Ecology Exam 1

ecology def

the scientific study of interactions among orgs and the environment

field is always changing

ecological systems

biological entities that have their own internal processes and interact with their external surroundings

individual

a living being

__**the most fundamental unit of ecology**__

__**unit of natural selection**__

smallest level at which we can study ecology

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individual species

a grp of orgs that interbreed with each other and produce fertile offspring

can be complicated: ex: dogs are same species but can look diff, some birds can look the same but are diff species

population

individuals of the same species living in a particular area

__**unit of evolution**__

evolution can impact the pop level→ when multiple individuals have adaptations that could influence at the pop level

factors: geographic range, abundance, density, change in size, composition

community

all pops of species living together in a particular area

all interact w each other

hard to pinpoint where one community starts and other begins→ can be very gradual

ecosystem

one or more communities of living orgs interacting w their non living physical or chemical environments

__**Abiotic factors added**__

pH, salinity levels, soil levels, weather

landscape

mult ecosystems that are connected by the mvmt of individuals, pops, matter, and energy

mvmt of individuals key

biosphere

all the ecosystems on earth

landscapes interacting, climate, large scale migration

individual approach to studying ecology

emphasizes the way in which an individuals morphology, physiology, and behavior enable it to survive in its environment

adaptation

a characteristic of an org that makes it well suited to its environment

population approach to studying ecology

emphasizes variation over time and space in the number, density, and composition of individuals

sex ratio, birth/death rates, immigration and emigration, genetic makeup

community approach to studying ecology

emphasis on diversity and relative abundances of diff kinds of orgs living together in the same place

how many species are there, looking at diversity in comm

ecosystem approach to studying ecology

emphasis on storage and transfer of energy and matter

landscape approach to studying ecology

concerned with the mvmt of energy, matter and individuals btwn diff ecosystems

biosphere approach to studying ecology

largest scale, mvmts of air and water and the energy and chemical elements they contain

weather

short term patterns of the atmosphere

time and location

variation over period of hours or days

climate

long term patterns of weather (30 y or more)

average weather

greenhouse effect

process of solar radiation striking earth, being converted into infrared radiation and being reabsorbed by atmospheric gases

factors that determine the climate of an area

latitude, land water distribution, atmospheric components, prevailing winds, ocean currents, altitude/topography

latitude influence on climate

the suns light is diffused towards the north and south poles

the suns rays are strongest at the equator and then diffused towards the top and bottom of the earth

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during diff times of the year, earth is closer or farther away from the sun

land-water distribution influence on climate

uneven heating drives weather and climate

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land surface= low SH= quickly heat up

water= high SH= take longer to heat up

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sc is by the coast- temps do not fluctuate as much

midwest varies a lot in temp

specific heat

items with low specific heat will quickly warm up

high SH take longer to warm up

atmospheric currents influence on climate

circulations of air

warm air rises= less dense= more active atoms

cold air sinks= more dense= less active atoms

at equator → heats up more

• hot air rises

• as it rises, it cools and condenses→ rain

• cool air sinks and begins to warm and flow back towards equator

• ^^process called hadley cells

hadley cells

• hot air rises

• as it rises, it cools and condenses→ rain

• cool air sinks and begins to warm and flow back towards equator

30˚ N and 30˚ S

high pressure

creates deserts at 30 ˚ N and S

intertropical convergence zone

area where 2 hadley cells converge and cause large amts of precipitation

global currents (air)

hadley cell- 0 and 30

ferrel cell - 30 and 60

polar cell- 60 and 90

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low pressure = rain

high pressure= dry = air moving back down towards surface

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coriolis effect

the deflection of an obj path due to the rotation of the earth

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north-

high P= clockwise

low P= counterclockwise

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south-

high P= counterclockwise

low P= clockwise

ocean currents

unequal heating, coriolis effect, predominant wind directions, topography of ocean basins, diffs in salinity

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we have 8cm more of water at equator

high heat moves to low heat

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thermohaline circulation- global pattern of surface and deep water currents that flow as a result of variations in temp and salinity that change the density of H2O

* if some cities are on same latitude, why do they not have the same temp?→ warm water flows towards europe, cool water towards NA

altitude

higher elevation= less SA= less infrared radiation = colder the temp

rain shadow effect

a region w dry conditions found on the leeward side of a mountain range as a result of humid winds from the ocean, causing precipitation on the windward side

biome

geographic region that contains communities composed of orgs w similar adaptations

categorized by major plant growth forms

convergent evolution

a phenomenon in which 2 species that are not releated, look similar due to similar selective forces they have evolved under

what are limiting factors of plant growth?

