Glands Flashcards
Define the term ‘gland’
Epithelial cell or collection of cells specialised for secretion
How are glands controlled? List some ways
- Nervous control
- Endocrine control
- Neuro-endocrine control
- Negative feedback
What is an exocrine gland?
gland with ducts that secretes onto a surface
What is an endocrine gland?
Ductless gland that secretes directly into the blood
What is a mucous gland?
Secretions contain mucus, rich in mucins (highly glycosylated polypeptides)
What is a serous gland?
Secretions are watery and free of mucus
What is endocytosis?
Opposite of merocrine secretion (engulfing material initially outside of cell). Transepithelial transport is endocytosis and exocytosis
Describe merocrine secretion
1) Membrane bound vesicle approaches cell surface
2) Vesicle fuses with plasma membrane
3) Contents of vesicle are in continuity with extracellular space
4) Plasma membrane becomes slightly larger
5) Membrane retrieved, stabilising cell surface
Describe apocrine secretion
1) Non-membrane bound structure approaches cell surface
2) Apical surface drapes around structure
3) Membrane surrounding droplet pinches off
4) Membrane added to regain original surface area
Describe holocrine secretion
Discharge of whole cell
What is the structure of serous membrane?
- Thin
- 2 part
Which cavities does serous membrane envelope?
- Viscera
- Peritoneum
- Pleural sac
- Pericardial sac
All closed, internal
Which cavities do mucous membranes line?
- Internal surfaces that open to exterior
- Alimentary
- Respiratory
- Urinary
What does the mucous membrane consist of?
- Mucus secreting cell
- Epithelium lining lumen of a tube
- Adjacent layer of connective tissue (lamina propria)
In the alimentary tract what other components of the mucous membrane are seen?
-Muscalaris mucosae (smooth layer of muscle cells)
