Questions and Answers
What is a prokaryote?
Prokaryotes do not have a nucleus or membrane-bound organelles.
What is a domain of prokaryotes that usually has a cell wall and reproduces by cell division?
Bacteria.
What is Archaea?
A domain of prokaryotes that are genetically very different from bacteria and have unique chemicals in their cell walls.
What are some characteristics of Archaea?
Signup and view all the answers
Where do Archaea often live?
Signup and view all the answers
What characterizes bacteria?
Signup and view all the answers
How do many bacteria obtain nutrients?
Signup and view all the answers
What is the structure of bacteria?
Signup and view all the answers
How do bacteria reproduce?
Signup and view all the answers
What is the first step in bacterial reproduction?
Signup and view all the answers
What happens after the DNA is copied in bacterial reproduction?
Signup and view all the answers
What is a virus?
Signup and view all the answers
Viruses are considered living organisms.
Signup and view all the answers
What significant event was caused by the 1918 flu virus?
Signup and view all the answers
How do viruses replicate?
Signup and view all the answers
What happens after new viruses are created?
Signup and view all the answers
Study Notes
Prokaryotes Overview
- Prokaryotes lack a nucleus and membrane-bound organelles.
- Two main domains of prokaryotes are Bacteria and Archaea.
Bacteria
- Bacteria possess cell walls and usually reproduce via cell division.
- They encompass the majority of known prokaryotic organisms.
- The bacterial domain contains more individuals than all other domains combined.
Characteristics of Bacteria
- Many bacteria function as consumers; they obtain nutrients by feeding on other organisms.
- Some bacteria are decomposers, feeding on dead organisms, while others are producers, using sunlight for energy.
- Bacteria are typically small, single-celled organisms, though they may form films or strands.
- Spiral-shaped bacteria can move in a corkscrew manner.
Reproduction in Bacteria
- Both archaea and bacteria reproduce through binary fission, where one cell splits into two.
- The process begins with copying the genetic material, which is structured as a long circular strand of DNA called a chromosome.
- After copying, the chromosomes separate to opposite sides of the cell before division.
Archaea
- Archaea are genetically distinct from bacteria and have unique cell wall chemicals.
- Many archaea thrive in extreme environments, such as hot springs or highly acidic habitats.
- Some archaea can utilize sulfur to generate energy near deep-sea vents.
Viruses
- Viruses are microscopic particles that cannot replicate independently.
- They must enter a host cell or inject their DNA to reproduce, often leading to cell destruction.
- Common viral illnesses include the common cold, flu, and AIDS.
Characteristics of Viruses
- Composed of genetic material and proteins, viruses do not perform metabolic functions.
- They can only replicate inside living cells, making them non-living entities.
Historical Impact of Viruses
- The 1918 influenza pandemic was caused by a deadly virus, resulting in over 50 million deaths and infecting more than 500 million people worldwide.
Viral Replication
- Viruses replicate exclusively within host cells, which provide essential resources for survival and proliferation.
- After replication, new viruses seek additional host cells, continuing the cycle of infection.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
This quiz focuses on key concepts related to prokaryotes, including bacteria, archaea, as well as an overview of viruses and other microorganisms. Each card defines important terms and differences, aiming to enhance understanding of microbial life forms. Perfect for students studying microbiology or related fields.