Lab 3 - Histology Flashcards
Groups of similar cells that work together to carry out a specific function are called?
Tissues
To perform specific body functions, various tissues are organized into?
Organs
Name the four major tissue types
- Epithelial 2. Muscular 3. Connective 4. Nervous
What is histology?
The microscopic study of tissue structure and function
What do epithelial tissues cover?
The cover external body surfaces, line cavities and hollow organs and they form glands
What is epithelial tissues function?
Protection, absorption, secretion, filtration, and excretion
Name some distinguishing characteristics of epithelial tissue (4)
- They do not have blood supply 2. The tissue always attached to a basement membrane (basal surface) and always has a free surface (apical surface) 3. The cells can regenerate by mitosis 4. They may produce secretions
If epithelial cells do not have a blood supply, how do they get their nutrients?
Via the underlying connective tissue
Name the three classes of epithelial tissue.
- Simple epithelium 2. Stratified epithelium 3. Pseudostratified epithelium
Name three other classes of epithelial tissue based on shape
- Squamous 2. Cuboidal 3. Columnar
How is nervous tissue involved in maintaining homeostasis?
Nervous tissue helps to control and regulate other parts of the body by sending signals when the body deviates from the norm.
What is the integumentary system?
Consists of the skin and its accessory structures like glands, hair, muscles and nerves.
What is the function of the integumentary system?
- Protects against mechanical stress 2. Regulates water and heat loss 3. Acts as the site of Vitamin D synthesis
Name the two distinct regions of the integumentary system?
Superficial epidermis And deeper dermis
What is the epithelium composed of?
Composed of stratified squamous epithelium
What is the dermis composed of?
Composed of a layer of connective tissue
What lay below the dermis?
Hypodermics and subcutaneous layer
What is the epidermis made of?
Keratinized stratified squamous epithelium
How many skin layers are present in thick-skinned areas such as the palmar and plantar regions?
Five layers
What are the five layers of skin?
- Stratum corneum 2. Stratum lucidum 3. Stratum granulosum 4. Stratum spinous 5. Stratum basale
In thin-skinned areas which layer is not present?
Stratum lucidum
What are the dermal papillae? What is their function?
Are finger like projections that attach to dermis to the epidermis. Numerous collagen and elastic fibers attach to the dermis to the subcutaneous layer.
True or false: The dermis is highly vascularized.
True
What are stimulated by environmental changes and transmit messages to the brain for interpretation.
Cutaneous sensory receptors
What attaches the dermis to the underlying structures.
Hypodermis
Where can the accessory structures such as finger nails, sweat glands, and hair be found in the skin?
They are derived from the stratum basale.
What is the stratum corneum?
Outermost layer of epidermis that undergoes exfoliation.
What is the stratum lucidum?
Thick skin on finger tips, 3-5 layers of flat dead cells found on the palms of hands and the soles of feet
What is the stratum granulosum?
8-10 cell layers thick that are tightly packed together.
What is the stratum basale?
The very bottom layer of the epidermis that connects to the basement membrane. They are cuboidal columnar cells
What is the dermal papillae?
They attach the dermis to the epidermis, is also brings nutrients and oxygen to the lower layers of the epidermal cells
What is the corpuscle of touch?
This can be found in the dermal papillae of hairless skin and is used to sense pressure.
What is the lamellated/pacinian corpuscle?
In the the subcutaneous layer of the dermis it is the nerve endings in the skin responsible for sensitivity to vibrations and light touch
What is the subcutaneous layer?
This is the inner most layer of skin that act as an insulator and regulates body temperature
What is the function of the hair follicle?
To produce hair
What is the function of hair?
Regulate body temperature
What is the arrector pili muscle?
A muscle that surrounds the hair follicle and pulls the hair upright, makes goosebumps.
What is the sebaceous gland?
Can be seen connected to the hair follicle, secretes oily or waxy sebum on the lumen to lubricate and water proof the skin
What are the sudoriferous glands?
Sweat glands
Where the eccrine glands be found?
Everywhere
Where can the apocrine glands be found?
Only in the axillary and genital area.
What is the function of the eccrine gland?
Secrete on to lumen where it cools the skin by evaporation as a way to regulate body temperature
What is the function of the apocrine gland?
Releases fatty secretions to lumen where local bacteria break it down to an odorous fatty acid.
Give two functions of keratinocytes.
- Form a barrier against environmental damage by sensing when foreign body comes in contact with epidermis and signals leukocytes to attack the site.
What is the function of the capillary networks in the dermis?
To supply the dermis with nutrients and oxygen needed
What regions of the body do not have hair?
Palms of hands and soles of feet - ie places with thick skin or stratum lucidum
Which layer of the epidermis have accumulations of melanin in their cells?
Stratum spinosum
What is the function of melanin in the skin?
Protect against UV rays and also influence skin colour
What is the origin of carotene?
Can be found in the stratum corneum and the dermis
What is the function of carotene?
Can be converted to vitamin A
What is the function of keratinized skin?
