Exploring Bacterial Structure and Function

Bacteria, one of the oldest organisms, are crucial to life on Earth. They can cause diseases but also play vital roles in human health, such as aiding digestion and protecting against pathogens. Bacteria are unicellular prokaryotes found in diverse environments. They lack a membrane-bound nucleus, with DNA located in the nucleoid. Bacterial cells have a flexible cell wall, flagella for movement, and pili for attachment and DNA exchange. They possess chromosomal and plasmid DNA, which carry genetic information and confer advantages like antibiotic resistance.

How old are bacteria estimated to be?

• 3.5 billion years

• 4.5 billion years

• 2.5 billion years

• 1.5 billion years

Which of the following diseases is NOT caused by bacteria?

• Tuberculosis

• Plague

• Cholera

• Diabetes

What is the ratio of bacterial cells to human cells in the human body?

• 10:1

• 20:1

• 5:1

• 1:1

Which of the following is NOT a benefit provided by good bacteria in the gut?

• Tumor prevention

• Vitamin production

• Pathogen fighting

• Causing infections

Where can bacteria be found?

• Only in soil

• Only in water

• Practically everywhere on Earth

• Only in the human body

What type of organisms are bacteria classified as?

• Unicellular prokaryotes

• Multicellular prokaryotes

• Unicellular eukaryotes

• Multicellular eukaryotes

Where is the DNA located in bacterial cells?

• In the nucleus

• In the nucleoid

• In the mitochondria

• In the ribosomes

What is the function of the bacterial flagellum?

• Protein synthesis

• DNA replication

• Attachment to surfaces

• Movement

What type of DNA carries most of the genetic information in bacteria?

• Mitochondrial DNA

• Plasmid DNA

• Ribosomal DNA

• Chromosomal DNA

What is the role of pili in bacteria?

• Movement

• Protein synthesis

• Energy production

• Attachment to hosts and surfaces