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for some of the biochemical activities of the
cell. In the liver cells of the group of animals Camillo Golgi was born at
Corteno near Brescia in
called vertebrates (see Chapter 7), SER plays
1843. He studied
a crucial role in detoxifying many poisons medicine at the University
and drugs.
of Pavia. After graduating
in 1865, he continued to
work in Pavia at the
Hospital of St. Matteo. At
that time most of his
investigations were
concerned with the nervous system, In 1872
he accepted the post of Chief Medical Officer
at the Hospital for the Chronically Sick at
Abbiategrasso. He first started his
investigations into the nervous system in a
little kitchen of this hospital, which he had
converted into a laboratory. However, the
work of greatest importance, which Golgi
carried out was a revolutionary method of
staining individual nerve and cell structures.
This method is referred to as the ‘black
reaction’. This method uses a weak solution
of silver nitrate and is particularly valuable
in tracing the processes and most delicate
ramifications of cells. All through his life,
he continued to work on these lines,
modifying and improving this technique.
Fig. 5.6: Plant cell Golgi received the highest honours and
awards in recognition of his work. He shared
the Nobel prize in 1906 with Santiago
5.2.5 (ii) GOLGI APPARATUS Ramony Cajal for their work on the structure
of the nervous system.
The Golgi apparatus, first described by
Camillo Golgi, consists of a system of
membrane-bound vesicles (flattened sacs) 5.2.5 (iii) LYSOSOMES
arranged approximately parallel to each other
in stacks called cisterns. These membranes Structurally, lysosomes are membrane-bound
often have connections with the membranes sacs filled with digestive enzymes. These
of ER and therefore constitute another portion enzymes are made by RER. Lysosomes are a
of a complex cellular membrane system. kind of waste disposal system of the cell. These
The material synthesised near the ER is help to keep the cell clean by digesting any
packaged and dispatched to various targets foreign material as well as worn-out cell
inside and outside the cell through the Golgi organelles. Foreign materials entering the cell,
such as bacteria or food, as well as old
apparatus. Its functions include the storage, organelles end up in the lysosomes, which
modification and packaging of products in break complex substances into simpler
vesicles. In some cases, complex sugars may
substances. Lysosomes are able to do this
be made from simple sugars in the Golgi because they contain powerful digestive
apparatus. The Golgi apparatus is also enzymes capable of breaking down all organic
involved in the formation of lysosomes [see material. During the disturbance in cellular
5.2.5 (iii)]. metabolism, for example, when the cell gets
56 SCIENCE
Rationalised 2023-24
