Species adaptations Flashcards
What is the role of the tubercles in fish
Accumulations of localised cornified cells
Have a role in species recognition, fighting defense etc
Define keratinisation
Process of differerentiation of living epidermal cells characteriesed by high cellular activity
Define cornification
Programmed death of living epidermal cells at the end of their differentiation. Dead epidermal cells become horn
Defien horn
FInal product or keratinisation and cornification build up by dead cells and intercellular material
What modifications can occur for hoof/horn?
- Basement membrane and dermis form elongated dermal papillae at coronary band
- Basal cells produce keratinocytes as usual which become squames
- Keratin squames glued together to form tubules
- Hoof slides over/between the dermal lamellae
- Takes 12-15 months for hoof to grow from coronary band to ground surface
How is horn. produce?
Wall before the coronary dermis
Wall at 5mm per month so there will be 15 months before the horn is weight bearing
Properties of the corium
- Highly vascular
- Dense connective tissue
- Papillae produce hollow horn tubules
- Grows like normal dermis/epidermis
- Start of lamellae next to the papillae
Growth of the solar corium
Horn grows down to the solar surface
What is the role of the dermis of the tooth?
Living tissue
Blood vessels
Nerves
Connective tissues
Blood and nerve supply
What is contained within the epidermis of the hoof?
Inner part living cells poroducing or supporting the horn
Outer part dead horn
Role is horn formation
What are the secondary lamellae of the hoof?
Special to equidae
Increase area of basement membrane
Increase strenth of the dermal epidermal bond
Hood gorwth = sliding between secondary lamellae
