Test #2 Flashcards
what components are required for scientific graphs?
Descriptive title, Axes titles & units, scaled numbers or labels on both axes, determine what type of graph you should construct, and graphs should be neat.
How do you construct appropriate scales for graphs?
Both axes begin at the origin (0,0), Each square on a given axis must represent the same amount, Calculate the difference between the smallest and largest values of the variable and divide the difference by the number of data points, Round up to the nearest convenient value (interval), and end the scale above the highest value.
How does the changing of the axes of a graph influence how data can be interpreted?
if the intervals on a graph are too far apart or too close together, there will be too much of a change or no change at all, making results seem like less or more than they really are.
What actions do scientists take to identify patterns in data?
Identify the independent and dependent variables, Identify if there is a key, Look where there a greater value (like a higher quantitative number) or where is there a lower value (like a lower quantitative value), identify changes, differences, or trends in the figure, and interpret by asking and answering, “What is the story this graph is telling?”
What examples of patterns did biologists see when investigating sexual selection trends?
Biologists saw that certain traits give males more reproductive success during mating, or they have intersexual relations.
Describe the nebular theory for the formation of our solar system
suggests that 4.6 billion years ago our solar system formed from the gravitational collapse of a giant interstellar gas cloud
What are the two general hypotheses about the way life-supporting molecules?
Miller-Urey and the Meteorite
Miller-Urey experiment
Miller and Urey built a model to show that organic compounds could be made by heating and passing electrical current, to stimulate lightning, through a mixture of gasses.
Meteorite analysis
Amino acids could have arrived on earth through meteorite or asteroid impact.
The two hypotheses for the formation of cell membranes
Iron-sulfide and lipid membrane
Iron-sulfide hypotheses
biological molecules combined in the compartments of chimneys made of warm sodium sulfide into a cool iron-rich solution on the ocean floor. The compartments acted as the first cell membranes.
Lipid membrane
lipid membranes spontaneously gave rise to liposomes giving rise to the first cells.
What evidence led scientists to propose that RNA, rather than DNA, was the first genetic material on early Earth?
Because RNA is a simpler form of DNA that does not need enzymes to replicate itself. It instead uses ribozymes to replicate.
What are the characteristics of life that we learned about in Unit 1?
orderly structure, reproduction, growth and development, metabolism, homeostasis, response to environment, and evolutionary adaptation.
How do the characteristics of life we learned in Unit 1 relate to Unit 2 and what we learned about early life on earth?
cells = lipid membrane hypotheses, reproduction implies that we need genetics to be passed on (DNA & RNA), and evolutionary adaptation
What are the domains of life? Which domains are single-celled and which contain multicellular organisms?
Archaea, Bacteria, and Eukarya. Eukarya is multicellular.
What organisms were the first photosynthetic organisms that added oxygen to the atmosphere?
cyanobacteria
What provides evidence that prokaryotes existed before eukaryotic organisms?
eukaryotes have both a nucleus, membrane bound organelles, and are multicellular, making them too complex to come before prokaryotes.
Describe the endosymbiont theory
suggests that mitochondria and chloroplasts were once simple prokaryotic cells that were engulfed by larger prokaryotes.
endosymbiosis
a relationship in which one organism lives within the body of another-with both organisms benefiting
Describe the autogenous theory
eukaryotic organelles evolved from infoldings of the plasma membrane, creating pockets that eventually pinched off.
Describe how the evolution of sexual reproduction led to increased diversity and variation
sexual reproduction allowed new combinations of genes to come together, increasing genetic variation
variation
the difference in the physical traits of an individual from those of other individuals in the group to which it belongs
Explain how there is evidence for evolution in the fossil record
the layers of rock fossils were found in proved rock layers each held their own types of fossils, also supporting the concept of decent with modification
evolution
the process of biological change by which descendants come to differ from their ancestors
Explain how there is evidence for evolution in biogeography
island species most closely resemble species on the nearest mainland
biogeography
migration between island and mainland species
Developmental homologous structures
similar features in the embryos of different organisms result from common ancestry.
Anatomical homologous structures
similarities in physical structures in the bodies of organisms imply common ancestry
Molecular homologies
similarities in DNA and cellular structures imply a common ancestor
Analogous structures are not evidence for evolution. Why not?
They are not evidence for evolution because they did not derive from the same original structure.
analogous structures
structures that perform a similar function but are not similar in origin
