Biology Dictionary

  • Law of conservation of matter

    Law of conservation of matter

    A principle stating that matter cannot be created or destroyed in a chemical reaction.

  • Law of definite proportions

    Law of definite proportions

    A chemical law stating that a given chemical compound always contains its elements in the same proportion by mass.

  • Law of dominance

    Law of dominance

    A principle of inheritance stating that in a heterozygote, the dominant allele will express its trait over the recessive allele.

  • Law of independent assortment

    Law of independent assortment

    Mendel’s principle stating that alleles for different traits are inherited independently of each other.

  • Law of segregation

    Law of segregation

    Mendel’s law stating that allele pairs separate or segregate during gamete formation, and randomly unite at fertilization.

  • Lawn

    Lawn

    A dense layer of bacterial growth on an agar plate, typically used in experiments to measure the spread of a pathogen.

  • Layering

    Layering

    A method of plant propagation where a stem is encouraged to root while still attached to the parent plant.

  • Lcat

    Lcat

    Lysophosphatidylcholine acyltransferase, an enzyme involved in the metabolism of lipids.

  • Ld50

    Ld50

    The lethal dose of a substance required to kill 50% of a population, commonly used in toxicology studies.

  • Ldh

    Ldh

    Lactate dehydrogenase, an enzyme involved in the conversion of lactate to pyruvate in anaerobic metabolism.