Classification and Characteristics of Organisms

The video tutorial discusses modern classification systems based on phylogeny, focusing on evolutionary history rather than physical similarities. It explains the use of cladograms to represent evolutionary relationships and the concept of derived characters. The role of molecular biology, including DNA and protein sequences, in classification is highlighted. The video also covers the three domains of life: Bacteria, Archaea, and Eukarya, detailing their unique characteristics and differences.

What is the primary basis for modern classification systems?

• Physical similarities

• Evolutionary descent

• Geographical location

• Behavioral traits

What is a cladogram used for?

• To list species alphabetically

• To depict evolutionary relationships

• To show physical similarities

• To measure genetic differences

What is a derived character?

• A trait that is unique to one species

• A trait that arose in the most recent common ancestor

• A trait found in all species

• A trait that is not inherited

What does a monophyletic group include?

• Only extinct species

• Species from different evolutionary branches

• A single common ancestor and all its descendants

• Species with similar physical traits

How has molecular biology impacted classification?

• It has only affected plant classification

• It has confirmed all traditional classifications

• It has had no impact

• It has led to reclassification of some species

Which domain includes organisms with peptidoglycan in their cell walls?

• Eukarya

• Archaea

• Bacteria

• Protists

What is a characteristic of Archaea?

• They have peptidoglycan in their cell walls

• They live in extreme environments

• They are photosynthetic

• They are all multicellular

Which group is known for being a 'catch-all' category in the Eukarya domain?

• Fungi

• Plants

• Protists

• Animals

What is a common feature of fungi?

• They are photosynthetic

• They are all decomposers

• They are all unicellular

• They have cell walls made of chitin

Which of the following is true about animals in the Eukarya domain?

• They never move

• They are heterotrophs

• They are all unicellular

• They are all photosynthetic