Epithelium Flashcards
From which embryological origins does epithelium arise?
A) Mesoderm
B) Ectoderm
C) Endoderm
D) All of the above
D) All of the above
Ectoderm gives rise to the epidermis, mesoderm gives rise to the inner lining of body cavities and the endoderm gives rise mucous membranes lining the digestive and respiratory tracts.
What are the 2 main functions of epithelia?
To line body surfaces and form secretory glands
What 2 layers make up the basement membrane?
1) Basal lamina
2) Reticular lamina
Label this image
A) apical surface
B) Lateral surfaces
C) Epithelium
D) Basal lamina
E) Reticular lamina
F) Basement membrane
G) connective tissue
Kidney tubules are lined by __?__ epithelium
Simple cuboidal
Alveoli are lined by __?__ epithelium
Simple squamous
The small intestine is lined by __?__ epithelium
Simple columnar
The oesophagus is lined by __?__ epithelium
Stratified squamous
Where would you find keratinised stratified squamous epithelium?
Only found in skin
An epithelial basement membrane consists of __1__ lamina and __2__ lamina
1) basal lamina 2) reticular lamina
The trachea is lined by __?__ epithelium
Pseudostratified columnar
Sweat gland ducts are lined by __?__ epithelium
Stratified cuboidal
(stratified as the cells beneath can store sweat)
Salivary gland ducts are lined by __?__ epithelium
Stratified columnar
Exocrine glands secrete into __?__
ducts that open into lumen of organ or onto the skin
Endocrine glands secrete into __?__
empty tissue spaces, eventually hormones enter the blood stream (no ducts)
What is the difference between merocrine, apocrine, and holocrine secretion?
- Merocrine: secretion passes from cells via exocytosis without damaging the cell or cell membrane. (think mediocre so the normal way u would think) e.g. saliva, sweat.
- Apocrine: Apical surface of cells pinched off to release pockets of the hormone. (think Apocrine = Apical) e.g. mammary glands.
- Holocrine: Whole-cell dies for secretion. (think of holocaust) e.g. sebum from sebaceous glands.
Epithelial membranes contain epithelium and __?__
An underlying connective tissue
Synovial membranes contain only __1__ tissues and line __2__
1) connective
2) joint cavities
Serous membranes are generally simple __1__ epithelium resting on a thin layer of __2__. The epithelium is also known as __3__(originating from mesoderm). The serosa is found lining __4__ or the 3 Ps __5__, __6__ and __7__. Produces ___5___ which gives lubrication.
1) Squamous
2) Loose connective tissue
3) Mesothelium (as it is formed from the mesoderm)
4) Closed internal body cavities
5) Pleura
6) Pericardium
7) Peritoneum
5) Serous fluid (that reduces friction between joints)
Cavities open to the external environment are generally lined by __1__ membranes. In the digestive tract, the mucosa has [microvilli/cilia], and in the respiratory tracts the mucosa has [microvilli/cilia].
1) mucous
2) microvilli
3) cilia
Serous membranes have two layers: the __1__ layer (attaches to the body wall around the organ) and the __2__ layer (attaches to the organ it surrounds).
1) parietal
2) visceral
The pleura (surrounding the __1__),
The__2__ (surrounding the heart)
The peritoneum (in the abdomen) are all prominent examples of __3__ membranes.
1) lungs
2) pericardium
3) serous
Between the two layers of the serous membrane is a fluid called __?__ fluid.
serous
Synovial membranes line the cavities of freely movable joints, and contain on __?__ tissues.
connective
Describe transitional cells and where they are found.
Layers which change their shape when stretched. Only found in the urinary tract.
How does the basal surface connect to underlying tissues?
Connect to it via the basement membrane derived from connective tissue.
Label this diagram
- A = Enterocytes
- B = Microvilli
- C = Villi
What are the roles of desmosomes? Where are they found and what proteins do they include?
The roles include holding epithelia together at their lateral surfaces. They are found as spots on the lateral surfaces and involve cadherin proteins.
What is the role of tight junctions?
Allows plasma membranes of neighbouring cells to fuse. This ensures nothing can get through except what the plasma membrane allows.
What is a glandular epithelium?
These are aggregates of epithelial cells that cluster together to perform certain secretory and excretory actions.
What type of membranes line:
- Digestive, respiratory, reproductive and urinary system
- Body cavities
- Skin
- Joints
- Mucous membranes
- Serous membranes
- Cutaneous membranes
- Synovial membranes
What type of membrane is this? Label it.
Mucous membrane
A) Mucus
B) Epithelium
C) Lamina propria (areolar connective tissue which is a type of loose connective tissue. Notice that under the skin, it is loose.)
Label this portion of a membrane.
This is the skin.
A) Epidermis
B) Dermis
What type of membrane is this? Label it.
Serous membrane
A) Transudate (serous fluid)
B) Mesothelium
C) Areolar tissue
What is this membrane? Label it.
Cutaneous.
A) Epithelium
B) Areolar connective tissue
C) Dense irregular connective tissue
What membrane is this? Label it
Synovial
A) Articular (hyaline cartilage)
B) Synovial fluid
C) Capsule
D) Capillary
E) Adipocytes
F) Areolar tissue
G) Epithelium
H) Synovial membrane
What is the difference between mesothelium and endothelium?
- The mesoderm originates from the mesoderm whilst the endothelium originates from ectoderm or endoderm.
- Mesothelium found within serous membranes and the endothelium is found lining inner surface of walls of vessels
