Week 1, Quiz 1

1. Thinking about how we classify living organisms into domains, which pair of organisms is most closely related?

Protozoa and algae

2. Which domains contain organisms that are always single-celled (unicellular)?

Archaea and bacteria

3. Ribosomal RNA (rRNA) is a good “evolutionary time clock” because…

All organisms have ribosomal RNA

It changes very slowly over time, organisms that are closely related have similar ribosomal RNA

DNA sequences of the ribosomal RNA genes can be compared between organisms

4. Which of the following can impact the balance of a person's microbiome?

overconsumption of antibiotics

how you were born

having a pet

whether or not you were fed formula or breast milk

5. Which kingdom category contains organisms that belong to 2 of the 3 domains (new system of classification)?

monera

6. Which of the following statements about Archaea are TRUE?

they look like bacteria under the microscope

they do not contain nuclei and organelles

7. Organisms A, B, and C all live in the same habitat where both glucose and lactose sugars are plentiful. Over a period of time, the glucose reserves disappear and only lactose remains as a food source.

A: can digest lactose and glucose equally well

B: preferentially digests glucose and is not as efficient at extracting energy from lactose, but can partially digest it

C: can digest glucose and fructose equally well but cannot digest lactose

Which statement expresses what is likely to be observed in this habitat two months after the glucose has disappeared?

The population is made up of mostly organism A and a smaller population of organism B

8. In examining this phylogenetic tree, which pair of organisms listed is MOST CLOSELY RELATED?

Fungi and Animals

Which of these may result from not having a diverse gut microbiome?

Asthma, allergies, obesity, autoimmune disorders

Viruses do NOT contain ribosomes. Based on this fact, which of the domains do you think viruses fall into?

They do not fall into a domain. They can’t be classified into any of the 3 domains since they don’t have ribosomal RNA