Tissues 2 Flashcards
Describe the formation of exocrine glands.
A tube is formed as the cells are still attached to the basal lamina
Describe the formation of endocrine glands.
Cells lose contact with the surface and become a mass of specialised cells and accumulate around blood vessels
What types structures of exocrine gland are there?
Simple
Compound with many branches
What shape is a tubular gland?
Long, thin and relatively straight
What shape is an acinar gland?
Spherical, like a grape
What types of exocrine glands are there?
Mucous glands
Serous glands
Describe the secretions of mucous glands.
- Secretion rich in proteoglycans
- Secretion mixed with water gives mucus
Describe the secretions of the serous glands.
-Protein rich secretion
What are myoepithelial cells?
- Specialised epithelial cells which have contractile cytoplasm.
- They play and important role in encouraging secretion of substances into ducts
What is secreted during proteinaceous secretion?
Proteins or hormones
Describe steroid endocrine glands.
- They cannot store steroid hormones, only keep the precursor, however that can store protein hormones.
- Steroid hormones made on demand.
What are the parenchyma of liver epithelium?
Heptocytes
How are hepatocytes arranged in the liver?
-In rows between blood vessels which allows them to take part in secretion
What are the support epithelial cells in the liver involved in?
- Lining blood vessels
- Lining bile ducts
What are the parenchyma of kidney epithelium?
Epithelial cells
How are epithelial cells arranged in the kidney?
Organised into nephrons
What are the function of epithelial cells in the kidney?
Multiple functions:
- Filtration of blood
- Partial absorption of filtrate
- Overall to release urine from the kidney
What are the support epithelial cells of the kidney involved in?
- Lining blood vessels
- Lining renal pelvis
What classifies as abnormal function of epithelial cells?
-Over proliferation
-Under proliferation
-Over secretion
-Under secretion
Loss of cilia/ciliary beat
What does the pituitary gland secrete?
Growth hormone
What is the result of abnormal function of the pituitary gland/
Over production: Pituitary giantism
Under production: Pituitary dwarfism
How can disease affect the function of the uterine tube?
- It contains singles celled mucous glands.
- When infected with chlamydia trachomatis thick mucus is produced
- This can lead to infertility as ovum/sperm become trapped
What is considered connective tissue?
- Blood/bone marrow
- Cartilage
- Bone
- Adipose
What is connective tissue composed of?
- Fibres (solid rope like)
- Ground substance jelly like)
- Tissue fluid
What fibres are in connective tissue?
- Collagen
- Elastic
- Reticulin
What are the physical propertied of collagen?
- Inelastic but flexible
- Great tensile strength
What are 3 types of collagen?
- Type I in tendons
- Type III in reticulin
- Type IV in basal lamina (non-fibrous)
How is collagen formed?
- Fibroblasts produce procollagen which is acted on by collagenase
- Produces triple stranded helix
- Forms collagen fibril
- Forms collagen fibres
Where is reticulin found?
Lymph
What are elastic fibre made from?
Protein elastin
How far can elastic fibres stretch?
Can stretch to 1.5 times resting length
What are the components of elastic fibres?
- Microfibrils
- Amorphous component
How are elastic fibres usually found?
Generally found in sheets and yellow in colour
What does ground substance consist of?
- Proteoglycans (protein core+ GAGS)
- Hyaluronic acid
- Glycoproteins (laminin, fibronectin)
How can connective tissue be classified?
- Loose
- Dense regular
- Dense irregular
What is loose connective tissue made from?
Permanent fixed cells -Fibroblasts -Macrophages -Adipocytes -Mast cells -Undifferentiated mesenchyme cells Transient cells -WBC
What is an example of a dense regular tissue?
Tendon
What is an example of a dense irregular tissue?
Sebaceous gland in the skin
Give examples of abnormal functions of connective tissue.
- Blood/bone marrow: leukaemia
- Loose/dense: loss/abnormal fibres
- Cartilage: tear
- Bone: osteoporosis
