Questions and Answers
Which characteristic of living organisms involves the regulation of internal chemical balance?
What is the significance of Pelagibacter ubique in the ocean ecosystem?
Which of the following options represents an example of an organism that is likely very old and has a vast underground network?
Which organism is known for its extensive spread, spanning approximately 180 km²?
Signup and view all the answers
How do living organisms primarily generate variation according to the content?
Signup and view all the answers
What does the unity of organization refer to in the context of living organisms?
Signup and view all the answers
What is the primary characteristic that allows organisms to make copies that resemble them?
Signup and view all the answers
Which factor does NOT contribute to the diversity of life on Earth as mentioned?
Signup and view all the answers
What characteristics did LUCA possess?
Signup and view all the answers
When did LUCA likely exist?
Signup and view all the answers
What type of environments can prokaryotes survive in?
Signup and view all the answers
What is the primary genetic material found in all living organisms?
Signup and view all the answers
What is the genome size of LUCA estimated to be?
Signup and view all the answers
Which of the following best describes prokaryotic diversity?
Signup and view all the answers
What functions as the energy currency in all living cells?
Signup and view all the answers
What process allows living organisms to transcribe genetic information into functional products?
Signup and view all the answers
Where is it theorized that life on Earth may have originated?
Signup and view all the answers
Which of these statements about the genetic code is true?
Signup and view all the answers
What role can RNA molecules play in biological processes?
Signup and view all the answers
How old is the Earth approximately?
Signup and view all the answers
What do we call the earliest signs of life on Earth, based on fossil evidence?
Signup and view all the answers
What energy source do prokaryotes use for their metabolism?
Signup and view all the answers
Which of the following prokaryotes specializes in chemoautotrophy?
Signup and view all the answers
Which component do cyanobacteria use to convert sunlight into chemical energy?
Signup and view all the answers
What significant role did cyanobacteria play in Earth's history?
Signup and view all the answers
Besides cyanobacteria, which group is mentioned as an example of a photoautotroph?
Signup and view all the answers
What was primarily responsible for most of the carbon fixation throughout Earth's history?
Signup and view all the answers
What process allows the conversion of inorganic carbon (CO2) to organic forms?
Signup and view all the answers
Which of the following statements about cyanobacteria is false?
Signup and view all the answers
Which type of archaea prefers highly acidic environments with a pH of 2-3?
Signup and view all the answers
What is the role of prokaryotes in the nitrogen cycle?
Signup and view all the answers
Which archaea are known to live in extremely cold environments, such as Antarctic sea ice?
Signup and view all the answers
What is bioremediation?
Signup and view all the answers
Which of the following is NOT a common characteristic of pathogenic bacteria?
Signup and view all the answers
What percentage w/v of salt concentration do some halophiles prefer?
Signup and view all the answers
Which group of prokaryotes is particularly important for the biogeochemical cycling of phosphorus?
Signup and view all the answers
What is a significant challenge when treating diseases caused by biofilm-forming bacteria?
Signup and view all the answers
Study Notes
Characteristics of Living Organisms
- Organization: Life is structured on a cellular level, with cells as fundamental units.
- Homeostasis: Cells maintain chemical balance and energy transformation in response to the environment.
- Reproduction: Organisms replicate, creating genetically similar copies using an instructional genetic code.
- Evolution: Genetic variations occur due to replication errors, driving the evolution of species.
Notable Organisms
-
Pelagibacter ubique:
- Smallest free-living organism; predominant in marine ecosystems.
- Combined weight exceeds all fish in oceans.
- Individual cell volume: 0.019 to 0.039 µm³.
-
Armillaria solidipes:
- Massive parasitic fungus with a network spanning ~10 km².
- Estimated age: ~2400 years; predominantly underground growth.
-
Posidonia australis:
- Aquatic plant spanning ~180 km².
Diversity of Life on Earth
- Life exhibits diversity in size, abundance, habitat, nutritional needs, lifespan, mobility, and variability.
- Common features among living entities: unity of organization, genetic material (DNA), and fundamental biochemical processes.
Essential Biomolecules
- DNA: The genetic material common to all living organisms.
- RNA: Transcribes DNA for protein synthesis, fundamental for cellular functions.
- ATP: Universal energy currency powering cellular processes.
Origin of Life
- Earth's age: ~4.5 billion years; oldest known fossils: ~3.7 billion years.
- Potential origins of life: geothermal pools or hydrothermal vents.
- Concept of "prebiotic soup" and the "RNA world" as theories for early life formation.
Last Universal Common Ancestor (LUCA)
- Existed ~4.2 billion years ago, unicellular, prokaryotic with a genome of around 2.5 million base pairs.
- All current life shares LUCA as a common ancestor.
Three-Domain System
- Organisms categorized as Prokaryotes (without a nucleus) and Eukaryotes (with a nucleus).
Prokaryotic Diversity
- First organisms on Earth; resilient to extreme conditions.
- Prokaryotes represent ~14% of Earth's biomass.
Metabolic Diversity of Prokaryotes
- Capable of various metabolic pathways, utilizing different energy and carbon sources.
- Examples include chemoautotrophs (e.g., Sulfolobus) and photoautotrophs (e.g., cyanobacteria).
Cyanobacteria
- First multicellular organisms, responsible for oxygen production through photosynthesis.
- Key contributors to Earth's primary productivity and historical carbon fixation.
Extremophiles
- Archaea thrive in extreme environments, such as high salinity, acidic springs, and cold habitats (e.g., Antarctic sea ice).
Role of Prokaryotes in Biogeochemical Cycling
- Crucial in nitrogen, carbon, and phosphorus cycling.
- Nitrogen fixation transforms atmospheric N₂ into biologically usable forms like NH₃.
Bioremediation
- Prokaryotes utilized for environmental cleanup, including oil spills and pollutants.
- Not all bacteria are pathogenic; many form biofilms that resist antimicrobial treatment.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge on the diversity of life in Organismal Biology. This quiz covers key characteristics of living organisms, including organization and homeostasis. Perfect for students taking BIO 211.
