What is a cell?
- A Cell is defined as the smallest, basic unit of life responsible for all life’s processes.
- Robert Hooke coined the term Cell in 1665.
- Cells provide structure and support to the body of an organism.
Types of Cell
- Prokaryotes
- The size of the cell is generally small
- Nucleus absent.
- It contains a single chromosome
- Membrane-bound cell organelles are absent.
- Cell division takes place by fission or budding.
- Eukaryotes
- The size of the cell is generally large.
- Nucleus present.
- It contains more than one chromosome
- Cell organelles are present.
- Cell division takes place by mitosis and meiosis
Parts of Cell
- Cell Membrane
- It maintains the integrity of a cell and controls the passage of materials into and out of the cell.
- All materials within a cell must have access to the cell membrane for the needed exchange.
- Nucleus & Nucleolus
- The nucleus determines how the cell will function, as well as the basic structure of that cell.
- Threads of chromatin in the nucleus contain Deoxyribonucleic Acid (DNA), the genetic material of the cell.
- The nucleolus is a dense region of ribonucleic acid (RNA) in the nucleus and is the site of ribosome formation.
- Cytoplasm
- Cytoplasm is a thick solution that fills each cell and is enclosed by the cell membrane.
- Within the cytoplasm lie intricate arrangements of fine fibers and hundreds or even thousands of minuscule but distinct structures called organelles.
Difference Between Plant And Animal Cell
- Plant Cell
- Cell are larger in size
- Cell wall – Present
- Plastid present
- Centrosome absent
- Vacuoles are larger in size
- Animal Cell
- Generally smaller
- Cell wall – Absent
- Plastid absent
- Centrosome present
- Vacuoles are smaller in size