Designed to shed often to protect from external contagions.
What is the functions of non-keratinized skin?
Designed for protection and lubrication during things such as swallowing and chewing
Name the tissue
Describe simple squamous epithelium
What is the locations of simple squamous epithelium
What is the function of simple squamous epithelium?
Name the tissue
Describe simple cuboidal epithelium
Where can simple cuboidal epithelium be found?
What is the function of simple cuboidal epithelium?
Name the tissue
simple columnar epithelium
Describe simple columnar epithelium
Where can simple columnar epithelium be found?
What is the function of simple columnar epithelium?
Name the tissue and what additional you can see in this photo
Describe pseudostratified ciliated columnar epithelium
Where can you find pseudostratified ciliated columnar epithelium?
What is the function of pseudostratified ciliated columnar epithelium?
Name the tissue
Stratified squamous epithelium
Describe stratified squamous epithelium
several layers of cells, you will see squamous at the apical surface and cuboidal or columnar at the basal surface
Where can stratified squamous epithelium be found?
What is the function of stratified squamous epithelium?
Name the tissue
Describe transitional epithelium
What is the location of transitional epithelium?
What is the function of transitional epithelium?
What is an endocrine gland?
What is an exocrine gland?
Endocrine glands such as ________ and ________ secrete ________.
Name an example of an exorcine gland
What is the unicellular exocrine gland and what does it produce?
Name the tissue
Describe the pancreas tissue
Where can pancreas tissue be found?
What is the function of pancreas tissue?
Name the tissue
Describe the salivary gland
What is the locations of the salivary glands?
What is the function of the salivary glands?
Name the tissue
Describe the sebaceous gland
What is the location of the sebaceous gland?
runs along the hair follicle
What is the function of the sebaceous gland?
Name the gland
Sudoriferous gland
Describe the sudoriferous gland
What is the locations of the sudoriferous glands?
What is the function of the sudoriferous glands?
Name the tissue.
Describe areolar connective tissue.
Where can areolar tissue be found?
What is the function of areolar connective tissue?
What is the most common functions of connective tissue?
- Protect
- Support
- Bind together other tissues
- Insulate
- Transport
- Act to store energy as fat
Name the two major components of the extracellular matrix.
What is the function of the three different types of fibers?
What are the kinds of ground substance that may be seen?
Name the three types of fibers.
How can you distinguish collagen fibers and what is their function?
Where can collagen fibers be found?
How can you distinguish elastic fibers and what is their function?
Where can elastic fibers be found?
How can you distinguish reticular fibers and what is their function?
Where can reticular fibers be found?
Form the framework for many soft organs like the spleen and lymph nodes and form part of the basement membrane of epithelial tissue.
Name the tissue
Describe adipose connective tissue.
the nucleus and cytoplasm are displaced peripherally due to a large internal fat droplet. The matrix is sparse and the cells are closely packed.
Where can adipose connective tissue be found?
What is the function of adipose connective tissue?
Name the tissue
Reticular connective tissue
Describe reticular connective tissue.
Where can the reticular connective tissue be found?
What is the function of reticular connective tissue?
ties cells of smooth muscle together filter blood into spleen, remove bacteria from lymph nodes.
Name the tissue
dense irregular connective tissue
Describe dense irregular connective tissue.
They appear as wavy bundles of parallel collagen fibers. The whole cell is darkly stained, and is seen between bundles of light pink fibers
Where in the body would you find dense irregular connective tissue?
What is the function of dense irregular connective tissue?
Name the tissue.
Describe hyaline cartilage
Where in the body would you find hyaline cartilage?
On the ends
What is the function of hyaline cartilage?
to reduce friction
Name the tissue
Describe bone tissue
What is the function of bone?
Name the tissue
Describe blood smear
What is the function of blood?
provide clotting, immune function, and carries nutrients and O2 while getting rid of waste products and CO2
Name the three types of muscle tissue.
What is the function of muscle tissue?
Name the tissue
Describe how you can distinguish skeletal muscle tissue.
Where can skeletal muscles be found?
Name the muscle tissue
What is the function of skeletal muscle fibers?
they are voluntary and conscious muscle contractions that assist in the movement of the body
How can you distinguish cardiac muscle tissue?
What is the function of the cardiac muscles?
Name the muscle tissue.
How can you distinguish smooth muscle tissue?
they are short, spindle shaped cells with a single central nucleus. The contraction is considered involuntary
Where can smooth muscle tissue be found in the body?
in the walls of hollow organs such as blood vessels, gi tract, and the bladder
What is the function of smooth muscle tissue?
What is the function of intercalated discs?
They support synchronized contraction of the cardiac muscles, allows the cardiac muscles to work as a single functional unti
What can be seen in this photo?
How can you distinguish a neutron?
they have a large cell body with multiple extensions
Where can neurons be found?
How can neuroglia be distinguished?
Where are the neuroglia located?
What are the functions of the neuroglia?
Functions in supporting the neurons.
What is the basic function of the nervous tissue?
to process stimuli
