Cells: Discovery of Cells, Definition of Cells, Discovery of Stem Cells

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Definition of Cells

  • Cells can be defined as the basic structural and functional unit of life.

  • British Scientist Robert Hooke coined the term “cells” in 1665.

  • Under microscopic vision, honeycomb-like structures were observed, and these structures were called as cells.

  • Antonie Van Leuwenhoek was the first person to observe human cells and bacteria under his microscope.

  • With the invention of the electronic microscope, it became easier to observe objects smaller than the cells.

  • Robert Brown, a Scottish botanist discovered the first insights into the cell structure.

Definition of Cells

Definition of Cells

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A typical plant cell

A Typical Plant Cell

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A typical animal cell

A Typical Animal Cell

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Stem Cells

  • These special human cells can develop into many different cell types.

  • They can range from muscle cells to brain cells.

  • James Thomson and his subordinates isolated the embryonic stem cells from a human blastocyst.

  • The stem cells were discovered by Martin Evans and Matt Kauffman.

  • It is also believed by the researchers that the stem cells-based therapies may one day be used to treat serious illnesses such as paralysis and Alzheimer disease.

Characteristics of Cells

  • They are responsible for providing necessary structural support for an organism.

  • The cell organelles present in the cell are suspended in the cytoplasm.

  • The cell’s energy requirements are fulfilled by mitochondria.

  • The metabolic wastes and foreign particles in the cell are digested by the Lysosomes (A membrane-bound cell organelle).

Functions of the Cell

  • They provide necessary support and structure to the body.

  • They help in reproduction process.

  • Facilitation of growth occurs through mitosis.

  • The energy is provided and the transport of substances is allowed.

Cell Theory

  • All the living species are composed of cells.

  • A cell is the basic unit of life.

  • From pre-existing cells, all other cells arise.

FAQs

Q 1. What are the two types into which the cells can be classified primarily?

Answer:

Following are the two types into which cells can be classified primarily:

i) Prokaryotic cells

ii) Eukaryotic cells

Q 2. List two important functions of the cell.

Answer:

Two important functions of the cell are:

i) They provide necessary support and structure to the body.

ii) They help in reproduction process.

Q 3. Who discovered the Stem Cells?

Answer: The stem cells were discovered by Martin Evans and Matt Kauffman.

Q 4. Who was the first person to observe human cells and bacteria under his microscope?

Answer: Antonie Van Leuwenhoek was the first person to observe human cells and bacteria under his microscope.