Biology 1002B Lecture Notes - Ribozyme, Electrostatic Discharge

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beigereindeer807

6 Feb 2012

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The origin of life y 4. 6 billion years (age of the earth) condensed into one year. March 2: 3800 million years ago . April 28: 2700 million years ago o2. Luca stands for last universal common ancestor y three domains of life on earth: bacteria, archaea and eukarya y y all forms of life are a descendant of luca y all forms of life: October 15: 600 million years ago animals. Dna to rna to protein transfer of genetic system based on dna information common system of protein assembly / contain ribosomes contain proteins. Life evolved within 600 million years y y stromatolites (3. 5 billion years ago) structures produced by microbial activity, specifically cyanobacteria. Geophysical stage y conditions on the young (primordial) earth: This is what we call a reducing atmosphere - filled with electron-rich hydrogen atoms so the atmosphere is conducive, allowing the build-up of complex, highly reduced molecules.

Related Questions

1.All living organisms alive today are assumed to have evolved from some one-celled ancestor that lived about four billion years ago and has been called the Last Universal Common Ancestor or LUCA. LUCA has been extinct for a long time but evolutionary biologists have hypothesized as to what it was like. Given the characteristics of modern prokaryotic and eukaryotic organisms, what cellular characteristics would you suggest that LUCA had? What type of cellular respiration might LUCA have used? Why?

2. Why is water so essential for biological life? Provide examples as to how water is used in living systems.

Angiosperms and their animal pollinators have coevolved in the terrestrial environment for Select one: a. 150,000 years. b. 1.5 million years. c. nearly 15 million years. d. more than 150 million years. e. more than 1.5 billion years.

An African monkey has a DNA sequence that is 96.66% similar to a human sequence. According to the molecular clock, about how long ago did the common ancestor for African monkeys and humans live?

2.5â3 million years ago

5â6 million years ago

13â16 million years ago

17â20 million years ago

Humans and chimpanzees have a common ancestor that lived approximately 5 million years ago. Scientists have amassed an impressive collection of fossils for ancestors to modern humans and placed these ancestors in chronological order to observe the changes that occurred as these organisms evolved more human-like characteristics. Which lines of evidence provide the basis for stating that humans and chimps have a common ancestor that lived approximately 5 million years ago?

homologous structures in humans and chimps

DNA sequence similarity

changes in bone structure

vestigial structures in humans

Which description applies to a vestigial structure or trait?

It is the result of convergent evolution.

It represents evidence supporting the common descent and separate types models for modern organisms.

It did not have a necessary function in more ancestral organisms, but it does in more evolved organisms.

It is a type of homologous trait that is found in diverse organisms.

Which organisms are most closely related?

Bears and raccoons, which are both in the order Carnivora

Cougar and lynx, which are both in the family Felidae