Archaea Species Quiz: Hot Springs, Hydrothermal Vents, and Biomining

Prokaryotic Organisms

• Prokaryotic organisms, including archaebacteria and eubacteria, make up two of the three domains of life on Earth.
• They are single-celled organisms that lack a nucleus and organelles.

Archaebacteria

• Archaebacteria, also known as archaea, were recognized as a separate domain in the 1990s based on their unique genetic material.
• They are prokaryotic organisms that are more closely related to eukarya than eubacteria.
• Archaea can be found in extreme environments, such as hot springs, acidic mines, and frozen glaciers, as well as in more moderate environments.
• They have evolved to occupy niches with extreme conditions, similar to those on Earth 4-2.5 billion years ago.
• Archaea have been found in the gut of cows, and are not limited to extreme environments.

Characteristics of Archaebacteria

• Lack a nucleus and organelles.
• Have a unique cell structure, with a plasma membrane that can be a monolayer rather than a bilayer.
• Have a variety of cell walls, including a layer that protects and gives the cell its shape.
• Have pili, which allow cells to attach to surfaces and play a role in DNA transfer.
• Have flagella, which allow for movement.

Metabolisms of Archaebacteria

• Can be grouped by their means of obtaining energy, such as phototrophs, lithotrophs, and organotrophs.
• Can break down simple chemicals for energy, such as sulfur or ammonia.
• Can break down organic material for energy.

Habitats of Archaebacteria

• Can be found in extreme environments, such as high temperatures, acidic conditions, and high salinity.
• Can be found in environments with conditions not conducive to supporting life, such as hot springs and hydrothermal vents.
• Can also be found in more moderate environments, such as soils and the gut of humans.

Eubacteria

• Were previously grouped with archaea, but are now recognized as a separate domain.
• Are prokaryotic organisms that lack a nucleus and organelles.
• Are found in moderate environments, rather than extreme environments.

Characteristics of Eubacteria

• Lack a nucleus and organelles.
• Have a region within the cell called the nucleoid, where genetic material is stored.
• Have a single chromosome, with genes that code for similar proteins grouped together.
• Have a cell wall that gives the cell its shape and strength.
• Can have a capsule surrounding the cell wall, allowing for water retention and attachment to surfaces.

Metabolisms of Eubacteria

• Can be classified by their means of obtaining energy, such as chemoorganotrophs, chemolithotrophs, and photoautotrophs.
• Can feed on carbohydrates, inorganic molecules, and light.
• Can break down organic material for energy.

Habitats of Eubacteria

• Can be found in moderate environments, such as soils, water, and the human gut.
• Can be found in and on other organisms, and can be beneficial or harmful to those organisms.

Reproduction of Prokaryotic Organisms

• Both archaebacteria and eubacteria reproduce by a process of binary fission.
• The parent cell divides into two new daughter cells, each with the genetic information of the original parent cell.
• Genetic material can be transferred between cells through horizontal gene transfer.

Role of Prokaryotic Organisms in the Environment

• Archaea and eubacteria play a crucial role in nutrient cycling and are not limited to extreme environments.
• They can be found in abundance and are widespread among living organisms.
• They can assist with nutrient cycling, plant stress responses, and interactions between bacteria and the host organism.