Exam 1 Study Guide

Question 1

what abiotic factors impact global patterns of animal distribution?

Answer 1

climate, temperature, precipitation, salinity, pH, sunlight

Question 2

What is a biome? And what are they characterized by in both aquatic (water) and terrestrial (land) areas?

Answer 2

biome: large scale communities characterized by climate

aquatic biome: differences in temperature, salinity, oxygen content, water depth, current strength, availability of light, freshwater or saltwater

terrestrial biome: differences in vegetation type, temp, and precipitation

Question 3

Understand the three-cell model and how to predict the latitude biome position.

Answer 3

• 0 to 20 degrees: warm and wet air = tropical rainforest
• 20 to 30 degrees: dry and hot descending air = deserts
• 45 to 55 degrees: air warms and gets moisture = temperate decidious
• above 60 degrees: dry and cold = polar regions
• from North to South pole starting at equator*

Question 4

What are the biotic factors that impact animal distribution?

Answer 4

food, competition, reproduction, habitat preferences

Question 5

Be able to explain how and why a mountain can show several major biomes from the bottom to the top of the mountain.

Answer 5

adiabatic cooling
- windward side: air increase through elevation, warmer air becomes colder and drops water (forest), at the top could snow
- leeward side: air begins to descend as it becomes dry/warm (deserts)

Question 6

What is the definition of a population and how are populations studied?

Answer 6

population: group of interbreeding individuals occupying the same habitat at the same time

population ecology: studies factors affecting population size and how it changes over time/space

Question 7

Explain the different ways that ecologists measure populations for specific organisms.

Answer 7

line transect: line that expands and you count how many plants/sessile organisms are touching it

quadrat: square of specific measurements thats places randomly and you count in there

pitfall trap: trap in the ground used for mobile small animals

mist nets: nets high up to catch birds/bats

mammal type: baited for small and big mammals

Question 8

What are the different types of dispersion patterns of organisms and which is most common?

Answer 8

clumped: resources are clustered in nature, social behavior promotes this pattern

uniform: competition may cause this pattern, animals defend their territories

random: rare but may occur where resources are common and abundant

Question 8

Define population density.

Answer 8

number of organisms in a given unit are or volume

Question 9

Be able to identify the 3 different survivorship curves. Also, explain and give an example organism that exhibits each type of curve.

Answer 9

type 1: die late in life, parental investment, less offspring
type 2: uniform rate of decline
type 3: huge decline in young

Question 10

Understand the variables that go into a life table and how to interpret those variables in a life table.

Answer 10

n0= # alive at year zero
# of dying: prev pop - new pop
age-specific survivorship: nx/n0
age-specific fertility: survivorship x fertility @ that age
net reproductive rate: =1 (stable), < 1 (decrease), > 1 (increase)

Question 11

Be able to distinguish between exponential and logistic growth models. Understand the mathematical model for each and what the terms mean.

Answer 11

exponential growth: population grows faster and gets larger

logistic growth: populations will be limited by carrying capacity (will have K in the mathematical model)

Question 12

What is the definition of and factors that are density dependent and density independent?

Answer 12

density dependent: high density = low birth rate = high death rate = stable/decline

density independent: abiotic factos

Question 13

What is meant by carrying capacity? What is it that causes a population to have a carrying capacity?

Answer 13

carrying capacity: max population size sustained by the environment

cause: limiting resources (food, habitat, etc), or species interactions

Question 14

Be able to explain the competitive exclusion principle & how resource partitioning affects this principle.

Answer 14

competitive exclusion principle: if two species have an ecological niche that is too similar, the two species can’t coexist

resource partitioning: differentiation of niches, both in space and time that enables similar species to co-exist

Question 15

Interactions between species can be defined by the effect on the populations concerned. Be able to name and identify the + or – interactions between species.

Answer 15

mutualism: +, +
commensalism: +, 0
amensalism: -, 0
competition: -, -
predation, herbivory, parasitism, parasitoid: +, -

Question 15

Understand the different adaptations that prey species have gained to reduce predation on the population and be able to give an example of each.

Answer 15

chemical defense: skunks
aposmatic coloration: warning color to advertise they are toxic, that one frog from rio
camouflage: blend into environment, that stick animal
display of intimidation: make them bigger, puffer fish
mullerian mimicry: look similar and both are toxic, some butterflies
batesian mimicry: look similar but only one is toxic, snakes
armor/weaponry: shells, stingers, horns

Question 16

Explain the patterns of species richness and how they vary.

