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Prokaryotic Cells

  • Prokaryotes are the most basic living organisms. These were the first cells that appeared on Earth.

Pro: Before

Karyotic: Nucleus

  • Animals and plants, along with other eukaryotes, have a nucleus where DNA is stored in the cell. Prokaryotes do not have a membrane-bound nucleus, but they do have a general area in the cell where the DNA resides.

  • There are two basic types of prokaryotes: Bacteria and Archaea.

  • Archaea are the more ancient group and, as a result, tend to live in extreme environments – salty lakes, the bottom of the ocean, and very hot environments.

  • Bacteria are found everywhere – in your body, on your skin, on practically every surface and place on Earth.

  • Prokaryotes can be both helpful and harmful to other living organisms.

Cell Theory

The Cell Theory applies to all living things and has three principles:

  1. Every living thing is made of cells.

  2. Cells come from existing cells.

  3. Cells are the basic unit of structure and function.

Structure

The function of a cell usually determines its structure.

  • All cells must have a cell membrane. Cell membranes surround the cell and serve as a barrier to the outside environment.

  • All cells must have genetic material (DNA).

  • All cells must have ribosomes. Ribosomes are used to produce proteins.

  • All cells have cytoplasm. Cytoplasm fills the free spaces in the cell, holding the parts of a cell in place.

Prokaryotic vs. Eukaryotic Cells

  • Eukaryotic cells have a nucleus, unlike prokaryotic cells.

  • Prokaryotes have a cell wall for protection, keeping shape, and preventing the cell from bursting. Some eukaryotes have cell walls, but not all.

Common Shapes of Prokaryotic Cells

  • Cocci

  • Bacilli

  • Spirilli

Edited: 05 October 2022

AV

Prokaryotic Cells

  • Prokaryotes are the most basic living organisms. These were the first cells that appeared on Earth.

Pro: Before

Karyotic: Nucleus

  • Animals and plants, along with other eukaryotes, have a nucleus where DNA is stored in the cell. Prokaryotes do not have a membrane-bound nucleus, but they do have a general area in the cell where the DNA resides.

  • There are two basic types of prokaryotes: Bacteria and Archaea.

  • Archaea are the more ancient group and, as a result, tend to live in extreme environments – salty lakes, the bottom of the ocean, and very hot environments.

  • Bacteria are found everywhere – in your body, on your skin, on practically every surface and place on Earth.

  • Prokaryotes can be both helpful and harmful to other living organisms.

Cell Theory

The Cell Theory applies to all living things and has three principles:

  1. Every living thing is made of cells.

  2. Cells come from existing cells.

  3. Cells are the basic unit of structure and function.

Structure

The function of a cell usually determines its structure.

  • All cells must have a cell membrane. Cell membranes surround the cell and serve as a barrier to the outside environment.

  • All cells must have genetic material (DNA).

  • All cells must have ribosomes. Ribosomes are used to produce proteins.

  • All cells have cytoplasm. Cytoplasm fills the free spaces in the cell, holding the parts of a cell in place.

Prokaryotic vs. Eukaryotic Cells

  • Eukaryotic cells have a nucleus, unlike prokaryotic cells.

  • Prokaryotes have a cell wall for protection, keeping shape, and preventing the cell from bursting. Some eukaryotes have cell walls, but not all.

Common Shapes of Prokaryotic Cells

  • Cocci

  • Bacilli

  • Spirilli

Edited: 05 October 2022

robot