Lecture 1 Flashcards
- What is the definition of evolution?
Its a change in genetic frequencies
- What is the definition of natural selection? (our class definition)
The mechanism of evolution and how it occurs.
- Which statement does not describe the natural selection example discussed in class (the one about the black and brown mice)?
start with three black mice and six tan mice; black mice can hide better from predators than the tan mice
The next generation will have seven black mice and two tan mice b
- According to the video Natural Selection, if there are organisms which are considered the same species, which statement describes one of the things they can do?
They can breed, pass down DNA to offspring, have a variety of traits
- According to the video Natural Selection, what does fitness mean in the biological sense?
By how many offspring they have
- What is artificial selection?
When humans pick the genes they want to be expressed
- Fossils provide direct evidence of evolution. How does one make a fossil?
First the organism has to be buried in sediment
Second the calcium in the bone or other hard tissues must mineralize
Third the surrounding sediment must harden to form a rock which means usually has to be applied under a great deal of pressure
- What is a difference between relative and absolute dating of fossils?
Relative dating- if a fossil is closer to the earth’s surface; it is newer. And if a fossil is farther from the earth’s surface; it is older.
Absolute dating- this is when you are looking at the radioactive decay when looking at the half life
- What is the definition of a homologous structure?
Are structures with different appearance and functions that all derive from the same body part in common ancestors
- What is the definition of a vestigial structure?
Body part or structure that is no longer used by an organism
- Which statement describes an examples of a vestigial structure?
The human appendix
The pelvis of a whale (This also shows how humans are related to whales)
- According to the video Molecular Evolution: Genes and Proteins, when scientists compare the entire genome of backer’s yeast and a worm, what did they find?
Worms contain most of the same genes but the reverse is not true, since the worm is a more modern creature.
- According to the video Molecular Evolution: Genes and Proteins, how can the genome of cytochrome C tell us how organisms are related?
These mutations tell the genealogy of the owners.
- What is a difference between convergent and divergent evolution?
Convergent evolution- occurs when species have different ancestral origins, but have developed similar features
Divergent evolution- occurs when two separate species evolve differently from a common ancestor
- According to the video Molecular Evolution: Genes and Proteins, when scientists compare the entire genome of backer’s yeast and a worm, what did they find?
Worms contain most of the same genes but the reverse is not true, since the worm is a more modern creature.
- Which statement describes an example of convergent evolution?
Sharks, tunas, porpoises and dolphins are similar in structure, they have fins, asymmetrical tails but in general they are going to be streamlined to move through water.
- Which statement describes an example of divergent evolution?
Its believed that only finch species eventually came to the galapagos from ecuador and over time ended up with 20 species of finch by random mutations
- Which statement accurately describes the current theories for where life originated on earth four billion years ago?
They think life arose in bubbles that are constantly forming at the ocean’s edge
- Which theory is regarded as the most viable (currently) for where and how life originated on Earth? Why?
At deep sea vents this is becoming a much more popular place to be considered the origin of life since they have everything that is needed.
- What is the definition of a mass extinction?
Extremely sharp decline in species diversity
- Which of these is not a mass extinction which occurred in the past?
Permian (Most severe)
Cretaceous
Triassic
Devonian
Ordovician
(Anything else mentioned DID NOT occur)
- The most severe extinction occurred at the end of the _____ period approximately 250 million years ago (96-98% of all plant and animals went extinct). Fill in the blank.
permian
- We are currently in the sixth mass extinction called the ____. Fill in the blank.
Anthropocene
