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Specialised Cells
Differentiation
DIFFERENTIATION is the process where a cell transforms into a SPECIALISED CELL for a specific job.
- It involves the development of DIFFERENT SUBCELLULAR STRUCTURES for various functions.
- In animal cells, most differentiation occurs at an early stage as the organism develops.
- In MATURE animals' cells, the ability to differentiate is mainly used for REPAIRING AND REPLACING cells, such as skin or blood cells.
- Plant cells NEVER lose their ability to differentiate.
- Undifferentiated cells are known as STEM CELLS.
Specialised Cells and Their Functions
Sperm Cells:
Specialised for REPRODUCTION
- Designed to deliver male DNA to female DNA.
- They have a LONG TAIL for mobility.
- They have MANY MITOCHONDRIA for energy.
- The head is STREAMLINED to make movement more efficient.
- The head contains ENZYMES that can digest through the membrane of the egg cell.
Nerve Cells:
Specialised for SENDING ELECTRICAL SIGNALS
- They carry messages in the form of electrical signals across the body.
- They are LONG to cover more distance.
- They have BRANCHED CONNECTIONS called DENDRITES to create a large network around the body.
Muscle Cells:
Specialised for CONTRACTION
- They are LONG, so they have space to contract.
- They are filled with MANY MITOCHONDRIA to transfer energy for contraction.
Root Hair Cells:
Specialised for ABSORBING WATER AND MINERALS.
- Grow long "hairs" to INCREASE SURFACE AREA for absorption from the soil.
- Contain NO CHLOROPLASTS as they are found underground and do NOT receive light for photosynthesis.
Phloem Cells:
Specialised for TRANSPORTING FOOD SUBSTANCES
- Cells are joined end to end to form TUBES to transport food in plants.
- They have very FEW SUBCELLULAR STRUCTURES to help substances flow through easily.
Xylem Cells:
Specialised for TRANSPORTING WATER AND MINERALS
- Cells are joined end to end to form TUBES to transport water and minerals in plants.
- They are HOLLOW for easy flow.
- They are made up of dead cells strengthened with LIGNIN.
Specialised Cells
Differentiation
DIFFERENTIATION is the process where a cell transforms into a SPECIALISED CELL for a specific job.
- It involves the development of DIFFERENT SUBCELLULAR STRUCTURES for various functions.
- In animal cells, most differentiation occurs at an early stage as the organism develops.
- In MATURE animals' cells, the ability to differentiate is mainly used for REPAIRING AND REPLACING cells, such as skin or blood cells.
- Plant cells NEVER lose their ability to differentiate.
- Undifferentiated cells are known as STEM CELLS.
Specialised Cells and Their Functions
Sperm Cells:
Specialised for REPRODUCTION
- Designed to deliver male DNA to female DNA.
- They have a LONG TAIL for mobility.
- They have MANY MITOCHONDRIA for energy.
- The head is STREAMLINED to make movement more efficient.
- The head contains ENZYMES that can digest through the membrane of the egg cell.
Nerve Cells:
Specialised for SENDING ELECTRICAL SIGNALS
- They carry messages in the form of electrical signals across the body.
- They are LONG to cover more distance.
- They have BRANCHED CONNECTIONS called DENDRITES to create a large network around the body.
Muscle Cells:
Specialised for CONTRACTION
- They are LONG, so they have space to contract.
- They are filled with MANY MITOCHONDRIA to transfer energy for contraction.
Root Hair Cells:
Specialised for ABSORBING WATER AND MINERALS.
- Grow long "hairs" to INCREASE SURFACE AREA for absorption from the soil.
- Contain NO CHLOROPLASTS as they are found underground and do NOT receive light for photosynthesis.
Phloem Cells:
Specialised for TRANSPORTING FOOD SUBSTANCES
- Cells are joined end to end to form TUBES to transport food in plants.
- They have very FEW SUBCELLULAR STRUCTURES to help substances flow through easily.
Xylem Cells:
Specialised for TRANSPORTING WATER AND MINERALS
- Cells are joined end to end to form TUBES to transport water and minerals in plants.
- They are HOLLOW for easy flow.
- They are made up of dead cells strengthened with LIGNIN.
