Development of Biosphere
Which experiment demonstrated that organic molecules could form from simple gases thought to be present on early Earth?
Urey-Miller Experiment
What is multicellularity?
The condition of an organism being made up of multiple cells, often with specialised functions.
What is the name given to the long-term cycle of supercontinent formation and breakup?
The plate tectonic supercycle.
What is a mould fossil?
A negative impression left in sediment after an organism or part of an organism decays.
What principle states that geological processes occurring today also operated in the past?
Uniformitarianism.
What modern-day environment supports the hypothesis that life may have originated without sunlight?
Black Smokers (Hydrothermal vents)
What was one major characteristic of many Ediacaran organisms?
They were soft-bodied.
Name one way the position of continents can influence climate.
It can alter ocean currents, atmospheric circulation, rainfall patterns or temperature distribution.
What type of fossil provides evidence of an organism's activity or behaviour rather than its body?
A trace fossil.
What process causes a supercontinent to begin breaking apart?
Rifting.
What type of microorganisms carried out early oxygenic photosynthesis?
Cyanobacteria
What atmospheric layer eventually became possible because of increasing atmospheric oxygen?
The ozone layer.
Approximately how long does a complete plate tectonic supercycle take?
Hundreds of millions of years.
According to the principle of superposition, where are the oldest rocks found in an undisturbed sequence?
At the bottom.
What process allows cyanobacteria to produce oxygen?
Oxygenic photosynthesis.
What type of rock provides geological evidence of the interaction between early photosynthetic organisms and Earth's oceans?
Banded iron formations (BIFs).
What major biological event involved the relatively rapid diversification of many animal groups?
The Cambrian Explosion.
How can mountain building influence climate?
Mountains can alter atmospheric circulation, create rain shadows and increase weathering, which can influence atmospheric CO₂ over geological timescales.
What type of dating provides an estimated numerical age for a rock or geological event?
Absolute dating, commonly using radiometric dating.
Which Australian location is famous for its modern stromatolites?
Shark Bay WA
Why did increasing atmospheric oxygen create new opportunities for some organisms?
Oxygen allowed aerobic respiration to become increasingly important. Aerobic respiration provides more usable energy than anaerobic respiration, supporting organisms with greater energy demands and contributing to increasing biological complexity.
Name two adaptations that allowed plants to survive on land.
Any two of: cuticle, stomata, vascular tissue, roots, seeds or pollen.
Put these stages of the plate tectonic supercycle in the correct order: collision, rifting, continents dispersed, supercontinent forms, new oceans form.
Continents dispersed → collision/convergence → supercontinent forms → rifting → new oceans form.
What is the term for the time required for half of a radioactive parent isotope to decay?
Half-life.
Name the supercontinent
Pangaea