Lecture 5 study guide

Question 1

describe the components and primary function of the integumentary system

Answer 1

• Protection – gives the barrier to protect the body from water loss, invading pathogens, UV radiation, and physical issues
• Temperature regulation – if too cold, the body’s temp is maintained through skin and hair. If too hot the body releases sweat
• Sensory reception – allows us to feel things
• Vitamin D synthesis

Question 2

explain the process and importance for calcium absorption

Answer 2

• When sunlight hits the skin, modified cholesterol molecules are converted to a vitamin D receptor. Without proper access to sunlight health can decline
• Vitamin D is necessary for calcium absorption
• Lack of vitamin D during development can cause rickers

Question 3

epidermis

Answer 3

superficial -> the thin wavy base. Is stratified squamous

Question 4

dermis

Answer 4

the deeper layer -> where we see the nerves, follicles, and parts

Question 5

hypodermis

Answer 5

the subcutaneous layer -> in charge of insulation, energy storage, and adipose tissues

Question 6

the four cell types of the epidermis

Answer 6

• Keratinocytes – the most abundant cell type, produce keratin and a tough fibrous protein. (as cells fill with keratin they die)
• Melanocytes – found in the deepest layer of the epidermis and produce melanin. When in contact with the skin more melanin is produced to protect the lower skin tissues
• Dendritic (Langerhans) cells – like macrophages; help fight of pathogens, has pathogens that help kill things by invading the skin
• Tactile (merkel) cells – they are between the epidermis and dermis, allows you to feel light touches on the skin. Fingertips are an area with a lot of these

Question 7

the five layers of the epidermis

Answer 7

• Stratum corneum – the top layer made of dead keratinocytes
• Stratum lucidum – (only found in thick skin), the clear layer, is 2-3 layers, and is on the hands and feet
• Stratum granulosum – has 1-5 layers, is where keratin building begins
• Stratum spinosum – the spiny layer – living keratinocytes (has desmosomes)
• Stratum basale – is the bottom layer. The layer of the base of the dermis. Where stem cells that rapidly divide and create new ones

Question 8

basal cell carcinoma

Answer 8

makes up about 80% of cases, is most commonly seen on the face, is a proliferation of the stratum basale cells, is the least malignant and most common one, 99% of these can be surgically removed

Question 9

squamous cell carcinoma

Answer 9

on the head, face; and nails. Is proliferation of keratinocytes in the stratum spinosum. The 2nd most common form, can metastasize if not treated in time

Question 10

melanoma

Answer 10

the most dangerous type and is 2-3% of all cases. The proliferation of melanocytes is highly metastatic and resistant to chemo. Early detection is key