Epithelial Tissue And Exocrine Glands Flashcards
Where are mucous membranes found?(3)
Alimentary tract
Respiratory tract
Urinary tract
What do mucous membranes consist of? (3)
- Epithelium lining lumen of the tube
- Adjacent layer of CT (lamina propria)
- In alimentary tract, third layer consists of smooth muscle cells called muscularis mucosae
What is often present in the lamina propria?
Aggregations of lymphocytes (Peyer’s patches)
What is the difference between mucous and serous membranes?
Mucous membranes line cavities that open directly to the exterior whereas serous membranes line closed-body cavities (do not open to exterior)
True or false: serous membranes envelop the viscera
TRUE
What is viscera?
Internal organs in the main cavities of the body, especially those in the abdomen
What do serous membranes line that envelops the abdominal organs?
Peritoneum
What do serous membranes line that envelop the lungs?
Pleural sacs
What do serous membranes line that envelops the heart?
Pericardial sacs
Complete the sentence:
Serous membranes secrete ___________ _____ which promotes relatively friction-free movement of structures they surround.
Lubricating fluid
What do serous membranes consist of? (2)
- Simple squamous epithelium (mesothelium) which secretes a watery lubricating fluid
- Thin layer of CT which attaches epithelium to adjacent tissues (also carries blood vessels and nerves)
How do the heart, lungs and gut become surrounded by serous membrane during embryonic development?
They develop next to a bag-like cavity into which they invaginate (turned inside out or folded back on itself to form a cavity or pouch)
What is the name given to the serosa that forms the outer wall of the cavity?
Parietal serosa
What is the name of the serosa that covers the organ?
Visceral serosa
Name an exterior surface lined with epithelium
Skin
What is epithelium?
Sheets of contiguous (touching) cells, of varied embryonic origin, that cover external surfaces of the body and line internal surfaces
Name interior spaces which do not open to the exterior that are lined with epithelium
Pericardial sac Pleural sacs Peritoneum Blood vessels Lymphatic vessels
What is the basement membrane?
The name given to the thin, flexible, acellular layer which lies between epithelial cells and subtending CT
What does the basement membrane consist of?
Basal lamina which is laid down by epithelial cells and therefore lies closest to them
How can the thickness of the basement membrane be increased?
By a thick layer of reticular fibrils (type III collagen), elaborated by subtending CT
True or false: the basement membrane serves as a strong flexible layer to which epithelial cells adhere
TRUE
Where can simple squamous epithelium be found?(5)
- Lining of blood and lymph vessels (endothelium)
- Lining of body cavities - pericardium, pleura and peritoneum (mesothelium)
- Gas exchange epithelium (pulmonary alveoli)
- Bowman’s capsule (kidney)
- Loop of Henle (kidney)
What are the functions of simple squamous epithelium? (4)
- Lubrication (pericardium, pleura, peritoneum)
- Gas exchange (alveoli)
- Barrier (Bowman’s capsule)
- Active transport by pinocytosis (mesothelium and endothelium)