QUESTIONS WITH 100% CORRECT ANSWERS
Functions of the Integumentary System - correct answer--Resistance to trauma and infection
-Prevents loss or gain of water
-Vitamin D synthesis
-Sensory receptors for heat, cold, touch, texture, pressure, vibration, and tissue injury
-Thermoregulation
How does skin resist trauma and infection? - correct answer--
Skin has low pH to reduce bacteria and fungi
-Cells are packed closely together with tough protein called keratin
Name 3 ways the integumentary system thermoregulates? - correct answer--
Glands release sweat for evaporative cooling
- Vasoconstriction
- Vasodilation
Define: Vasoconstriction - correct answer-narrowing of blood vessels, reduces heat loss
Define: Vasodilation - correct answer-widening of blood vessels, increases heat loss
What are the 2 main parts of the integumentary system? - correct answer-Epidermis- outer layer
Dermis- underlying connective tissue
*Hypodermis not really part of the skin!*
What does the epidermis primarily consist of? - correct answer-
keratinized stratified squamous epithelium
What are the epidermal derivatives? - correct answer-glands, hair, nails
,What are the 4 main cell types in the epidermis? - correct answer-- Karatinocytes
- Melanocytes
- Tactile (Merkel) cells
- Dendritic (Langerhans) cells
Keratinocytes (functions) - correct answer-most numerous cell type, make fibrous protein keratin
Melanocytes (functions) - correct answer-synthesize pigment called melanin
Tactile cells (functions and 2nd name) - correct answer-
also called Merkel cells, receptors for the sense of touch, associated with a dermal nerve fiber
Dendritic cells (functions and 2nd name) - correct answer-
macrophages (big phagocytic cells) that kill microbes
What are the layers of the epidermis (list from bottom up)? - correct answer-- Stratum basale
- Stratum spinosum
- Stratum granulosum
- Stratum lucidum
- Stratum corneum
What layer of the epidermis is only found in thick skin? - correct answer-Straum lucidum
How many layers are found in the stratum basale? - correct answer-1 layer
What cells are found in the stratum basale? - correct answer-
stem cells, keratinocytes, melanocytes, tactile (merkel) cells
What is the importance of the stem cells in the stratum basale? - correct answer-
makes it mitotically active, the stem cells divide and give rise to keratinocytes
, How many layers are in the stratum spinosum? - correct answer-8-10 layers
What is the appearance of the cells in the stratum spinosum, and why? - correct answer-
The cells are flattened, which happens as they are pushed upward
What is contained in the stratum spinosum? - correct answer-
Keratinocytes, dendridic (langerhans) cells
In which epidermis layers do keratinocytes produce waterproofing substances? - correct answer-
Stratum spinosum, stratum granulosum
What are the waterproofing substances produced by the keratinocytes? - correct answer-keratin, lipids
How many layers are in the stratum granulosum? - correct answer-3-5 layers
In what layer do the nuclei and organelles begin to degenerate in the keratinocytes? - correct answer-
stratum granulosum
What do the cells look like in the stratum granulosum and why? - correct answer-
They continue to flatten because of accumulation of keratin
How many layers are in the stratum lucidum, and what do they look like? - correct answer-3-
4 layers of translucent cells
Why are the cells in the stratum lucidum translucent? - correct answer-the clear protein named eleidin
How many layers are in the stratum corneum? - correct answer-up to 30 layers
What do the layers of the stratum corneum consist of? - correct answer-dead scaly keratinized cells
What are 2 of the main purposes of the stratum corneum? - correct answer-
resistance to abrasion and water loss