Specialized cells

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Specialized cells
In a large multicellular organism there are lots of different types of cells. Each cell performs its specific role. So the different cells are arranged together carrying their unique role. This has been achieved by specialization of the cells. Some specialized cells are given below.
Cheek cells
Structure

Function line the inside of the mouth Location inside of mouth Adaptation thin, flat, irregular margin so that they can fit together closely
Muscle cells
Function Contract and relax to bring about movements Location Attached to the skeleton Adaptation Made up of contractile proteins, actin and myosin

Ovum

Function

to develop into a baby after they are fertilized

Location

produced in the ovary

Adaptation

a large food storage in the cytoplasm. Jelly like layer surrounds cell membrane that prevents entry of more than one sperms. Nucleus contains 23 chromosomes so that after fertilization 46 number of chromosomes may be restored.

Cells and tissues - ZAFARS BIOLOGY NOTES

Sperm cell

Function

to fertilize an ovum.

Location

produced in the testis.
Adaptation

Neuron or nerve cell

Function

transmit electrical signals from sensory receptors and to effectors.
Location
brain spinal cord, and nerves.
Adaptation
The cells have a long fiber that extends from receptors to coordinator and from coordinator to the effectors so they transmit impulses from one to the other place. The long fiber is covered with fatty sheeth that provides insulation and restore potential difference inside and outside of the membrane of the neuron cell and speeds up nerve impulses. The nodes of ranvier further speed up the rate of impulse transmission by establishing mini circuits. Each neuron has many branched endings to make connections with other cells.

Ciliated cell

Function
Helps transport of materials
Location
Line the inside of the wind pipe.
Line the inside of the fallopian tubes.

Adaptation

Have tiny hair like cilia projecting from the surface. The cilia beat by moving to and fro very quickly and bring about the transport of the materials. In wind pipe propel the dust and pathogens trapped in mucus upward so that they may be swallowed or coughed out. In the fallopian tube they bring about the movement of eggs down from the ovary to the uterus.

Erythrocyte

Function
Transport oxygen
Location Blood vessels

Adaptation

The cytoplasm is filled with the pigment haemoglobin, which combine with oxygen reversibly to make oxyhaemoglobin and transports it from lungs to the tissues. The cells have no neucleus that provide more room for the presence of haemoglobin. Being flat and enucleate they can be forced through the narrowest blood capillaries. They do not posses nucleus so they don’t divide and do not use oxygen for their metabolic activities. Lymphocyte

Function
Produce antibodies that protect against pathogens.
Location Blood stream.

AdaptationThey have large nucleus that contains many copies of genes to make a large variety of antibodies, which are specific to their antigens.
Phagocyte

Function
Location

click to see a phagocyte in action

Adaptation

Xylem vessels

Function Transport water and supports the plants
Location Vascular bundle in plants.

Adaptation

The cells do not have cytoplasm, so do not provide hinderance to the f;low of water. They are attached end to end and do not have end plates so they make a capillary tube like structure that helps the water rise in them. The walls are deposited an additiona substance called lignin that provides extra strength and provides support.

Root hairs

Function Absorb water and minerals
Location Roots of plants.

Adaptation The cells have long extensions which increase the surface area for absorption of materials. They are live cells that provide energy for the active uptake of materials.
Mesophyll cells

Function photosynthesis
Location Leaves of plants

Adaptation
They contain chloroplast


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ZAFFAR	Latest page update: made by ZAFFAR , Nov 9 2007, 2:39 AM EST (about this update About This Update Edited by ZAFFAR view changes - complete history)
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