A Level Biology - Biodiversity Quiz

Which of the following is a characteristic of all three domains (Bacteria, Archaea, and Eukarya)?

• Presence of membrane-bound organelles

• Circular DNA

• Ribosomes for protein synthesis

• Cell wall made of peptidoglycan

Answer explanation

All three domains—Bacteria, Archaea, and Eukarya—share the presence of ribosomes for protein synthesis, which are essential for translating mRNA into proteins. The other options are not universally applicable to all three domains.

Archaea differ from Bacteria in that they:

• Lack ribosomes

• Have histones associated with DNA

• Have mitochondria

• Undergo mitosis for cell division

Answer explanation

Archaea have histones associated with their DNA, which is a key difference from Bacteria that typically do not. This structural feature is important for DNA packaging and regulation.

Eukaryotes are distinguished from prokaryotes by the presence of:

• 70S ribosomes

• Circular chromosomes

• Membrane-bound organelles

• Peptidoglycan cell walls

Answer explanation

Eukaryotes are characterized by the presence of membrane-bound organelles, such as the nucleus and mitochondria, which are absent in prokaryotes. This distinction is crucial for cellular organization and function.

Which domain includes unicellular organisms that often live in extreme environments?

• Archaea

• Bacteria

• Eukarya

• Protozoa

Answer explanation

The domain Archaea includes unicellular organisms that thrive in extreme environments, such as hot springs and salt lakes. Unlike Bacteria, Archaea have unique biochemical properties that enable them to survive harsh conditions.

Which characteristic is unique to Bacteria and not found in Archaea or Eukarya?

• DNA wrapped around histones

• Cell wall containing peptidoglycan

• 80S ribosomes

• Linear DNA

Answer explanation

The characteristic unique to Bacteria is the cell wall containing peptidoglycan. Archaea have different cell wall compositions, and Eukarya do not have peptidoglycan in their cell walls.

Which kingdom contains only multicellular, heterotrophic organisms?

• Monera

• Protista

• Fungi

• Animalia

Answer explanation

The kingdom Animalia consists exclusively of multicellular, heterotrophic organisms, meaning they obtain food by consuming other organisms. In contrast, Monera and Protista include unicellular organisms, while Fungi are primarily decomposers.

The key characteristic of fungi that distinguishes them from plants is:

• Their ability to photosynthesize

• Cell walls made of chitin

• Presence of chloroplasts

• Multicellular organization

Answer explanation

Fungi are distinct from plants primarily due to their cell walls, which are made of chitin, unlike the cellulose found in plant cell walls. This key difference is crucial in classifying these organisms.

Which kingdom consists of prokaryotic organisms?

• Animalia

• Fungi

• Monera

• Protista

Answer explanation

The kingdom Monera consists of prokaryotic organisms, which are unicellular and lack a nucleus. In contrast, Animalia, Fungi, and Protista are composed of eukaryotic organisms.

Which of the following features is found in all plants?

• Autotrophic nutrition

• Ability to move actively

• Lack of cell walls

• Heterotrophic feeding

Answer explanation

All plants exhibit autotrophic nutrition, meaning they produce their own food through photosynthesis. The other options, such as ability to move actively, lack of cell walls, and heterotrophic feeding, do not apply to all plants.

A unicellular eukaryotic organism that moves using cilia and feeds on bacteria most likely belongs to which kingdom?

• Protista

• Plantae

• Animalia

• Fungi

Answer explanation

The organism is unicellular and eukaryotic, which fits the Protista kingdom. Its movement using cilia and feeding on bacteria further confirms its classification in Protista, as these characteristics are typical of protozoans.