Ecology EXAM 1 Chapter 1 Guide PDF

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ECOLOGY EXAM 1 CHAPTER 1 GUIDE INTRODUCTION (Chapter 1) 1. Define Ecology, and how it is different from environmental activism.

a. differentiate between biotic and abiotic (terms). Ecology: the relationship between organisms and their environment. -biotic = life related -abiotic = not regarding life – pH, light, water, humidity, temperature

2. Why is “ecology” considered to be a science? because ecologists employ the scientific method.

3. What does ecology consider to be the fundamental unit of study - Individuals and how do independent survival and natural selection enter into this consideration?

a. discuss how one can have 3 organic individuals and yet only 1 genetic individual? Triplets = same genome, they’re 1 genetic individual 3 organic individuals 4. Define population and give a local example. Population : is a group of individuals of the same species, that is potentially immortal and capable of evolutionary change. Example: bristlecone pines on top of the Spring Mts;

a. how old (minimum and maximum) is the population of bristlecone pines in the Spring Mts? 5000 years old b. explain how evolution applies to a population (what is our operational definition) but not an individual? that is, how is it that an individual is subject to selection, but only a population is subject to evolution? 5. Define community and give a local example. – a group of co-occurring populations of different species Example: juniper woodland

6. Define ecosystem and give a local example. Ecosystem :comprised of groups of organisms in a similar environment. Example: Virgin River

a. what are the two dominant species of the Mojave Desert ecosystem? 1. Creosotebush 2.Bird Sage ** b. what are the three defining species of the Virgin River shoreline ecosystem (one is an invasive species)? 1. Cotton woods 2. Willows 3. Spider? - Invasive species

7. Differentiate the five major groups of organisms by their major functions in ecosystems [a 197 primer]. 1. Biosphere approach 2. Organism approach 3. Population approach 4. Community approach 5. Ecosystem approach 8. Differentiate between niche and habitat of an organism, and give an example not used in class. Habitat : Where the organism lives Niche: Functional role of organism Example:

9. Define natural selection. → Differential survival and reproduction → Process by which better adapted individuals survive and reproduce in an environment more successfully than others; It explains HOW evolution occurs.

10. Give an example of natural selection not used in class.

Giraffes that inherited slightly longer necks or longer legs can reach more food during a drought than the shorter giraffes. The short giraffes die. The tall giraffes live, have babies and pass on the tall gene DNA.

11. What is an adaptation, and how might it be an outcome of natural selection? Adaptation arise by natural selection and confer survival Inherited characteristic that INCREASES an organism's chance of survival or reproduction in its environment

a. explain why all traits of species may not be adaptive? Some genetic variation present in populations does not affect survival and reproduction one way or the other, then the variants are not adaptations; they are simply neutral variation that is maintained by mutation and genetic drift.

b. for the mantid pictured on this slide (slide 15), explain how its appearance gives us a hint as to its palatability.

12. Outline the scientific method, including the correct order of the following: prediction, hypothesis , observation, question, experimental design.

1. Observation 2. Question 3. Hypothesis 4.Prediction 5. Experimental design a. what is “replication” in an experiment and how high should this number be?

Repeat for total of 4 trials b. define “control” and define “treatment” in an experiment?

The control group is identical to all other items or subjects that you are examining with the exception that it does not receive the treatment or the experimental manipulation that the treatment group receives. ... The treatment group is the item or subject that is manipulated. ** 13. Frequent issues that arise in the design of an experiment (e.g., about an animal’s stress physiology) include how you selected the animals used in the experiment, genotype, animal size, animal age, where animal was collected, how long was animal in captivity, previous stress history. Are these factors important, and how would you control for them?

2. PHYSICAL ENVIRONMENT and BIOMES (Chapters 2, 3) 1. Why is Lake Mead so high in calcium concentration, and what is that white crust that forms on soils that have been irrigated around Las Vegas?

Because of the lime stones

a. what is “hardness” and “softness” regarding water? Hardness : Lots of dissolved salts Softness: Feels slippery, hard to get soap off 2. What are the two major ions that seawater contains? Cl ions & Na ions 3. Define pH. Concentration of sodium ions 4. Give a chemical equation that explains why the pH of Lake Mead is fairly high (7-8)? H+ + CaCO3  Ca+ + HCO35. In words and basic equations, explain photosynthesis and respiration.