Answer 16

• species richness increase from polar regions to the tropics
• species richnnes increase with topographical variation, more habitat
• # of species in influences by peninsular effect ( decrease away from mainland)

Question 17

How do you calculate species diversity?

Answer 17

using the shannon diversity index
Hs: - SigmaPilnPi

Question 17

What is species richness? species diversity? What is the difference between the two?

Answer 17

species richness: # of species in a community

species diversity: the variety of species that make up a community (includes species richness and relative abundance)

Question 18

What is the name of the process that occurs after disturbances that is the system trying to reset itself? Be able to distinguish between primary and secondary when it comes to this process.

Answer 18

succession (recovery)

primary: area with no soil, volcanic eruption or glacial retreat

secondary: soil is left intact, fires and floods

Question 19

Understand the feeding relationships among the various species in a community and how they impact each other. They can be represented by chains or webs.

Answer 19

food chains: trophic structures that determines the flow of energy and nutrients

food webs: more complicated relationships with multiple links among species

Question 20

Be able to explain the 3 different successional models: Facilitation, Inhibition & Tolerance.

Answer 20

facilitation: one species positively impacts the fitness of another

inhibition: first colonist prevent others from colonizing, first come

tolerance: species replacement is unaffected, anyone can come in

Question 21

When it comes to food chains and webs understand the following terms: Producers, consumers, primary consumers, secondary consumers, tertiary consumers, decomposers.

Answer 21

producers: plants or phytoplankton, make the food
consumers: eats the producers or other consumers
primary consumers: only eat the producers, mainly herbivores
secondary consumers: eat the primary consumers
tertiary consumer: eats the secondary consumer
decomposers: consume dead plants and animals, eat waste products

Question 22

Understand the energy transfer of food webs and why energy is lost as you go up the food chain/web.

Answer 22

only 10% of energy is transferred from one trophic level to another
- becomes waste, cellular respiration, etc

Question 23

What is age structure and TFR and how does it influence the predictions on future human population?

Answer 23

age structure: predicts the population growth

total fertility rate: average # of live births a woman has during her lifetime
- = 2.3 (zero pop growth), < 2.3 (pop decrease), > 2.3 (pop increase)

Question 23

Discuss the main factors that are correlated to lower population growth.

Answer 23

income, female literacy rates, religious beliefs,
- Increase per capita income and literacy = decrease pop growth

Question 24

What are the 4 main human caused factors to the loss of biodiversity? Be able to explain and give examples of each one?

Answer 24

1. habitat degradation: natural habitat is altered so it can’t support original species
   - deforestation, agricultural conversions, urbanization
2. introduced species: species moved by humans from native habitat to another location
   - become invasive
3. overexploitation of species: harvest species that is not sustainable based on natural rate of mortality and capacity of reproduction
   - hunting and fishing
4. pollution: causes global warming, eutrophication, biomagnification, etc

Question 25

What is an ecological footprint and what is the average footprint worldwide?

Answer 25

aggregate total of productive land needed for survival in a sustainable world
- avg. 2.75 ha

Question 26

What are the 3 main biogeochemical cycles discussed? For each one, understand why the cycling of that chemical is important to life, what the abiotic reservoir is for each one, and how humans have influenced/altered the cycle.

Answer 26

1. carbon cycle: cycles through photosynthesis and cellular respiration, burning fossil fuels and deforestation increase CO2 in atmosphere
2. phosphorus cycle: weather of rocks release phosphate into the soil and move through the food chain, agricultural runoff leads to elevated nutrients
3. nitrogen cycle: goes through bacteria into the soil/plants then consumed by animals (repeat),

Question 26

What is Biomagnification? How does it work in a food web or chain?

Answer 26

biomagnification: certain chemicals concentrate in organisms @ higher trophic levels

Question 27

What are the three main consequences of global warming?

Answer 27

1. sea levels will rise
2. promote climate change and alter global precipitation
3. alter species distribution

Question 28

What is the greenhouse effect and what are the greenhouse gases?

Answer 28

greenhouse effect: solar radiation passes through the atmosphere and heats the Earth’s surface
- carbon, phosphorus, and nitrogen