A phospholipid bilayer with embedded proteins that controls what enters and leaves the cell.
- Nucleus
- Organelle wrapped in a double membrane that holds the DNA and controls which genes are expressed.
- Mitochondrion
- Organelle where cellular respiration produces most of the ATP a eukaryotic cell uses.
- Chloroplast
- Organelle in plants and algae where light energy is captured to make sugar.
- Ribosome
- A structure of RNA and protein that assembles amino acids into polypeptides, free in the cytoplasm or on rough ER.
- Endoplasmic reticulum and Golgi apparatus
- A membrane network that makes proteins and lipids, and a stack of sacs that modifies, sorts and ships them.
- Diffusion
- Net movement of particles from higher to lower concentration, with no energy input from the cell.Example: Oxygen entering a cell
- Osmosis
- Movement of water across a selectively permeable membrane toward the side with more dissolved solute.Example: A red blood cell swells in pure water
- Active transport
- Moving a substance against its concentration gradient using energy, usually from ATP, and a carrier protein.Example: The sodium-potassium pump
Macromolecules
- Carbohydrates
- Sugars and their polymers, such as starch, glycogen and cellulose, built from units like glucose; used for energy and structure.
- Lipids
- Water-repelling molecules including fats, phospholipids and steroids; they store energy and form membranes.
- Proteins
- Chains of amino acids folded into specific shapes that work as enzymes, transporters, signals and structural parts.
- Nucleic acids
- DNA and RNA: polymers of nucleotides that store and transmit genetic information.
- Enzyme
- A biological catalyst, usually a protein, that speeds a reaction by lowering its activation energy and is not used up.Example: Amylase breaks down starch
- Denaturation
- Loss of a protein's shape, and therefore its function, caused by heat, pH change or certain chemicals.Example: Cooking an egg white
- Dehydration synthesis and hydrolysis
- Joining monomers by removing a water molecule, and splitting polymers by adding one.
Genetics
- Gene
- A segment of DNA that carries instructions for a functional product, usually a protein.
- Allele
- One version of a gene. Humans carry two for most genes, one inherited from each parent.Example: B for brown and b for blue
- Genotype versus phenotype
- The genetic makeup, such as Bb, versus the observable trait, such as brown eyes.
- Homozygous and heterozygous
- Carrying two identical versions of a gene (BB or bb), versus two different versions (Bb).
- Dominant and recessive
- A trait that appears when one copy is present, versus one that appears only with two copies. It says nothing about how common a trait is.
- Monohybrid cross Bb x Bb
- The Punnett square gives BB, Bb, Bb and bb: genotype ratio 1:2:1 and, with B dominant, phenotype ratio 3:1.
- DNA replication
- Copying the genome before division; each new double helix keeps one original strand, so it is semi-conservative.
- Transcription and translation
- DNA is copied into mRNA in the nucleus, then mRNA is read at the ribosome to build a protein.
- Mutation
- A change in a DNA sequence; it may be harmful, neutral or occasionally helpful.Example: A single base swap
Cell division
- Mitosis
- Division of a nucleus that gives two genetically identical daughter cells; used for growth and repair.
- Meiosis
- Two rounds of division producing four genetically different cells with half the chromosome number; it makes gametes.
- Diploid and haploid
- Two sets of chromosomes (2n, 46 in human body cells) versus one set (n, 23 in human eggs and sperm).
Energy
- Photosynthesis summary
- 6CO2 + 6H2O + light energy -> C6H12O6 + 6O2, taking place in chloroplasts.
- Cellular respiration summary
- C6H12O6 + 6O2 -> 6CO2 + 6H2O, releasing energy stored as ATP, mostly in mitochondria.
- ATP
- Adenosine triphosphate, the short-term energy carrier that powers most work inside cells.
Scientific method
- Hypothesis
- A testable and falsifiable prediction about how variables are related, often written as an if...then statement.Example: If light intensity rises, then the rate of oxygen release will rise
- Independent variable
- The factor the experimenter changes on purpose.Example: Fertilizer amount
- Dependent variable
- The factor that is measured to see the effect of the change.Example: Plant height after four weeks
- Controlled variables
- Factors kept the same across all groups so they cannot explain the result.Example: Same soil, light and water for every plant
- Control group
- The group that does not receive the treatment and serves as a baseline for comparison.Example: Plants given no fertilizer
- Correlation versus causation
- Two variables moving together does not show that one causes the other; a controlled experiment is needed to test cause.Example: Ice cream sales and sunburns both rise in summer
- Peer review
- Evaluation of a study by independent experts before publication, aimed at catching errors and weak reasoning.