biology-dictionary_11-06-2009

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Koch's postulates
A set of four criteria for determining whether a specific pathogen is the cause of a disease.
Krebs cycle
A chemical cycle involving eight steps that completes the metabolic breakdown of glucose
molecules to carbon dioxide; occurs within the mitochondrion; the second major stage in
cellular respiration.


L


Lacteal


A tiny lymph vessel extending into the core of an intestinal villus and serving as the
destination for absorbed chylomicrons.
Lagging strand
A discontinuously synthesized DNA strand that elongates in a direction away from the
replication fork.
Lamella
Layer, thin sheet.
Lamina
A thin plate or layer (especially of bone or mineral).
Larva
A free-living, sexually immature form in some animal life cycles that may differ from the
adult in morphology, nutrition, and habitat.
Lateral line system
A mechanoreceptor system consisting of a series of pores and receptor units (neuromasts)
along the sides of the body of fishes and aquatic amphibians; detects water movements
made by an animal itself and by other moving objects.
Lateral meristem or seconadary meristem
The vascular and cork cambium, a cylinder of dividing cells that runs most of the length of
stems and roots and is responsible for secondary growth.

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