sunlight and moisture

tropical rainforest biome

close to equator (amazon)

warm and humid, large amts of rain

neutral, not nutrient rich soil due to vegetation quickly taking up nutrients

greatest biodiversity

poison frongs, jaguar, sloth

desert biome

midlatitudes (sahara)

very dry and arid, high rates of evaporation

soil is rich in minerals

cacti, tumbleweeds

tortoise, fennec fox, gila monster

tropical seasonal forest: savanna biome

africa, northern australia

warm all year round, dry and wet season

porous, low fertility soil

eucalyptus trees, grasses, baobob trees

warthogs, sebras, elephants

woodland- shrubland biome

west coastal regions (southern cal, mexico)

hot and dry summers, cool moist winters , little rain

fertile, mildly acidic soil

shrubs and short trees

deer, goats, amphibians

temperate grassland biome

midlatitudes (midwest, nebraska)

cold winters, warm summers, some rain

deep and dark fertile soil

buffalo grass, sunflowers

deer, prairie dogs

northern coniferous forest biome

northern continents (pacific northwest of america)

cool and moist all year

fungi

pine, spruce, fir, hemlock

black bear, red fox, grizzly bear, bobcat

temperate seasonal forest

eastern NA

mild winters, hot and humid summers

rich soil

broadleaf trees, mosses, mountain laurel

raccoon, moose, mountain lion, squirrel

Tundra

poles of earth

subfreezing temps and low precipitation

nutrient poor soil

arctic moss, cotton grass, lichen

arctic hare, arctic wolf, reindeer

temperate rainforest

along coastlines, new zealand, pacific coast in NA

long wet winter, short dry summer

fertile soil

sequoia trees, douglas fir , mosses, evergreen huckleberry

flying squirrels, great horned owls, black bear

what properties affect how aquatic orgs live?

density

viscosity

depth

inorganic nutrients

temp

density

covalent bonds btwn O and Hs in H2O

hydrogen bond btwn 2 h2O molecules

less dense obj= floats

dense obj= sinks

swim bladder in fish

• filled with o2= less dense= floats

• deflated swim bladder= denser= sinks

manatees fart to sink in the water

viscosity

the thickness of a fluid that causes obj to encounter resistance as they move through it

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streamline moves better

large projections= causes drag

depth

conditions:

no light, cold, high pressure, limited O2

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anglerfish- produce own light

coral- uses sulfur

deep sea snailfish- has gap in skull, as they get deeper pieces overlap, bones made of cartilage, hypermobile

inorganic nutrients

water is powerful solvent - can dissolve many subs

water is polar

salt breaks up water structure

osmoregulation- the mechs that orgs use to maintain proper solute balance

• fish in high solute enviornment- excrete most of solute out in urine, take in water through mouth , solutes goes out through gills and urine

• fish in low solute enviornment= retain most of solute taken in via gills and mouth

osmosis

mvmt of H2O across a semi permeable mem

__**water will move from low solute conc to high solute conc**__

mangrove salinity adaptation

water has high salinity, water is going to want to flow out of the mangrove

not good for mangrove

mangrove will expend a lot of energy to inc internal conc in order to move water in

have to expel excess salt from water inside through their leaves

pH

high H= acidic

low H= alkaline

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low number= acidic

high number= alkaline

CO2 in water

H2CO3 unstable→ add H

H added which makes pH dec (more acidic) → coral bleaching

O2 in water

higher temps= less O2

deeper= less O2

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shallow cold water holds O2 better than shallow warm water

deeper water holds onto O2 better, but far from surface where O2 is

countercurrent circulation

adaptation to O2

mvmt of 2 fluids in opp directions on either side of a barrier thorugh which heat or dissolved subs (O2) are exchanged

thermoregulation

the ability of an org to control the temp of its body

cold temps:

• fat/blubber

• high metabolism→ generates heat

• countercurrent circulation

glycerol prevents hydrogen bonds from coming together to freeze

glycoproteins- lower freezing temp of water→ allow fish to be frozen solid but cells are not perforated so fish lives

→ supercooling- a process in which glycoproteins in the blood impede ice formation by coating any ice crystals that begin to form

thermal optimum- range of temps within orgs perform best

liebigs law of the minimum

if one of the essential plant nutrients is deficient, plant growth will be poor, even if all the other essential nutrients are abundant

essential nutrients of plants

O2

C

H

N

P

Ca

K

water potential

a measure of water’s potential energy which indicates its tendency to move from one area to another

gravity- high grav=more likely to move

pressure- high pressure= more likely to move

osmotic potential- higher OP= more likely to move

matric potential - higher MP= more likely to move

matric potential

the potential energy generated by the attractive forces btwn water molecules and soil particles

electrical charges

field capacity

the max amt of water held by soil particles against the force of gravity

wilting point

the water potential at which most plants can no longer retrieve water from the soil

soil texture and water intake

silt= larger gaps= less SA= water flows through= oxygenated

clay= no gaps= more SA= water retained= deoxygenated

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less gaps= more SA= more water retained

cohesion tension theory

mechanism of h2o mvmt from roots to leaves due to __**water cohesion and water tension**__

