Dictionary > Stratum spinosum

Stratum spinosum

Definition
noun
The thin layer of the epidermis between stratum basale and stratum granulosum, and comprised of distinctive keratinocytes (called prickle cells)
Supplement
In animals, such as vertebrates, the epidermis is made up of four or five layers (each called stratum). These layers protect the underneath layers of the skin against physical damage, infection, and water loss. In humans, the epidermis consists of the following layers: (1) stratum corneum, (2) stratum lucidum, (3) stratum granulosum, (4) stratum spinosum, and (5) stratum basale or germinativum).

The stratum spinosum is a Latin term, which literally means spinous layer. This layer is found in in between the stratum basale and the stratum granulosum. The keratinocytes in the stratum spinosum are referred to as prickle cells. These keratinocytes are polyhedral in shape and with large pale-staining nuclei.

They are actively synthesizing fibrillary proteins that are essential for the formation of desmosomes. The desmosomes anchor the cells to each other and strongly connect the cells together. During tissue fixation for histologic microscopy, the cells tend to shrink but remain tightly bound to each other through the desmosomes and thereby the sites of connection between cells appear like spines or prickles (hence, the name). Langerhans cells are also found in the stratum spinosum. Keratinization begins in this layer.
Synonym(s):

  • spinous layer (of the epidermis)
  • prickle cell layer

See also:


You will also like...

Control of body movement
Control of Body Movement

Some of the body movements can be controlled at will, others cannot. The body has a motor program, which is the pattern ..

Gene Regulation in Eukaryotes
Gene Regulation in Eukaryotes

Learn about the general structure of a eukaryotic gene, the transcription factors, and post-transcriptional regulation....

Neural Control Mechanisms
Neural Control Mechanisms

Neurons generate electric signals that they pass along to the other neurons or target tissues. In this tutorial, you wil..

Human Neurology
Human Neurology

Human Neurology deals essentially with the nervous system of humans. It also features the various theories put forward b..

Carbohydrates, fats and proteins - dietary sources
A Balanced Diet – Carbohydrates and Fat

Apart from vitamins, the human body also requires high energy sources such as carbohydrates and fats. If you want an ove..

Ploidy
Polyploidy

Humans are diploid creatures. This means that for every chromosome in the body, there is another one to match it. Howeve..

Related Articles...

No related articles found

See all Related Topics