Unformatted text preview:

BSCI 201Review Sheet for Exam 2A. The Integumentary system:1. Name and describe all the strata in the epidermis of a thin layer and a thick layera. from deep to superficial:i. Stratum basale – single layer of cuboidal cells called keratinocytes. Always undergoing mitosis (mitotically active). Contains melanocyteswhich produces melanin and it protects the skin from UV radiation.ii. Stratum spinosum – several layers of cells joined by desmosomes. Cells appear spiny because of the intermediate filaments called tonofilaments and they can withstand pulling forces without the cells separating.iii. Stratum granulosum – 3-5 layers of flattened cells filled with granules(2 types: keratohyaline granules and lamellated granules)iv. Stratum lucidum (found only in thick skin) – 3-5 layers of dead cells, appears translucent under a light microscopev. Stratum corneum – 20-30 layers of dead flattened squamous-like cells. The dead cells are filled with keratin which makes it abrasive-resistant. The cells are also coated with gylcolipids making the skin waterproof2. Describe the following: tonofilaments, Langerhan’s cells, lamellated granules, keratohyaline granulesa. Tonofilaments – supports and connects the cells to prevent separation letting in pathogens. Found in stratum spinosum b. Langerhan’s cells (epidermal dendrite cells) – act as macrophages in epidermic to engulf or destroy pathogens and to activate specific immune responses if the pathogen gains access into the body. Mostly found in stratumspinosumc. Lamellated granulesd. Keratohyaline granules – keratinization of the skin which makes the skin water proof. Found in the stratum granulosum.3. Name and describe the two layers in the dermisa. Superficial papillary layer – Highly vasculared areolar connective tissue. Surface of the papillary layers is thrown into involutions called dermal papillae. Dermal papillae contains 3 structures: blood vessels, free nerve ending (pain receptors), and meissner’s corpuscles (touch receptors)b. Deep reticular layer (stratum reticulerosum) – dense irregular connective tissue and dense collagen fibers. It strengthens the skin structural and elastically. 4. Describe the following: Meissner’s corpuscles, Pacinian corpuscles, Merkel discsa. Meissner’s corpuscles – light touch receptors in papillary layer of the dermisb. Pacinian corpuscles – deep pressure receptor in reticular layer of the dermisc. Merkel discs – light touch receptors in epidermal-dermal junctions. This is thecombination of free nerve endings and merkel cells. Merkel cells alone cannot transmit impulses so they are not nervous structures. 5. Name and discuss the function of the accessory skin structures. What is acid mantle?a. Sweat glands i. Ecrrine (mesocrine sweat glands) - simple coiled tubular multicellular exocrine gland. It secretes sweat via the merocrine mod of secretion. Sweat prevents the growth of microorganism on the surface of the skin. Located in palms, soles, and foreheadii. Apocrine (ordiferous gland) – located in annogential and axillary (armpit) areas. Activated after puberty. The secreted product itself does not stink, but does emit an odor when combined with the bacteriapresent on the skin. Secrete, viscous yellowish fluid onto hair folliclesiii. Ceruminous glands – specialized sweat glands located in the lining of the external ear canal. Secrete a bitter substance called cerumen (earwax) to prevent entry of foreign objects such as insects and water into the ear.iv. Mammary glands – specialized sweat glands in breasts that secrete milk to feed the youngb. Sebaceous gland (oil glands) – simple alveolar glands. Located everywhere inbody except in palms/soles. Secretes sebum into hair follicles and via pores tothe surface of the skin to keep the hair/skin moisturized (oily) to prevent water lossc. Hairs/pili – protects against trauma and insulates the body in cold weatheri. 2 regions1. Shaft – above skin surface. Flat or ribbon-like is curly hair. Oval is wavy hair. Round is straight hair. Highly keratinized dead cells2. Root – below skin surface enclosed in hair follicle. Hair follicle also contains hair matrix. Cells in the matrix constantlyundergo mitosis forming 3 concentric rings (medulla, cortex, and cuticle) The base of hair follicles re wrapped by root hair plexus which acts like touch receptors when hair is bentd. Acid mantle – sweat contributes to the protective function of the skin. Skin pH level is between 4-6 levels. It is a very fine slightly acidic film (sweat) covering the skin to protect it from microorganisms 6. Name and discuss the 3 types of burnsa. First degree burn (partial thickness burn) – damage to the epidermis and no treatment necessaryb. Second degree burn (partial thickness burn) – damage to papillary layer of dermis; blister formationc. Third degree burn (full thickness burn) – destruction of entire epidermis and dermis and occasionally hypodermis; intermediate treatment necessary to prevent pathogenic infection and to supply water and electrolytes lost in the burn due to loss of epidermis7. Name and define the 3 major types with skin cancera. Basal cell carcinoma – proliferation in stratum basale; least malignant and most common; slow growthb. Squamous cell carcinoma – stratum spinosum; second most common; grows rapidlyc. Melanoma – proliferation of the melanocytes (cell producing melanin, which provides protection against UV radiation); most aggressive; highly metastatic and resistant to chemotherapy; least common B. Skeletal System: 1. Compare and contrast compact and spongy bone tissues.a. Compact bone- is located on the exterior part of bone Compact bones are composed of osteons. Has concentric rings called lamellae; haversian canal = center of osteon and contains blood vessels. b. Spongy bone - is located in the interior part of bone. Composed of needle-like structure called trabeculaec. Both contain blood vessels2. Name and describe the 4 structural classes of bones: What are sesamoid bones? Give an example of each class. a. long bones – composed of diaphysis (shaft) and 2 epiphysis (expanded ends of thelong bones) at the end of epiphyseal plates in children show remnants of hyaline cartilage. Mostly in the appendicular skeleton (phalanges are long bones too) i. surrounded by medullary cavity:1. red bone marrow (in children) – produces blood cells and platelets in children2. yellow bone marrow (in adults) – does


View Full Document

UMD BSCI 201 - Review Sheet for Exam 2

Documents in this Course
Tissues

Tissues

3 pages

Exam 1

Exam 1

19 pages

Exam 1

Exam 1

106 pages

Tissues

Tissues

2 pages

Chapter 1

Chapter 1

29 pages

BONES

BONES

9 pages

Notes

Notes

2 pages

Notes

Notes

2 pages

EXAM 3

EXAM 3

6 pages

EXAM 3

EXAM 3

7 pages

EXAM 2

EXAM 2

16 pages

EXAM 3

EXAM 3

6 pages

Muscles

Muscles

10 pages

Exam 2

Exam 2

16 pages

Exam 2

Exam 2

21 pages

Exam 2

Exam 2

17 pages

Notes

Notes

68 pages

Notes

Notes

2 pages

Famine

Famine

1 pages

Notes

Notes

6 pages

Exam 2

Exam 2

48 pages

Load more
Download Review Sheet for Exam 2
Our administrator received your request to download this document. We will send you the file to your email shortly.
Loading Unlocking...
Login

Join to view Review Sheet for Exam 2 and access 3M+ class-specific study document.

or
We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view Review Sheet for Exam 2 2 2 and access 3M+ class-specific study document.

or

By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?