In which specimen were cells first identified? A. microorganism B. cork bark

In which specimen were cells first identified?

A. microorganism

B. cork bark

C. DNA

D. mitochondria

Answer – B. cork bark.

Cells were first identified by Robert Hooke within cork in the year 1665 by using the microscope. Robert Hooke had noticed that cork was developed by using various small units which looked like the small rooms or the cells in which the monks within a monastery lived. The small units were named as corks as these reminded Robert Hooke of the cellula or the small rooms. The structure of the cork was examined based on greater levels of accuracy by using the different imaging techniques. The further investigations also provided new insights based on the appropriate structure that has been developed by the cork and the differences that exist between cells of phellem and the cells that are bordering the lenticels. Cell differentiation based on lenticular phellogen had been effectively restricted to a single layer of cells that leads to the cell wall which is considered to be many times thicker for the lenticels (Crouvisier-Urion, K. et al. 2019). Different composition is also displayed due to the high content of lignin within lenticels. The advancement in knowledge of composition and structure of the cork cells can provide major levels of contributions towards improved understanding of microporosity of the cork. Cork has been mainly described as the alveolar material that mainly consists of the empty and dead closed cells. This mainly corresponds to bulk part of cork tissues that include the lenticels which are considered to be open microporous cells. Cork tissues are considered to be phellem as a part of the present work (Crouvisier-Urion, K. et al. 2019). Hooke has provided information based on only a single orientation of the cork cells based on two different directions. The 3D structure was highlighted later on by the other authors.