Biology 102Study Guide Exam 1Main topics for Study Guide:I. Population EvolutionDisclaimer: Dr. McAlvin provided a study guide for the class to study. This study guide is going tobe based on the questions on the study guide. A lot of the topics on this study guide are the answers to the study guide but will provide some further explanation. I will review the first part of the Dr. McAlvin’s study guide because I figured that’s the material that most people will need to review.Population Evolution- Adaptation- something that changes or when you acquire a new trait that makes you more fit for your environment.- Different kinds of adaptations:o Behavioral adaptations (ex. ability to learn)o Structural adaptations (ex. giraffes with longer necks)o Biochemical adaptations (ex. faster metabolism)o Physiological adaptations (ex. venom in snakes)- Darwin- proposed natural selection- Natural selection- differential survival and reproduction of individuals in response to environmental pressure that leads to change in allele frequencies in a population over time. o Ex. beetles that are resistant to pesticide. One beetle may be resistant because it has a mutation that gives it that gene purely by chance. That beetle survives the pesticide being sprayed and lives to reproduce, when thatbeetle reproduces it passes on the gene making its offspring resistant as well. SO over time the beetle population is mostly resistant to the pesticide.- Went to the Galapagos Islands with his teacher where he collected insects and plants. Predominantly known for his study on the finches of the island and how their beaks were different.o Believed in change in organisms over time, they change their traits to accommodate to their environment. The ones who can adapt and have the better traits survive.- Variation-extensive in all population- It’s not just color but also behaviors- Happens by mutations of certain genes in DNA- Influences on Darwin’s thoughts on EvolutionBiology 102- Lamarck: proposed that giraffes developed necks over time in order to reach leaves on tall trees.- Lyell: geologist, studied fossils sand Earth’s geographical processes, his idea was that the Earth was a lot older than previously thought and constantly changing.o Darwin believed this and basically connected the dots with natural selection.- Natural selection can cause variation in 3 ways:- Disruptive selection- favors individuals at both extremes (typically two populations) of the phenotypic range.o Patchy environment- slit amongst distinct groups- Directional Selection- acts against individuals at one of the phenotypic extremes.o When environment changes and moves toward a new trait- Stabilizing selection- favor intermediate phenotypeso When the environment stays the same and the variation of the predominant trait will become more frequent eventually getting rid of the other traits- Homology- the similarity in characteristics that result from common ancestry- Different function but similar structure due to common ancestry- Analogy- similar function but different structure- Ex. dragonfly wing and bat wings: analogy because they are both used to fly but structurally are very different- Molecular Biology- comparisons of DNA and amino acid sequences between different organisms- Comparative Anatomy- the comparison of body structures in different species - Ex. comparison of a cat limb, human arm, whale flipper, and bat wing. They all have similar structures (i.e. phalanges, carpals, metacarpals, etc.)- Comparative Embryology- the comparison of early stages of development among different organisms- They all look similar in the beginning but due to the genes that embryo has it develops into a different species.- Fossils- a reminant of an organism that has solely by chance remained intact.- Obtained by digging primarily - It’s placement in the rock formations (or the level or deepness of the fossil) is known as fossil records - Vestigial trait- a trait or characteristic that is no longer evident in the use or function of the organism - The tailbone in a human, evolved from our ancestors who had tails that they needed but now we no longer have tails and it no longer has purpose but it is stillthere.o Whales evolved from land animals through a Gradualistic pattern Gradualistic: when the event or changes occur slow or accumulate changes from one population to the next- Evolution- change in allele frequencies in a population over time.Biology