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gradient differential pulls H2o into roots

tension pulls H2O up in xylem

tension cont to pull h2O up through leaf veins and water diffused out of the stoma

how does water move in dry or saline soil?

lower water potential of roots → build up of nutrients

nutrients will build up internal concentration which will bring in h2o from soil ( water from low sol to high sol)

C3 plants

most common, most efficient in wet, cool climates

photosynthesis occurs normally

C4 plants

plant shielded from O2 buildup

Co2 moved to bundle sheath cells

stoma closed, buildup of CO2

do best in hot sunny climates

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CAM plants

changes timing of photosynthesis

assimilation of CO2 happens at night

allows plant to grow in dry environments

terrestrial plant adaptations to temperature

improve water intake and retention

• long roots search for more water vs horizontal shallow roots vs horizontal roots that collect water immediatly when it rains

reduce transpiration

• leaves with spikes/hairs retain moisture better

• thick waxy leaves hold onto water better

reduce buildup of heat in tissue

kangaroo rat adaptations - water and salt

live in deserts- water is scarce

rats never drink water!

urinate crystals

nose has folds- so much SA that the water vapor in breath condensates in nose and they swallow it

\- get all the water from their food

extremely long loop of henley- where water gets reabsorbed in kidneys-> longer the loop, the more water reabsorbed

homeotherm

can maintain constant body temp

endotherm

use metabolic heat to raise body temp

poikilotherm

no constant body temp

do not have constant body temp, do not have as narrow of a range as homeotherms

ectotherm

body temp determined by environment

heterotherm

-sometimes constant, sometimes rely on environment

ex: bat

radiation

emission of EM energy by a surface

conduction

the transfer of the kinetic energy of heat btwn substances that are __**in contact**__ with one another

convection

transfer of heat by mvmt of __**liquids and gases**__

evaporation

the transformation of water from liquid to a gaseous state w input of heat energy

acclimation

an environmentally induced change in an individuals physiology

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goldfish exp:

goldfish at 5 deg C, others at 25 deg C

goldfish at 5 deg had cold water isozymes

goldfish at 25 had warm water isozyme

when raced, 5 deg goldfish performed better

in cold water conditions and 25 deg

performed best at warmer temps

SA to vol ratio

SA inc by 2

vol inc by 3

colder you are the less surface area you want and more volume

• if you are in the tundra, you do not want a lot of skin showing, but you want a lot of puffy coats

the warmer you are the more SA you want and less volume

• in the desert, you want more skin showing(shorts) and no puffy coats

blood shunting

we can close precap sphincters, cutting off circulation

to extremeties in favor of keeping organs warm

microhabitat

a specific location within a habitat that typically differs in environmental conditions from other parts of the habitat

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migration

seasonal mvmt of animals from one area to another

dormancy

a condition in which orgs dramatically reduce their metabolic processes

diapause

hibernation

torpor

aestivation

diapause

insects

dormancy in period of unfavorable environmental conditions

hibernation

mammals

reduce the energetic costs of being active by lowering their heart rate and dec their body temp

torpor

birds and mammals

brief period of dormancy where individuals reduce their activity and body temp

aestivation

summer

the shutting down of metabolic processes during the summer in response to hot or dry conditions

life history

schedule of an orgs growth, development, reproduction, and survival

can look at age and size at maturity, number and size of offspring, and lifespan/reproductive investment

fecundity

the number of offspring produced by an org per reproductive episode

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every time i give birth, how many offspring come of it?

parity

the number of reproductive episodes that an org experiences

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how many times do you give birth?

parental investment

the amt of time and energy given to an offspring by its parents

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do i take care of you?

longevity

the life span of an org, also known as life expectancy

variation in life history

how orgs allocate energy to growth, survival and reproduction

variation within species in how orgs allocate energy-

genetic reasons- certain amt of offspring at a time

environmental reasons- if enviornmental conditions favorable, then more energy allocated to growth

mix of both

what are the life history categories?

r selection and K selection

r selection

high rates of pop growth, reproduce fast

die at young age, energy invested in amt of offspring

early maturation, low parental investment

mice, weedy plants

k selection

slow rates of pop growth

long lived, develop slowly

late maturation

invest heavily in each offspring

large mammals

the r selection and k selection are on a ……

continuum.

multiple orgs fall in between these categories

stress tolerators plants

grow in non ideal conditions (low pH, high solute, dry soil)

cannot allocate energy towards growing fast, growth is slow

sexual maturity is late, not many seeds

__**HIGH asexual reproduction**__

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