Cell

• What is cell?

  A cell is the basic structural and functional unit of living organisms. It is the smallest unit of life that can replicate independently, and its often referred to as the building block of life.
• Cells can vary in size, shape, and function, but they all contain genetic material (DNA or RNA) and carry out essential processes necessary for life, such as metabolism, growth, and reproduction.
• Red Blood Cells

  Responsible for carrying oxygen from the lungs to the rest of the body and transporting carbon dioxide to the lungs
• White Blood Cells

  Part of the immune system, they help defend the body against infections and foreign invaders.
• Neurons

  Nerve cells that transmit signals throughout the body, allowing us to think, feel and move.
• Muscle Cells

  Responsible for generating force and movement, allowing us to perform various types of physical activities.
• Skin Cells

  Form the outer protective layer of the body and help regulate temperature and sensation.
• Bone Cells

  Including osteoclasts, which are involved in bone formation, maintenance, and remodeling.
• Liver Cells


  Responsible for detoxifying chemicals, metabolizing drugs, and producing bile, which aids in digestion.
• Pancreatic cell

  Produce hormones like insulin and glucagon, which regulate blood sugar levels, as well as digestive enzymes that aid in digestion.
• Discovery of cell

  The discovery of cell was credited to the work of Robert Hooke in 1665, using a primitive microscope, he observed small compartments in cork and named them "cells"
• The cell theory

  1. All living things are made up of cells
  2. The cell is structural and functional unit of all living things
  3. All cells come from pre-existing cells.
• Spontaneous Generation

  Before the cell theory people believed in spontaneous generation which means living things come from non-living things.
• Two Scientist Disproved spontaneous generation

  • Francesco Redi
  • Louis Pasteur
• Theodor Schwann

  Was a German physiologist who played crucial role in the development of cell theory. In 1839, Schwann proposed that all animal are composed of cells.
• Matthias Schleiden (Plant Cells)

  Was German botanist who is also known for his contributions to cell theory. He proposed that all plants are composed of cells, based on his observations of plant tissues under the microscope.
• Rudolf Virchow 


  Significant contribution to the third principle of cell theory was based on his observations and conclusion regarding the origin of cells. Proposed that idea that "every cell comes from pre-existing cells.
• Zacharias Janssen

  Invented the first compound miscroscope
• Robert Hooke

  In 1663 an English scientist, Robert Hooke improved Janssen's invention.
• Anton Van Leeuwenhoek


  Ten years later Anton van Leeuwenhoek used his own single lens microscopes and was the first person to observed bacteria and protozoa.
• Leeuwenhoek's Microscope

  Resemble high power magnifying lenses
• Carl Zeiss

  Was a German optician and business man who co-founded the optics company Carl Zeiss AG. Together with Ernst Abbe and Otto Schott, Carl Zeiss played a crucial role in advancing the field of optics and microscopy.