Cell The Unit of Life Test - 2

- The Kingdom Monera consists of all bacteria. Bacteria are single-celled organisms that are made of very simple components.

- Protozoans belong to the Kingdom Protista. Protozoa are single-celled eukaryotes.

- Nematodes and Arthropods are phylums of certain invertebrates and belong to the Kingdom Animalia.

- Bacteria are single-celled organisms.

- Bacteria are classified into 5 groups according to their basic shapes: spherical (cocci), rod (bacilli), spiral (spirilla), comma (vibrios) or corkscrew (spirochaetes). They can exist as single cells, in pairs, chains or clusters.

- There are three major known groups of Archae: methanogens, halophiles, and thermophiles.

- The methanogens are anaerobic bacteria that produce methane. They are found in sewage treatment plants, bogs, and the intestinal tracts of ruminants.

- Halophiles are bacteria that thrive in high salt concentrations such as those found in salt lakes or pools of sea water.

- Thermophiles are the heat-loving bacteria found near hydrothermal vents and hot springs.

- Archaebacteria emerged at least 3.5 billion years ago and live in environments that resemble conditions existing when the earth was young.

- Methanogens are present in the guts of several ruminant animals such as cows and buffaloes.

- They are responsible for the production of methane (biogas) from the dung of these animals.

- Methanogens are anaerobic bacteria that produce methane.

- Methanogens related to species of the genus Methanobrevibacter are the most highly represented archae in the gut of herbivores.

- Heterotrophic bacteria are the most abundant in nature.

- The majority are important decomposers.

- Many of them have a significant impact on human affairs.

- They are helpful in making curd from milk, production of antibiotics, fixing nitrogen in legume roots, etc.

- Some are pathogens causing damage to human beings, crops, farm animals and pets.

- Cholera, typhoid, tetanus, citrus canker are well known diseases caused by different bacteria.

Monerans do not have a nuclear membrane. Monera is a unicellular organism, they have a prokaryotic cellular organization, which means they lack a nuclear membrane and the DNA is naked.

The Mycoplasmas are organisms that completely lack a cell wall. They are the smallest living cells known and can survive without oxygen. Many mycoplasma are pathogenic in animals and plants.

All the given options, i.e. Streptococcus pneumonia, E. coli and Helicobacter pylori are bacteria and all bacteria belong to the Kingdom Monera. Therefore, D. All the above is the correct option.