Biology Unit 3 Sonoran Desert Study Set

2 ways that organisms respond to climate change

migration or death

climate envelopes

set of environmental/climatic conditions that an organism requires in order to survive

direction that species are expected to migrate

poleward and upward

upward definition

along a mountain/elevation

poleward

toward the north pole

for every 1 degree C increase in avg temp, species must shift (in meters, both poleward and upward)

175m upward

103-145m poleward

forest migration speed

exceeding slowly

assisted migration

move plans/animals to places where we think they will be able to survive the future to speed up migration

species that humans have assisted in migration (examples)

penguins, trees used in forestry

phenology (in seasons)

timing of seasonal changes in plants and animals

phenological mismatch

when the timing of events for interacting species no longer co-occurs

2 options for if species can’t migrate fast enough

adapt or die

species most likely to adapt fast enough when…

migration is slow and population is genetically diverse

abiotic characteristics in southwestern US and mexico

summer is way too hot for plants to survive, spring is too dry, winter is cool enough and has enough rainfall

van Helmonts experiment determined

that plants got C from the air, not the soil

reasons why water is important to plants

necessary for photosynthesis and structure

turgor pressure

created when vacuole, full of water, exercise outward pressure on a cell wall

plants stand up due to

turgor pressure and osmosis

osmosis

diffusion of water

passive movement of molecule from high to low conc of water to establish equilibrium

plant goes from wilted to full or

turgid (high turgor pressure)

vascular tissue (2 types)

xylem and phloem

xylem

carries water through hollow, “dead” cells from roots to leaves only in one direction

xylem carries water through… transport

passive

passive water transport using xylem through

cohesion and adhesion

cohesion

water sticks to other water molecules

adhesion

water sticks to other molecules

water escapes plant through

stomata on the bottom of a leaf

oxygen leaves plant

as stomata open, leaving with water

CO2/O2 gas exchange is a (process)

physical process

open guard cells when

water is abundant (guard cells turgid)

closed guard cells when

water is scarce (guard cells flaccid)

total amount of water transpired reliant on

amount of time stomata are open and rate

factors that impact transpiration from an open stomata

temperature, wind, humidity, surface area

2 strategies for plant survival in desert

high RGR or high WUE

RGR stands for

relative growth rate

relative growth rate

biomass gained/time

WUE stands for

water-use-efficiency

water-use-efficiency

carbon gained (growth)/water lost

High WUE

conserves water

low WUE

lose water quickly

high RGR

lots of leaves (more water loss)

chloroplasts

capture light and performs photosynthesis

photosynthesis

creates glucose (chemical energy) to ATP (chemical energy)

photosynthesis equation

H2O + CO2 + light → O2 + glucose

diffusion

flowing from high to low conc

potential energy of atoms

close e- are to nucleus, more stable, less PE

more reduced

more potential energy

reduction comes from

gaining H, adding e-, losing O

oxidized comes from

loses e-, loses H, adding O

endosymbiosis

origin story of chloroplasts

origin of chloroplasts

used to be free-living cyanobacteria

two parts of chloroplast structure

stroma and thylakoids

where does light-dependent reactions take place?

thylakoids

parts of a thylakoid

outer membrane and lumen

where are light-absorbing pigments

thylakoid membrane

where do light-independent parts of photosynthesis take place?

stroma

what do light reactions convert energy into?

light energy converts into chemical energy

light reaction equation

H2O + light → O2 + ATP + NADH

Calvin cycle product

glucose

calvin cycle reaction

CO2 → glucose + ADP + NADP+

process of light reactions (parts of light reaction)

photosystem II, ETC, photosystem I, ATP synthase

photosystem II purpose

convert light energy into excited e- on chlorophyll

where does chlorophyll+ get the extra e- during photosystem II

H2O

products of chlorophyll+ + H2O

chlorophyll, O2, 2H+

ETC purpose

pump H+ into lumen through H+ gradient (pump)

chlorophyll is ____ when reacting with water

oxidized

H+ pump pumps from ___ to ____ conc

low to high conc (against the gradient)

photosystem I purpose

convert NADP+ to NADPH

photosystem I requires

light and NADP+

ATP synthase is

an enzyme spanning the thylakoid membrane

ATP energy transformation (including where energy comes from)

converting PE in the form of a gradient into KE into chemical energy

ATP synthase purpose

converts ADP to ATP for use in calvin cycle

ADP meaning

adenosine diphosphate

ATP meaning

adenosine triphosphate

calvin cycle process

turn CO2 into glucose using chemical energy

where does calvin cycle take place

stroma

3 sections of calvin cycle

fixation, reduction, regeneration

fixation

CO2 into organic C using RuBisCO enzyme

2 problems with photosynthesis

to get CO2, plants need gas exchange

photorespiration

photorespiration

oxygen taking place of CO2 in calvin cycle, essentially wasting energy to reverse calvin cycle

when does photorespiration occur?

too hot (usually dry) or not enough CO2

2 ways plants have evolved to avoid photorespiration

C4 and CAM

C4

instead of fixing CO2 into a 3C sugar, first fixes CO2 into a 4C sugar, malate

Malate

4C sugar CO2 is fixed into to avoid photorespiration

4C prevents

oxygen from reaching calvin cycle by storing CO2 as malate

CAM photosynthesis ideal for plants that live in

both hot and dry conditions

CAM photosynthesis essentially

only opens stomata at night to limit water loss

CAM photosynthesis during the day

malate converted back into CO2 for calvin cycle to use

CAM photosynthesis division of C-fixation by

temporally (day vs night)

CAM photosynthesis effects

slow growth since not very efficient

biodiversity includes measures of…

abundance and number of species

Simpson’s Diversity Index

measure of biodiversity in regards to distribution and diversity

S’ is high when…

richness and evenness are high

S’ is low when

richness is low and/or when a few species dominate landscape

competition is strongest when…

species use resources similarly

competitive exclusion principle

no species can utilize exact same set of resource at the same time

weaker competitor will… if resources overlap (competitive exclusion)

cede overlapping resources, which shrinks niche space, by either restricting number of resource or by evolving

die

resource shared idea is called

coexistence/niche partitioning

niche

environmental conditions and resources necessary for survival and reproduction