Histology Unit 1 Integument

What is the largest organ of the body?

Skin/integument

Skin consists of what three layers?

Epidermis, Dermis, and Hypodermis

What layer of skin is not technically part of skin?

Hypodermis

What does skin protect us from?

The sensory function of skin allows for what?

The secretion/excretion allows for what substances to be secreted/excreted?

The regulation of body temperature typically leads to what?

The absorption of ultraviolet leads to what?

Dehydration and infection. Feeling temperature. Sweat and oil. Sweating or shivering. Vitamin D production

What type of epithelium can be found in the Epidermis of skin?

Is the epidermis avascular or vascular?

Keratinized stratified squamous. Avascular

In the Dermis, what does it have a high supply of?

Is there a high or low number of cells?

What type of collagen is found here?

What type of connective tissue is found here?

Blood. Low. Type 1 collagen. Dense irregular connective tissue

In the Hypodermis, what type of connective tissue is found?

Loose connective tissue

What is labeled as 5?

Labeled as 1 & 2?

Labeled as 3?

Epidermis. Dermis. Hypodermis

What are the two different classifications of Epidermis?

Thick and Thin skin

The epidermis has two different classifications. What are they?

Which of these do animals typically have a low distribution of?

Thick and thin skin. Thick skin

Another name for thick skin?

For thin?

Glabrous. Nonglabrous

In thick skin, are hair follicles present?

How many identifiable epidermal layers?

What type of sweat glands are present?

No. 5 identifiable layers. Merocrine sweat glands

In thin skin, are hair follicles present?

What epidermal layer is absent in thin skin?

What type of sweat glands are present?

Yes. Stratum lucidum. Apocrine sweat glands

What are the 5 layers of thick skin?

Stratum basale, Stratum Spinosum, Stratum Granulosum, Stratum Lucidum, Stratum Corneum

What layer is in dark blue?

What layer is in purple?

What layer is in pink?

What layer is in light purple?

What layer is in light blue?

Stratum basale, Stratum Spinosum, Stratum Granulosum, Stratum Lucidum, Stratum Corneum

What layer of skin has cell division where stem cells give rise to keratinocytes and has melanocytes and Merkel cells?

What does this layer sit on?

Stratum Basale. Basement membrane

What layer of skin has cells that are connected by Desmosomes and have spines to connect them? It also has coated granules covered in lipids to keep water out of and within the membrane. Keratinization also begins here.

Stratum Spinosum

What is the last layer in skin that still has nuclei and also has Keratohyalin granules?

Why do these cells still have a nuclei?

Stratum Granulosum. They are farther away from the basement membrane, so it is harder to get its needs met

What layer of skin is only in thick skin, lacks organelles and nuclei, and keratin filaments?

Stratum Lucidum

What layer of skin has Desmosomes further from the surface that need to be maintained but as they get closer to surface Desmosomes breakdown and slough off and becomes desquamated (dead skin cells)?

Stratum Corneum

What are the three cells found in the Epidermis?

Melanocytes, Dendritic cells, and Merkel cells

Within Epidermis there are what type of cells found in the Stratum basale that are a source of melanin for keratinocytes?

Melanocytes

The Melanocytes in epidermis are located in what layer?

Melanocytes are packaged as “packets” called what?

Basal layer. Melanosomes

What are the small granules that the Melanosome pinches off that shield the nucleus and other stem cells in the stratum basale from UV?

Melanin granules

What type of cell is circled in pink?

What layer of Epidermis is circled in light purple (see spiky-like connections)?

What is circled in red?

Melanocytes. Stratum Spinosum. Melanin granules

What cells found in Epidermis are light-touch receptors that are slow-adapting, located in the basal region, and take a special stain to visualize?

Merkel cells

What cell in Epidermis has Langerhans cells?

These Langerhans cells are derived from what?

Dendritic cells. Monocytes

Dendritic cells also have these types of cells that phagocitize foreign bacteria and patrols the Epidermis?

Antigen presenting cells

The dermis what what two layers?

Reticular and Papillary

The Reticular layer can be found in what type of skin (thick or thin)?

The papillary layer can be found in what type of skin?

Thick and thin. Thick only

In the Reticular layer what type of connective tissue is present?

What type of collagen is present?

What type of glands are present?

Are hair follicles present?

What type of receptors are present?

Dense irregular connective tissue. Type 1. Sweat glands. Yes. Mechanoreceptors

In the Papillary layer, there are ___ into the epidermis.

What type of connective tissue is present?

What type of fibrils are present from basal lamina of the epidermis?

Projections. Loose connective tissue. Anchoring fibrils

The Hypodermis is made of what type of connective tissue?

It anchors the dermis to underlying what?

It is primarily made up of what tissue (also on pads on the bottom of feet)?

Loose connective tissue. Muscle or bone. Adipose tissue

What type of burn classification only affects the Epidermis?

Once the Epidermis is gone, what is the body battling?

1st degree burn. Dehydration and infection

What type of burn classification entered the dermis?

2nd degree burn

What type of burn classification entered the Hypodermis?

3rd degree burn

What type of burn classification reaches the muscle?

4th degree burn

Sebaceous glands have what method of secretion to release sebum?

The sebum have what two properties?

Holocrine secretion. Antimicrobial and waterproofing.