What makes up the integumentary system?
-the skin
-hair
-oil
-sweat glands
-nails
-sensory receptors
What are the 2 parts that structurally makes up the skin?
- The epidermis= the superficial, thinner portion, composed of epithelial tissue
- The dermis= the deeper, thicker portion made of dense irregular connective tissue
What are the 4 types of cell contained in the epidermis skin layer?
- keratinocytes (protein keratin)
- Melanocytes (pigment melanin)
- Intraepidermal macrophages (immune responses)
- Tactile epithelial cells (detect touch sensations)
What are the 5 layers of the epidermis skin layer?
- stratum corneum (most superficial layer)
- stratum lucidum (thick, hairless skin only)
- stratum granulosum (keratinocytes undergo apoptosis here)
- stratum spinosum (provides strength and flexibility)
- stratum basale (deepest layer)
What is the superficial part of the dermis made up of?
areolar connective tissue containing fine elastic fibres
What increases the dermis surface area?
-small fingerlike projections (dermal papillae), touch receptors and free nerve endings
What makes up the deeper part of the dermis?
-dense irregular connective tissue containing bundles of collagen and some coarse elastic fibres
What are found between the fibres in the deeper part of the dermis?
-adipose tissue
-hair follicles
-nerves
-oil glands
-and sweat glands
What are the three main pigments that impact a variety of skin colours?
-melanin
-haemoglobin
-carotene
Give 3 examples of accessory structures of the skin and what their role is
-hair and nails= protect the body
-sweat glands help regulate body temperature
What skin surfaces are hairs or pili NOT present on?
-palms
-palmar surfaces of the fingers
-soles
-plantar surfaces
What are hairs and what are they made up of?
-a thread of fused, dead, keratinised epidermal cells
-consists of a shaft, a root and follicle
What is the role of subaceous glands?
-connected to hair follicles
-produce sebum which moistens hairs and waterproofs the skin, keeps the skin soft and inhibits certain bacteria
What are ceruminous glands?
-present in outer ear canal is a yellowish secretion called cerumen or earwax
What are the two types of sudoriferous glands?
- apocrine sweat glands= found mainly in the skin of the armpit, groin, areolae of the breasts and bearded regions of the face
- eccrine sweat glands= most prevalent sweat glands distributed throughout most of the body, especially in the skin of the forehead, palms and soles
What are the main functions of the skin?
-protection from UV light, dehydration, microbes,
-regulation of heat
-produce vitamin D
-shock absorber
What are the (7) parts of a nail?
- the free edge (extends past finger)
- the nail body (visible portion of nail)
- lunula (thick white part)
- cuticle (the stratum corner of the epidermis)
- nail root (portion which isn’t visible)
- nail matrix (contains dividing cells which produce new nail cells)
- nail bed (attaches free edge to fingertip)
