1. DP Biology HL; Cells Flashcards
Describe the Conditions on early Earth and the pre-biotic formation of carbon compounds
lack of free oxygen and therefore ozone, higher concentrations of carbon dioxide and methane, resulting in higher temperatures and ultraviolet light penetration. The conditions may have caused a variety of carbon compounds to form spontaneously by chemical processes that do not now occur.
when did the sun and earth form
C. 4.5 billion years ago
What compounds and elements are essential to life
hydrogen, phosphates, nitrogen, carbon dioxide, methane, and ammonia.
Autotrophs are and include
organisms that generate their own energy; e.g. plants
Heterotrophs are and include
organisms that consume other organisms for energy (like animals)
What are hydrothermal vents and why are they important to life
crevasses at the ocean floor where water seeps in and meets magma, the water is then ejected back out at high temperatures (energy) along with minerals and compounds, creating a chemical gradient (e.g. Fe, Ba, Ca, Si, H2, CO2, and CH4). These would have provided life with energy, away from UV radiation.
What is LUCA, how do we know about it, and what does it implicate
the Last Universal Common Ancestor is the farthest back of life we can trace. Scientist have identified common genes across all three existing domains of life (Archaea, Bacteria, Eukarya), suggesting inheritance from a common ancestor. These genes implicate that LUCA lived in a hot, oxygen-free place, and harvested energy from a chemical grad. like the ones at hydrothermal vents.
Where was LUCA most likely formed
Next to a white smoke, most likely in lost city (mid-atlantic ridge)
What are the most common characteristics of life (HOMREDS)
Homeostasis, organization, metabolism, reproduction, evolution, development (growth), response to stimuli
Explain Darwinian evolution
Natural selection; when livivng things reproduce, they pass on traits. Ones with negative traits are more likely to die and not pass the trait on, whereas positive traits build up over time.
What and how did Friedrich Wöhler
by producing urea in the lab, Wöhler proved that life is powered by regular chemical reactions rather than a mysterious force.
What developments are required for the origin of cells (SCSC)
Self-assembly of carbon compounds into polymers
Compartmentalization to isolate the compound from the environment
Self-replication of a genetic material that could evolve
Catalysis for controlling chemical reactions
What was the function of the Miller Urey experiment
To simulate conditions on the prebiotic earth with water (the ocean), fire (to produce evaporation), various gasses believed to be present in abundance on the prebiotic earth, an electrode (lightning, volcanic eruptions etc.), and a condenser (colder conditions). over time, producing biomolecules.
Describe the formation of vesicles
These vesicles are formed by phospholipid bilayers with water inside and outside the vesicle; the phospholipids have hydrophilic heads and hydrophobic tails. Hence, the first layer has the heads facing the outside of the vesicle, the second layer, on the other hand, has the heads facing the inside of the vesicle.
RNA acted as both genetic material and _______ in the earliest cells due to its catalytic activity. An example of this is _____ and is used for _____
as enzymes; Ribozymes in the ribosome still used to catalyse peptide bond formation during protein synthesis.
DNA and enzymes vital for life; enzymes needed for __ but (same word) is needed for __
DNA replication - DNA needed for enzyme production.
RNA-based viruses, like coronaviruses, mutate — due to —
Rapidly, error-prone replication
Scientists believe that __ Predates the first living cells as the basis of life
RNA
