The name is absent

When cortical pyramidal cells are stained using the immunohistochemical
methods we observe that long apical dendrites are extended toward the surface
cortical layer and basal dendrites are extended in all directions in the area
adjacent to the soma. Dendrites can be thought of as extensions of the cell body
with maximal length ~ 1-2 mm in the largest neurons (Fiala & Harris, 1999),
which provide increased surface area at much lower cell volumes. For example,
97% of the surface area of a motor neuron (excluding the axon) is dendritic
(Ulfhake & Kellerth, 1981). The dendrites have 3.7x105 μm² of surface area while
occupying only 3x105 μm³. To provide an equivalent surface, a spherical cell
body would be 340 μm in diameter and consume 2x10⁷ μm³. The fact that 80% of
the surface area of proximal dendrites of motor neurons are covered with
synapses (Kellerth et al., 1979) suggests that this increased surface area is
indeed valuable for increasing the number of inputs to a neuron.

The most common synaptic specializations of dendrites are simple spines.
Spines are protrusions from the dendrite of usually no more than 2 μm, often
ending in a bulbous head attached to the dendrite by a narrow stalk or neck.
Spine heads usually have diameter ~ 0.6 μm; when this diameter is exceeded we
speak about mushroom spines. The spines are usually pedunculated (i.e. they
have narrow neck) but sessile spines with no neck are also known. The total
spine length for CA1 pyramidal neuron is 0.2-2μm, neck diameter 0.04-0.5μm,
neck length 0.1-2μm, total spine volume 0.004-0.6μm³, total surface area of a
single spine 0.1-4μm², postsynaptic density (PSD) area 0.01-0.5μm².

Neurons are classified as spiny, sparsely spiny, and nonspiny (or smooth)
according to the density of simple spines on their dendrites (Peters & Jones,
1984). Such a classification is complicated by the fact that different dendrites of a
given neuron may exhibit widely different spine densities (Feldman & Peters,
1978). Even along the length of a dendritic segment, spine densities can vary
widely. Nominally nonspiny dendrites often exhibit a few simple spines.

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