CO2 + H2O -> C6H12O6 + O2 Photosynthesis makes sugar and oxygen C6H12O6 + O2 -> CO2 + H2O Respiration makes carbon dioxide and water

6. What makes us call certain types of matter organic and other types not organic? Organic compounds will contain a carbon atom. Inorganic will not contain carbon. a. Give an example of each type (an organic and an inorganic compound) For organic: Carbon For inorganic : Sulfur 7. Explain what happens to oxygen concentration in a lake (or in waterlogged soils) as water depth increases, and why this pattern occurs. Low light limits photosynthetic production of oxygen. Animal and microorganism closer to the top consume oxygen so by the time it gets to the animals/microorganism at the lower depths it is little.

8. Compare the number of phyla in marine, freshwater, and terrestrial habitats and perhaps why this might be the case, in your answer defining endemic. [fig. 3.9] in the marine habitat it supports many more phyla and that probably life comes from the ocean. Endemism means that it is only found in that region **a. according to a recent news article, 90% of Madagascar plants are endemic: how does this relate to the time of isolation of this island from Africa? ** b. comment on why a species might be “real” but a phylum may be a human abstraction/concept. 9. What causes the seasonal cycles in water temperature and nutrient mixing in temperate lakes? Thermal stratification

10. Briefly characterize these temperate lake seasonal cycles using winter, summer, and spring/fall times of the year. [fig. 3.38] in the winter :coldest water at surface, warmest water at bottom. In spring/fall : winds create mixing, equalizing temperature, nutrients, and oxygen. In summer : thermal stratification occurs.

11. Briefly characterize the three major zones of a temperate freshwater lake and the names of these zones. [fig. 3.37] Epilimnion - Top Layer Sunlight penetrates and warms the water Metalimnion- Middle layer Temperature , other physical and chemical factors change rapidly with depth Hypolimnion- Bottom Layer

Water is cold and dark and may lack dissolved oxygen

12. Define oligotrophic and eutrophic lakes in terms of oxygen levels, nutrient levels, and the kind of fish one might find there. oligotrophic lakes : they are well mixed and well oxygenated, lower in nutrients, and trout habitat. eutrophic lakes : they are oxygen depleted, high in nutrients, and catfish, carp habitat

13. Explain the paradox of the Las Vegas Wash: why do we see high nutrients and low oxygen concentrations here; or, how it is possible for fish to die at the base of the Las Vegas Wash, when nutrients are high and algae - fish food - are abundant? When algae dies in the water, it takes up a lot of oxygen, leaving all the fish to die.

14. Which two global factors produce latitudinal variation in climate? Uneven heating of earth surface along with tilt in earth's axis produce latitudinal variation in climate a. how would seasonality in T and precip. be affected if earth’s rotation on its axis was perpendicular to its plane of orbit about the sun? b. why does the annual rainy season in regions near 23 degrees N latitude begin in June? 15. Generally speaking, how do mountain ranges influence local temperature and precipitation patterns?

16. Briefly characterize the O, A, B, and C soil horizons. 1. O Soil horizon Organic horizon. Upper layer contains loose, somewhat fragmented plant litter. Litter in lower layer is highly fragmented 2. A Soil Horizon Mineral soil mixed with some organic matter. Clay, Iron, aluminium, silicates, and soluble organic matter are gradually leached from A horizon. 3. B soil horizon Depositional horizon. Materials leached from A horizon are deposited in B horizon. Deposits may form distinct banding patterns 4. C soil horizon Weathered parent material. The C horizon may include many rock fragments. It often lies on bedrock

a. why is an O horizon generally absent from desert soils except perhaps directly under a shrub? 17. Why don’t we use animals as indicator species for biomes? We don't use them because animals migrate 18. In general, which two abiotic factors define a particular biome? see figure following point 13 of lecture. Temperature and precipitation

19. Why are cold and wet biomes nonexistant? (i.e., very cold and very wet) 20. Given a climate diagram from a city anywhere, be able to identify the information on T, rainfall, time of year, elevation, etc. [fig. 2.6]

21. Be able to distinguish, given a climate diagram, which of the three biomes we covered in class this diagram identifies. 22. Briefly describe each of the three biomes covered in class (in terms of vegetation, soils, seasonality, diversity, a country or city or two within its boundaries). 23.

a. indicate why precipitation is so unpredictable in the Mojave Desert. b. discuss why prescription drugs are so often derived from plants in the tropical rainforest biome, including in your answer how competition might select for different drug combinations....