functional cell
DESCRIPTION
Functional cell. Ajith Sominanda Department of Anatomy Faculty of Medicine University of Peradeniya. Multi cellular organism and the cell. CELL is the basic structural functional unit of life However, in multicellular organism, cells with specific function aggregate to form a tissue. - PowerPoint PPT PresentationTRANSCRIPT
Functional cell
Ajith SominandaDepartment of AnatomyFaculty of MedicineUniversity of Peradeniya
Multi cellular organism and the cell
CELL is the basic structural functional unit of life
However, in multicellular organism, cells with specific function aggregate to form a tissue.
Therefore the functional unit of multi cellular organism is TISSUE
Aim of this lecture
Function Structural adaptation/s of the cell
These cells are called parenchymal cells in the tissue or the organ
Functions of the cell
General functions1.Multiplication and growth2.Metabolism3.Cellular homeostasis4.Respond to the environmental stimuli
Specific functions1.epithelial cell2.Connective tissue cell3.Muscle cell4.Nerve cell
Multiplication and growth of the cell
• Depend on the stimulation (signal), cell starts to multiply and grow– These stimulations can be normal
physiological or pathological
Cell cycle
Normal Multiplication and growth of the cell
Pathological Multiplication and growth of the cell
‘Neoplasms’ ‘Tumors’ ‘’Cancers’’
MetabolismEndoplasmic reticulum (ER), Golgi apparatus & vescicles - The factory of life
the scavengers or recycling system Endo-lysosomal system
Cell membrane and cellular homeostasis
Specific cellular functions
• Cell structures change from its basic form (differentiate) to a specialized form to perform specific functions– Covering and lining– Secretion– Absorption– Support– Contractility and movement– Communication and response to stimuli
Covering and lining by epithelial cell
• Shape and form of the cell contributes to the function
• Cellular adhesions and basement membrane is critical for the integrity of the epithelium
Covering and lining by epithelial cell
• Presence of several cell layers to enhance the covering or lining function
Covering and lining by epithelial cell
• (Protein) synthetic machinery is fully functional • Nucleus is active• ER is active
Secretory cells
Glands (exocrine)
Glands (endocrine)
Cells with absorptive function
• Intestinal epithelial cells are adapted to increase the surface area
Cells adapted to supportive function
• Fibroblasts secretes fibers and maintain the cellular matrix
Contractility and movements
• Cilia are cell surface specializations that moves the substances on the cell surface
Contractility and movements
Contractility and movements
•Muscle fibers are arranged in longitudinal orientation•Fibers are arranged in bundles•Contractile elements are central and nuclei are peripheral
Communication and response
• Environment information transfer Information processing response
Receiver Processor
Effector
• Neuron has short and long processes
• Long processes are often covered with myelin to insulate the fiber to prevent short circuiting (effective nerve impulse transmission)
• Active nucleus and protein synthetic machinery for synthesis of neurotransmitters
Communication and response
Hepatocytes (liver), the interface between
GUT & the systemic circulation
Gut
MonosacharidesAmino acidsFatty acidsNucleic acidsMineralsVitaminsDrugsPoisons & chemicals
Portal vein
Hep
atic
ar
tery
Systemic bloodOxgenated blood
Hepatic
vein
Gallbladder & gut Systemic blood
Controlled release of materials
Bile
d
uct
80%20%
Basic cellular arrangement
Portal veinule
Central vein
Bile duct
sinusoid
Fenestrated, discontinuous endothelium
Space of Disse
Hepatic arteriole
Portal space
Liver is a factory
Raw materialsElectricity
Product output, Storage
Conclusion
Structural adaptations of the cell are for the function
Thank you