CAPE Biology Unit 1 flashcards
CAPE Biology Unit 1 · Build recall with a focused review session.
32 cards. Read the term and the definition here. The deck at the top of this page is optional.
- Prokaryotic cell
- A cell lacking a membrane-bound nucleus and organelles, with circular DNA in a nucleoid, 70S ribosomes, and often a peptidoglycan cell wall.
- Eukaryotic cell
- A cell containing a true nucleus and membrane-bound organelles such as mitochondria, endoplasmic reticulum, and Golgi apparatus.
- Mitochondrion function
- Site of aerobic respiration where ATP is produced; has a double membrane with folded cristae and an inner matrix containing enzymes and circular DNA.
- Rough endoplasmic reticulum
- A membrane system studded with ribosomes that synthesises and transports proteins, which are then modified and packaged by the Golgi apparatus.
- Endosymbiotic theory
- The idea that mitochondria and chloroplasts originated from engulfed prokaryotes, supported by their double membranes, circular DNA, and 70S ribosomes.
- Magnification formula
- Magnification equals image size divided by actual size; units must be converted so both measurements use the same scale.
- Resolution
- The ability of a microscope to distinguish two points as separate; electron microscopes resolve better than light microscopes because electrons have a shorter wavelength.
- Osmosis
- The net movement of water across a selectively permeable membrane from a region of higher water potential to a region of lower water potential.
- Water potential
- The tendency of water to move into a system; pure water at atmospheric pressure has a water potential of zero kPa, and solutes lower it.
- Active transport
- Movement of substances against a concentration gradient through carrier proteins using ATP; it is saturable and stopped by metabolic inhibitors.
- Fluid mosaic model
- A description of membrane structure as a phospholipid bilayer with proteins, cholesterol, and glycoproteins able to move within it.
- Glycosidic bond
- A covalent bond formed between two monosaccharides by a condensation reaction, releasing water; it joins sugars into disaccharides and polysaccharides.
- Peptide bond
- A covalent bond joining the carboxyl group of one amino acid to the amino group of another, formed by condensation with the release of water.
- Primary protein structure
- The sequence of amino acids in a polypeptide chain, determined by the gene and held together by peptide bonds.
- Tertiary protein structure
- The three-dimensional folding of a polypeptide stabilised by ionic, hydrogen, disulfide, and hydrophobic interactions between amino acid side chains.
- Triglyceride
- A lipid formed from glycerol and three fatty acids joined by ester bonds; it is a compact energy store and is insoluble in water.
- Phospholipid
- A lipid with a hydrophilic phosphate head and two hydrophobic fatty acid tails, which arranges into bilayers in water.
- Benedict's test
- A test for reducing sugars in which the sample is heated with Benedict's reagent; a brick-red precipitate indicates a positive result.
- Biuret test
- A test for proteins in which Biuret reagent is added; a purple colour indicates the presence of peptide bonds.
- Enzyme active site
- The specific region of an enzyme where the substrate binds, forming an enzyme-substrate complex and lowering the activation energy of the reaction.
- Denaturation
- Loss of an enzyme's three-dimensional shape and active site caused by high temperature or extreme pH, so the substrate can no longer bind.
- Competitive inhibition
- An inhibitor binds the active site and competes with substrate; its effect is reduced by increasing substrate concentration.
- Non-competitive inhibition
- An inhibitor binds away from the active site and changes enzyme shape; increasing substrate concentration does not overcome the inhibition.
- DNA base pairing
- Adenine pairs with thymine by two hydrogen bonds, and guanine pairs with cytosine by three hydrogen bonds in double-stranded DNA.
- Semi-conservative replication
- DNA replication in which each daughter molecule contains one original strand and one newly synthesised strand, following complementary base pairing.
- Transcription
- The synthesis of messenger RNA from a DNA template strand by RNA polymerase, occurring in the nucleus of eukaryotic cells.
- Translation
- The assembly of amino acids into a polypeptide at the ribosome, guided by mRNA codons matched to tRNA anticodons.
- Genetic code properties
- The code is triplet, degenerate, non-overlapping, and universal; each codon specifies one amino acid, though several codons may code for the same amino acid.
- Mitosis
- Nuclear division producing two genetically identical diploid daughter cells, used for growth, repair, and asexual reproduction.
- Meiosis
- Two successive nuclear divisions producing four genetically varied haploid cells, involving crossing over and independent assortment of homologous chromosomes.
- Test cross
- A cross between an individual of unknown genotype and a homozygous recessive individual, used to reveal whether the unknown was homozygous or heterozygous.
- Binomial nomenclature
- A two-part naming system for species using the genus and species names, written in italics with the genus capitalised.