Rosette (botany) Rosette (botany) In botany, a rosette is a circular arrangement of leaves or of structures resembling leaves. In flowering plants, rosettes usually sit near the soil, their structure is an example of a modified stem in which the internode gaps between the leaves do not expand, so that all the leaves remain clustered tightly together and at a similar height. In bryophytes and algae, a rosette results from the repeated branching of the thallus as the plant grows, resulting in a circular outline. Many plant families have varieties with rosette morphology; they are particularly common in Asteraceae (such as dandelions),
Calyx of Held third postnatal weeks, around the time of hearing onset, the calyx of Held develops its characteristic, highly fenestrated (many openings) appearance. Fenestration results in the membrane being reduced to numerous small compartments, which increase surface area of the presynaptic cleft. As the membrane becomes increasingly pinched into these bulb-like structures, synaptic vesicles are further grouped into these spaces, resulting in an increased number of docked vesicles. To compensate for the available spaces in the calyx, glial cells with glutamate receptors and transports are used to fill open spaces, ensuring efficient uptake of glutamate in the synapse. This physical change in