Bustan Science : Test1

Explanation
Prokaryotes are unicellular organisms that lack a nucleus and other membrane-bound organelles. They have a primitive nucleus, also known as a nucleoid, which contains the genetic material in the form of a single, circular DNA molecule. This is in contrast to eukaryotes, which have a true nucleus and other complex internal structures. Prokaryotes include bacteria and archaea, and they are known for their simplicity and ability to adapt to a wide range of environments.

Explanation
R.H. Whittaker proposed a 5 kingdom classification system. This system categorizes organisms into five distinct kingdoms: Monera, Protista, Fungi, Plantae, and Animalia. Each kingdom represents a different group of organisms based on their characteristics and evolutionary relationships. This classification system provides a more comprehensive and accurate way of organizing and studying the diversity of life on Earth compared to the previous 2, 3, and 4 kingdom classifications.

Explanation
The correct answer is "all of the above" because all the criteria mentioned - complexity of cell structure, complexity of organisms, mode of nutrition, life style, and phylogenetic relationship - are factors that can be used to classify organisms. These criteria help scientists categorize organisms into different groups based on their similarities and differences in these aspects.

Explanation
The correct answer is Kingdom Protista. Kingdom Protista is a diverse group of eukaryotic organisms that includes protozoa, algae, and slime molds. Many protists have various structures for locomotion, such as pseudopodia (temporary extensions of the cell membrane), hair-like cilia, and whip-like flagella. These structures enable protists to move and navigate through their environment.

Explanation
Lactobacilli belongs to the Kingdom Monera because they are a type of bacteria. The Kingdom Monera consists of single-celled organisms that lack a nucleus and other membrane-bound organelles. Lactobacilli are commonly found in the gastrointestinal tract of humans and animals and are known for their beneficial effects on digestion and immune function.

Explanation
Lactobacilli are not harmful bacteria. In fact, they are beneficial bacteria commonly found in the human body, particularly in the digestive system. They play a crucial role in maintaining a healthy gut by aiding in digestion, producing vitamins, and preventing the growth of harmful bacteria. Lactobacilli are also commonly used in probiotic supplements and fermented foods like yogurt. Therefore, the statement that Lactobacilli are harmful bacteria is false.

Explanation
The cell wall of fungi is made up of chitin. Chitin is a tough and flexible polysaccharide that provides structural support and protection to fungal cells. It is similar in composition to the exoskeleton of insects and the shells of crustaceans. Chitin is resistant to degradation by enzymes, making it an important component of the fungal cell wall, which helps the fungi withstand various environmental conditions.

Explanation
The correct answer is "all of the above" because algae are aquatic organisms, meaning they live in water. They are also chlorella, which is a type of green algae. Additionally, algae are autotrophic, meaning they can produce their own food through photosynthesis. Therefore, all three statements are true for algae.

Explanation
Viruses are considered to be at the edge of living and non-living organisms because they possess some characteristics of living organisms, such as the ability to replicate and evolve, but they lack essential features of living organisms, such as the ability to carry out metabolic processes on their own. Viruses can only replicate inside host cells by hijacking their cellular machinery. They are essentially genetic material (DNA or RNA) enclosed in a protein coat and are unable to carry out any life processes outside of a host cell. Therefore, viruses are often described as "obligate intracellular parasites" and are considered to be on the border between living and non-living entities.