Sebaceous gland

Sweat glands are morphologically simple tubular unbranched glands!

They consist of a long excretory duct, which opens with sweat pore on the surface of the skin and the secretory portion, which is also long, twisted into a glomerulus and is located deeply in the dermis.

Sweat glands are divided into two types: merocrine and apocrine.

They are similar in structure, but have a number of features:

Merocrine are smaller in size, they begin to secrete sweat immediately after birth, their glandular cells are not destroyed when secretion is excreted!

Apocrine is larger in size than merocrine, they begin to function only with the onset of puberty in the presence of sex gormons, when secretion is excreted, the apical section of glandular cells is destroyed and these glands are located in the regions of axilla, in the forehead, perineum, and genital organs!

Secretoty portions of sweat glands consist of secretory cells ( light and dark in merocrine. Cuboidal in apocrine) and myoepithelial cells!

Sebaceous glands are morphologically simple alveolar branched!

They are characterized by a holocrine type of secretion!

They consist of an excretory duct that is connected to the hair and a secretory portion in the dermis!

The secretory portion secretes sebum and consists of sebocyte cells.

There are three types of sebocytes:
-Basal - lie on the basement membrane and divide mitotically, form a growth layer. -Differentiated - cells synthesizing components of sebum, organelles are well developed in them.
-Necrotic cells are cells that break down and secrete sebum.

Sebum makes the skin more elastic and protects it from microorganisms.

Sebaceous gland

The nail is a derivative of the skin and consists of the nail plate and the nail bed!
The nail plate is the stratum corneum of the epidermis. The keratinocytes of the nail plate contain hard keratin!
The nail plate lies on the nail bed! The nail bed - consists of the dermis + basal and spinosum layers of the epidermis (these are the growth layers)!
The nail plate is divided into root, body and edge.
The root of the nail is the back of the nail plate. Edge - the free end of the plate, protruding beyond the nail bed. The epithelium of the nail bed on which the root of the nail lies is called the nail matrix. In it, epithelial cells are constantly dividing and keratinizing! The resulting horny scales are displaced into the nail plate, which as a result increases in length, that is, the nail grows!

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