{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

9.4.09 integumentary system

9.4.09 integumentary system - 1 The Integumentary System o...

Info icon This preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
The Integumentary System o Skin and its accessory structures -structure -function -growth and repair -development -aging -disorders General Anatomy o A large organ composed of all 4 tissue types (epithelial, muscle, connective, neural) o Covers outside of animal o Continuous with mucous membranes at oral, anal and urogenital orifices, nostril, and the palpebral fissure (located at eye) via mucocutaneous junction Overview o 2 Major layers of skin -epidermis is epithelial tissue only -dermis is layer of connective tissue, nerve, and muscle o Subcutaneous tissue (subQ or hypodermis) is layer of adipose & areolar tissue -subQ = subcutaneous injection -intradermal = within the skin layer Overview of Epidermis o Stratified squamous epithelium Contains no blood vessels 4 types of cells 4 distinct strata (layers of cells) Cell types of the Epidermis o Keratinocytes--90% -produces keratin o Melanocytes-----8 % -produces melanin pigment -melanin transferred to other cells with long cell processes o Langerhan cells -from bone marrow -provide immunity 1
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
o Merkel cells -in deepest layer of epidermis -form touch receptors with sensory neuron Layers (Strata) of the Epidermis o Stratum corneum o Stratum lucidum o Stratum granulosum o Stratum spinosum o Stratum basale Stratum Basale o Deepest single layer of cells Called stratum germinativum Combination of merkel cells, melanocytes, keratinocytes and stem cells that divide repeatedly Cells attach to each other and to the basement membrane by the use of desmosomes and hemidesmosomes Stratum Spinosum o 8 to 10 cell layers held together by desmosomes During slide preparation, cells shrink and look spiny Melanin taken in by phagocytosis from nearby melanocytes Stratum Granulosum o 3 - 5 layers of flat dying cells Show nuclear degeneration Contain dark-staining keratohyalin granules Contain lamellar granules that release lipid that repels water (makes our skin repellant to water) Stratum Lucidum o Seen in thick skin on palms & soles of feet Three to five layers of clear, flat, dead cells Contains precursor of keratin 2
Image of page 2
Stratum Corneum o 25 to 30 layers of flat dead cells filled with keratin and surrounded by lipids Continuously shed Barrier to light, heat, water, chemicals and bacteria Friction of these cells stimulates callus formation Keratinization & Epidermal Growth o Stem cells divide to produce keratinocytes As keratinocytes are pushed up towards the surface, they fill with keratin
Image of page 3

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern