BIO 150 LEC Quiz 1 p2 Flashcards
ABIOTIC FACTORS
light, temperature, water
The ability of an organism to MAINTAIN its ECOLOGICAL NICHE is determined by its ability to tolerate a range of PHYSICAL and CHEMICAL FACTORS present in the environment.
Law of Tolerance
Law of Tolerance was coined by
Victor Ernest Shelford, 1911
Graph of Law of Tolerance
x-axis: _______
y-axis: _______
x-axis: Intensity of condition
y-axis: Performance of species: survive, grow, reproduce
- Generalized response
- Extreme conditions are ________; less extreme
conditions PREVENT _______; only OPTIMAL CONDITIONS ALLOW REPRODUCTION - Appropriate for conditions like TEMP and pH
RESPONSE CURVE 1
LETHAL ; GROWTH
- can be ZERO
- Lethal only at high intensities
- LOW-LEVEL intensity or concentration of the factor has NO
detectable EFFECT but an increase begins to cause damage and a
further increase may be lethal. - Response curve for TOXINS, radioactive emissions, CHEMICAL
pollutants
RESPONSE CURVE 2
- can NOT be ZERO
- Response to conditions that are toxic at high levels but
________, as a RESOURCE FOR GROWTH, at LOW LEVELS - This is the case for NaCl and for many elements that are
essential MICRONUTRIENTS (e.g. Cu, Zn, Mn, etc.)
RESPONSE CURVE 3
ESSENTIAL
There are always ________…
Organisms can tolerate different conditions, but their ability to survive depends on many factors, and being strong in one area often means being weak in another.
trade-offs
visible electromagnetic radiation (400-700 nm); primary energy source for the biosphere
LIGHT
Light emitted from the sun
RADIANT ENERGY
4 Characteristics of Light that influence its effects on organisms
DIP Q
DIRECTIONALITY (from what angle?)
INTENSITY (how much?)
PERIODICITY (for how long?)
QUALITY (what wavelengths?)
– Strength of light;
- measured in _____ or _____ (fc) ;
INENSITY
LUX / FOOTCANDLES
FACTORS OF LIGHT INTENSITY
- DISTANCE FROM SOURCE
- ANGLE OF INCOMING LIGHT
- ORBITAL VARIATIONS
- SOLAR ENERGY OUTPUT
- other factors (e.g. SEASON, WEATHER, CLOUD COVER, TIME OF DAY, PLANT COVER, AIR PARTICLES)
low angle = low intensity;
high angle = high intensity
ANGLE OF INCOMING LIGHT
ORBITAL VARIATIONS
PESO
- PRECESSION
- ECCENTRICITY
- variations in solar energy output (SOLAR CYCLE)
- OBLIQUITY
how elliptical the orbit is
- ECCENTRICITY
degree of tilt
- OBLIQUITY
direction of tilt
- PRECESSION
SOLAR CYCLE.
the approximately 11-year cycle of solar activity, characterized by fluctuations in the number of sunspots on the Sun’s surface (SUNSPOT MINIMUM & MAXIMUM). It was discovered by ____ _____ ______ in 1843
Samuel Heinrich Schwabe
SCHWABE CYCLE
Wavelength and color of light
QUALITY OF LIGHT
- duration of day length;
- function of latitude and season
PERIODICITY
- angle of incidence
- affected by lat, season, time of the day
- affected by the TILT & PRECISION
DIRECTIONALITY
FATE OF INCOMING SOLAR RADIATION
SR. RAT
SCATTERED
REFRACTED
REFLECTED
ABSORBED
TRANSMITTED
FATE OF INCOMING SOLAR RADIATION
in PLANTS: WITHOUT CHANGE in wavelength
REFLECTED
FATE OF INCOMING SOLAR RADIATION
in PLANTS: ABSORBED - _____, ______, ______
- RAISE plant TEMPERATURE.
- contribute to TRANSPIRATION / evaporation
- drive PHOTOSYNTHESIS / reach chloroplast
FATE OF INCOMING SOLAR RADIATION
in PLANTS: after some wavelengths have been filtered out; CHANGE in both QUALITY and INTENSITY of light)
TRANSMITTED
FILTRATION OF LIGHT IN A:
- 79% absorbed by the canopy layer
- 2% absorbed by the forest floor
TROPIC RAINFOREST
FILTRATION OF LIGHT IN A:
- 36% absorbed by the grass
- 5% absorbed by the soil
- an OPEN AREA has more SURFACE AREA for light to be ABSORBED
GRASSLAND
LIGHT AS AN ENVIRONMENTAL FACTOR
- as a CONDITION
- as a RESOURCE
LIGHT AS AN ENVIRONMENTAL FACTOR
– involved in:
* Circadian rhythms
* photoperiodism
* phototropism
* phototaxis
- as a CONDITION
LIGHT AS AN ENVIRONMENTAL FACTOR
– involved in phototrophy, photosynthesis
- as a RESOURCE
Photosynthetically Active
Radiation
LIGHT AS AN ENVIRONMENTAL FACTOR * as a CONDITION
response to DAY LENGTH
PHOTOPERIODISM
LIGHT AS AN ENVIRONMENTAL FACTOR * as a CONDITION
growth movement
PHOTOTROPISM
LIGHT AS AN ENVIRONMENTAL FACTOR * as a CONDITION
movement follows the light as stimulus
PHOTOAXIS
LIGHT AS AN ENVIRONMENTAL FACTOR * as a CONDITION
the physical, mental, and behavioral changes an organism experiences over a 24-hour cycle
CIRCADIAN RHYTHMS
LIGHT AS AN ENVIRONMENTAL FACTOR * as a RESOURCE
utilizing energy from the sun to perform metabolic processes
PHOTOTROPHY
LIGHT AS AN ENVIRONMENTAL FACTOR * as a RESOURCE
specific process that uses light to produce glucose
PHOTOSYNTHESIS
LIGHT AS AN ENVIRONMENTAL FACTOR * as a RESOURCE
- utilizing _____ ______ ______, wavelengths which DEPEND ON PRIMARY PIGMENTS USED FOR PHOTOSYNTHESIS
- color of light = REFLECTED light spectrum
e.g. Algae absorbs blue-violet light
PHOTOSYNTHETICALLY ACTIVE RADIATION (PAR)
SHADE is a ____ ____ ____ because shading REDUCES the INTENSITY of light and changes which particular wavelengths are transmitted across
RESOURCE DEPLETION ZONE (RDZ)
Zone that light does not reach
APHOTIC ZONE
Zone that light reach
up until ____meters in open ocean
PHOTIC ZONE
200m
ORGANISMS THAT UTIIZE LIGHT; NOT ALL PHOTOSYNTHESIZES
PHOTOAUTOTROPHS
Types of PLANTS based on LIGHT UTILIZATION
HELIOPHYTES
SCIOPHYTES
HELIOPHYTES
(a.k.a. _____ ______)
▪ needs ____ ____ for growth
▪ efficient use of _____ LIGHT INTENSITY
▪ never reach PHOTOSYNTHETIC ______
▪ SMALL, ANGLED leaves
SUN PLANTS
FULL SUN
HIGH
SATURATION
SCIOPHYTES
(a.k.a. ___ _____)
▪ Inhibited _____ full sun
▪ More efficient Ps at ____ LIGHT INTENSITIES
▪ often reach SATURATION LEVELS at _____ full sunlight
▪ LARGE, HORIZONTALLY oriented leaves w/ lots of ______ and _____ ____
SHADE PLANTS
UNDER
LOW
20%
CHLOROPHYLL ; ACESSORY PIGMENTS
Point of MINIMUM AMOUNT of LIGHT TOLERANCE for photosynthesis
LIGHT COMPENSATION
Point of MAXIMUM AMOUNT of LIGHT TOLERANCE for photosynthesis
LIGHT SATURATION
- a measure of the AVERAGE KINETIC ENERGY of the atoms or molecules in the system
TEMPERATURE
- thermal energy transferred from a HOTTER SYSTEM to a COOLER SYSTEM;
- 0 HEAT FLOW if in _____ ______
HEAT
THERMAL EQUILIBRIUM
TEMPERATURE IS USED TO DESCRIBE:
- MICROCLIMATE
- MACROCLIMATE
what WEATHER STATIONS and what we represent with CLIMATE DIAGRAMS
MACROCLIMATE
climatic variation on a scale of a few km, m, cm; measured over SHORT PERIODS OF TIME
MICROCLIMATE
TEMPERATURE IS AFFECTED BY:
- ALTITUDE & LATITUDE
- CONTINENTAL/MARITIME LOCATION
- SURFACE FEATURES (Vegetation)
Organisms respond to TEMPERATURE like the RESPONSE CURVE ____ of Shelford’s Law of Tolerance
RESPONSE CURVE 1
4 TYPES OF MICROORGANISMS THAT THRIVE IN CERTAIN TEMPERATURES:
HYPERTHERMOPHILES
THERMOPHILES
MESOPHILES
PSYCHROPHILES
MICROORGANISMS THAT Thrive at very high temp (above 100°C)
HYPERTHERMOPHILES
MICROORGANISMS THAT live at high temp (60-100°C)
THERMOPHILES
MICROORGANISMS THAT live at moderate temp (20°C)
MESOPHILES
MICROORGANISMS THAT live at low temp (-20°C)
PSYCHROPHILES
Types of organisms based on…
- STABILITY OF BODY TEMP
- SOURCE OF ENERGY FOR REGULATING BODY TEMP
Types of organisms based on… * STABILITY OF BODY TEMP
COLD BLOODED ; THERMOCONFORMERS
“______” = VARYING
POIKILOTHERM
“POIKILO”
Types of organisms based on… * STABILITY OF BODY TEMP
WARM BLOODED = THERMOREGULATORS
“______” = SAME
HOMEOTHERM
“HOMEO”
Types of organisms based on… * SOURCE OF ENERGY FOR REGULATING BODY TEMP
ECTOTHERM
ENDOTHERM
Types of organisms based on… * SOURCE OF ENERGY FOR REGULATING BODY TEMP
heat from outside (environment)
ECTOTHERM
Types of organisms based on… * SOURCE OF ENERGY FOR REGULATING BODY TEMP
heat from inside (organism’s own
metabolism)
ENDOTHERM
T OR F.
Many poikilotherms are ectotherms : many homeotherms are endothermic,
BUT some animals that exhibit _______ endothermy are pokilothermic
TRUE
FACULTATIVE
Endotherms and ectotherms CO-EXIST:
HIGH COST: HIGH BENEFIT strategy of _______;
LOW COST: LOW BENEFIT strategy of _______
HIGH:HIGH = ENDOTHERMS
LOW:LOW = ECTOTHERMS
Some adaptations to extreme temperatures
- Temperature Regulation Mechanisms
- Cold Adaptations
- Heat Adaptations
Some adaptations to extreme temperatures
TEMPERATURE REGULATION MECHANISM
- INSULATION (e.g. blubbers)
- EVAPORATIVE COOLING (e.g.
panting, sweating) - Adjustment of SUPERCOOLING POINTS
- COUNTERCURRENT HEAT EXCHANGERS (e.g. blood
vessels in bird’s feet)
Some adaptations to extreme temperatures
COLD ADAPTATIONS
- FREEZE-AVOIDANCE (ice crystals are prevented from forming)
- FREEZE-TOLERANCE (encourage formation of extracellular ice to minimize intracellular damage)
- Other morphological, anatomical, and behavioral features
Some adaptations to extreme temperatures
HEAT ADAPTATIONS
To high temp.
– MODIFIED MEMBRANES and
PROTEINS
– PROTECTIVE LAYERS (waxes)
– REFLECTVE SURFACES
– Other anatomical features
RESTING STAGES under extreme temperatures:
THE
- TORPOR
- HIBERNATION
- ESTIVATION
RESTING STAGES under extreme temperatures:
state of low metabolic rate (hrs)
TORPOR
RESTING STAGES under extreme temperatures:
prolonged ‘stasis’ (months) during winter
HIBERNATION
RESTING STAGES under extreme temperatures:
prolonged ‘stasis’ during summer
ESTIVATION
Temperature as a STIMULUS/SIGNAL FOR:
- Whether or not an organism starts _______ (e.g. germination)
- May _______ with other STIMULI (e.g. photoperiod)
- Growth, FLOWERING, GERMINATION, RIPENING of fruits Interaction of temperature with other factors
- conditions may favor growth and/or spread of _______ AGENT, or WEAKENING OF HOST
DEVELOPMENT/GROWING
INTERAC T
DISEASE
DEFENSES OF TEMPERATURE
- COMPETITION
- HUMIDITY
DEFENSES OF TEMPERATURE.
– modifies the response to temp because of the presence of a competitor
COMPETITION
DEFENSES OF TEMPERATURE.
– RH closely tied to Temp
HUMIDITY
