A LEVEL BIOLOGY KEY TERMS Flashcards
What is aminoacylase?
Enzyme used to produce samples of L-amino acids
What are abiotic factors?
Non-living conditions in a habitat
What is abscission?
Fall of leaves
What is acetyl coenzyme A?
Molecule that enters Krebs cycle from glycolysis through linking reaction, coenzyme A combines with an acetyl group
What is acetylation?
Addition of acetyl group
What is an action potential?
Change in potential difference across the neurone membrane of the axon when stimulated (appox. +40mV)
What is activation energy?
Energy required to initiate a reaction
What is an active site?
Area of an enzyme complementary to a specific substrate, allowing enzyme to bird to a substrate with specificity
What is active transport?
Movement of particles across a plasma membrane against concentration gradient - energy is required
What is ADP?
- Nucleotide made of adenine, pentose sugar and 2 phosphate groups
- formed by hydrolysis of ATP, releasing a phosphate ion and energy
What is ATP?
- Nucleotide made of adenine, pentose sugar and 3 phosphate groups
- universal energy currency for cells
What are agglutinins?
Chemicals (antibodies) that cause pathogens to clump together so can be engulfed by pathogens easier
What is alcoholic fermentation?
Fermentation that results in production of ethanol
What are alkaloids?
Bitter-tasting compounds found in plant leaves that may affect metabolism of animals eating plant/poisoning them
What is an allele?
A version of a gene
What is allele frequency?
Relative frequency of a particular allele in a population at a given time
What is allopatric speciation?
Speciation that occurs as a result of a physical barrier between populations
What are amino acids?
Monomer used to build polypeptides and therefore proteins
What is ammonification?
Conversion of nitrogen compounds in dead matter or waste into ammonium compounds by decomposers
What are anabolic steroids?
Steroid drugs used by athletes to increase muscle mass
What does anabolic mean?
- Reactions of metabolism that construct molecules from smaller units
- reactions require envy from hydrolysis of ATP
What is anaerobic respiration?
Respiration in absence of oxygen
What are analogous structures?
Structures adapted to perform same function but have a different origin
What is anaphase?
3rd stage of mitosis where chromatids are separated to opposite poles of me cell
What are antibiotic resistant bacteria?
Bacteria that undergo mutation to become resistant to an antibiotic and then survive to increase in number
What are antibiotics?
A chemical or compand that kills / inhibits grown of bacteria
What are antibodies?
Y -shaped glycoproteins made by B cells of me immune system in response to antigen
What is ADH?
Hormone that increases permeability of distal convoluted tubule and collecting duct to water
What is an antigen?
Identifying chemical on surface of cell to trigger an immune response
What is an antigen-antibody complex?
Complex formed when an antibody and antigen bind
What is an antigen-presenting cell (APC)?
A cell that displays foreign antigens complexed with histocompatibility (tissue compatability) complexes on their surfaces
What is the antisense strand?
Strand of DNA that runs 3’ to 5’ and is complementary to sense strand
- acts as template stand during transcription
What are anti-toxins?
Chemicals (antibodies) that bind to toxins produced by pathogens so they no longer have an effect