The cell is called the structural and functional unit of life because it is the smallest unit capable of carrying out all the functions necessary for life. Each cell is capable of metabolism, reproduction, responding to stimuli, and maintaining homeostasis.
- Metabolism: Cellular chemical processes for energy and growth.
- Reproduction: Creating new cells or offspring.
- Response to Stimuli: Reacting to environmental changes.
- Homeostasis: Maintaining internal stability.
Along with cell such as Smooth muscle cell, sperm & ovum, bone cell, nerve cell, fat cell, etc are special types of cell in human body have some special function to perform in the human body. There functioning and structure.
- Smooth Muscle Cell:
- Function: Involuntary contraction of hollow organs, blood vessels, and airways.
- Structure: Spindle-shaped with a single nucleus, lacking striations.
- Sperm & Ovum (Egg):
- Function:
- Sperm: Fertilization of the egg.
- Ovum: Reception of sperm and support of early embryo.
- Structure:
- Sperm: Small cell with head (nucleus), midpiece (mitochondria), and tail (flagellum).
- Ovum: Large cell with nucleus and nutrient-rich cytoplasm.
- Function:
- Bone Cell (Osteocyte):
- Function: Maintain bone tissue integrity and regulate mineral levels.
- Structure: Branched cell embedded in bone matrix, with processes extending into canaliculi.
- Nerve Cell (Neuron):
- Function: Transmit electrical impulses throughout the nervous system.
- Structure: Cell body (soma), dendrites (receive signals), axon (transmit signals), myelin sheath (speed up transmission).
- Fat Cell (Adipocyte):
- Function: Store and release energy, secrete hormones.
- Structure: Central vacuole filled with fat droplets, nucleus and organelles pushed to cell periphery.
