Edit this page with your answers to Chapter 4.
Brittney and Maria- I've finished the study guide so i just pasted the answers that I found- but please add because there is probably info missing.
1. Chemical evolution of the organic molecules, biopolymers, and systems of chemical reactions began to form the first cells.
2. Tools available for researchers to research history: Fossils, Chemical analysis, cores drilled out of buried ice, and DNA analysis.
3. Theory of Evolution: All species descended from earlier, ancestral species. Variation within the gene pool, natural selection, and adaptive radiation cause differentiation between species. Extinction and speciation cause species to either end or develop.
4. Natural selection occurs when some individuals of a population have genetically based traits that increase their chances of survival and their ability to produce offspring with these traits.
Requires 3 conditions:
Genetic Variability
A heritable trait Differential reproduction (the most offspring.)
5. Coevolution: When changes in the gene pool of one species leads to changes in the gene pool of another. (The species have usually been interactive for many generations).
5. Coevolution: When changes in the gene pool of one species leads to changes in the gene pool of another. (The species have usually been interactive for many generations).
6. Specialist species occupy narrow niches. They have advantages in highly competitive environments. Generalist species have broad niches. They have advantages in changing conditions.
7. Ecological Niche: A species way of life or functional role in a community or ecosystem and involves everything that affects its survival and reproduction. A fundamental niche consists of the full potential range of physical, chemical, and biological conditions and resources it could theoretically use if it could avoid direct competition from other species. A realized niche: a part of a species fundamental niche in a particular community or ecosystem.
8. Speciation: when two species arise from one. A new species arises when members of a pop are isolated from other members for so long that changes in their genetic makeup prevent them from producing fertile offspring if they get together again.
9. Extinction: a process in which an entire species ceases to exist. Background extinction: species disappear at a low rate Mass extinction: significant rise in extinction rates above the background level. Humans are increasing the rate of extinction for many species due to the damage they’ve caused the earth.
10. Artificial selection and genetic engineering have helped create nutrient-rich crops, more effective pharmaceuticals, and even pollution clean-up materials. But many ethical issues are raised concerning the control of human genetics and discrimination against certain genes.
11. Humans have had a profound influence on their environment due to strong opposable thumbs, the ability to walk upright, and complex brains.
~Christine Donaldson (period 5)
