See pulse.
A type of racemose inflorescence in which stalkless flowers arise from an undivided floral axis, as in plantain and Orchis. In the family Gramineae (Poaceae; sedges and grasses) the flowers are grouped in clusters called spikelets (see illustration), which may be arranged to form a compound spike (as in wheat). See glume; lemma.
Spike: structure of a spikelet
A solution (liquid or gaseous) containing a known concentration of a particular element whose isotopic concentration has been changed by the enrichment of one of its naturally occurring isotopes. The spike is used in isotope dilution analysis, being mixed in known proportions with the sample solution, prior to isotopic determination by means of a mass spectrometer (see mass spectrometry).
- Afghani, Jamal al‐Din al‐ (1839–97)
- Afghanistan
- Afghan Wars
- AFIPS
- AFL
- aflatoxin
- AFLP
- AFM
- AFMAG EM system
- AFM diagram
- afocal
- a fortiori
- Africa
- African Charter on Human and Peoples’ Rights
- African National Congress
- African Network Information Centre
- African Plate
- African Union
- Afrikaner
- AFRINIC
- AFTE
- afterbirth
- afterglow
- after-heat
- after-image