Review Questions Integumentary System
BIO 137
Human Anatomy and Physiology I
Chapter 5 -- Review Questions
1. Describe the hypodermis. Is it part of the skin?
Yes, it’s part of the skin. The hypodermis is the innermost and thickest layer of the skin. It cushions the body and helps regulate skin and body temperature.
2. Describe the composition of the epidermis.
The epidermis is made up of Stratified Squamous Epithelium.
3. Name and discuss the four cell types found in the epidermis. (Give the structure and function of each) * Keratinocytes- 90% filled with keratin and have a waterproof barrier. * Melanocytes- 8% produce melanin pigment and pass them to the keratinocytes. * Langerhans cells- phagocytes from the immune system and are easily damaged by UV light * Merkle cells- located in deepest layer of hairless skin and they are the sensory transduction.
4. Name the five epidermal layers from the outside of the skin to the inside. Tell the structure of each. * Stratum Corneum- Most superficial layer; 20–30 layers of dead cells represented only by flat membranous sacs filled with keratin. Glycolipids in extracellular space. * Stratum Lucidum- Clear, translucent layer. Only found in palms and soles. * Stratum granulosum- Three to five layers of flattened cells, organelles deteriorating; cytoplasm full of lamellated granules (release lipids) and keratohyaline granules. * Stratum spinosum- Several layers of keratinocytes unified by desmosomes. Cells contain thick bundles of intermediate filaments made of pre-keratin. * Stratum basale- Deepest epidermal layer; one row of actively mitotic stem cells; some newly formed cells become part of the more superficial layers. See occasional melanocytes and epidermal dendritic cells.
5. Describe the composition of the dermis layer.
Dense irregular fibrous connective tissue.
6. Name and discuss the two layers of the dermis. * Papillary region- areolar connective tissue, elastic fiber.
Human Anatomy and Physiology I
Chapter 5 -- Review Questions
1. Describe the hypodermis. Is it part of the skin?
Yes, it’s part of the skin. The hypodermis is the innermost and thickest layer of the skin. It cushions the body and helps regulate skin and body temperature.
2. Describe the composition of the epidermis.
The epidermis is made up of Stratified Squamous Epithelium.
3. Name and discuss the four cell types found in the epidermis. (Give the structure and function of each) * Keratinocytes- 90% filled with keratin and have a waterproof barrier. * Melanocytes- 8% produce melanin pigment and pass them to the keratinocytes. * Langerhans cells- phagocytes from the immune system and are easily damaged by UV light * Merkle cells- located in deepest layer of hairless skin and they are the sensory transduction.
4. Name the five epidermal layers from the outside of the skin to the inside. Tell the structure of each. * Stratum Corneum- Most superficial layer; 20–30 layers of dead cells represented only by flat membranous sacs filled with keratin. Glycolipids in extracellular space. * Stratum Lucidum- Clear, translucent layer. Only found in palms and soles. * Stratum granulosum- Three to five layers of flattened cells, organelles deteriorating; cytoplasm full of lamellated granules (release lipids) and keratohyaline granules. * Stratum spinosum- Several layers of keratinocytes unified by desmosomes. Cells contain thick bundles of intermediate filaments made of pre-keratin. * Stratum basale- Deepest epidermal layer; one row of actively mitotic stem cells; some newly formed cells become part of the more superficial layers. See occasional melanocytes and epidermal dendritic cells.
5. Describe the composition of the dermis layer.
Dense irregular fibrous connective tissue.
6. Name and discuss the two layers of the dermis. * Papillary region- areolar connective tissue, elastic fiber.