![Page 1: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/1.jpg)
Energy and Living Things
![Page 2: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/2.jpg)
Outline• Energy Sources• Solar-Powered Biosphere• Photosynthetic Pathways• Using Organic Molecules• Chemical Composition and Nutrient
Requirements• Using Inorganic Molecules• Energy Limitation• Food Density and Animal Functional
Response• Optimal Foraging Theory
![Page 3: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/3.jpg)
Energy Flows Through Living Systems
Plants= Autotrophs
Heterotrophs
![Page 4: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/4.jpg)
• Autotroph: ‘self feeder’ - an organism that can gather energy (usually from light) … to store in organic molecules– Photosynthesis– chemosynthesis
• Heterotroph: An organism that must rely on other organisms to capture light energy … must rely on breakdown of organic molecules produced by an autotroph as an energy source– Classified by trophic level
![Page 5: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/5.jpg)
Photosynthesis • Capture and transfer light energy to chemical
bonds• Occurs in:
– Plants– Algae– Certain Bacteria
• Not a perfect process – some energy is lost - entropy
![Page 6: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/6.jpg)
How Photosynthesis Works• Light strikes leaf• Energy absorbed by chemical pigments• Absorbed energy drives chemical
processes to convert CO2 into larger molecules– First simple sugars – 6 carbon ring structures– Later many molecules of simple sugars joined
together to form larger molecules or converted to other compounds
– Energy absorbed in building larger molecules, released as they are broken down
![Page 7: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/7.jpg)
Only certain Wavelengths of Light are Used in Photosynthesis
• Light Energy Used = ‘Photosynthetically Active Radiation’ or PAR – How Much is absorbed: determined as photon flux
density.• Number of photons striking square meter surface each
second.
• Chlorophyll absorbs light as photons.• Landscapes, water, and organisms can all change the
amount and quality of light reaching an area.
• Light not absorbed is reflected– Some in PAR + all in green and yellow wavelengths
![Page 8: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/8.jpg)
![Page 9: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/9.jpg)
Absorption spectra of chlorophylls and carotenoids
Wavelengths most useful in driving photosynthesis
Wavelengths not used - reflected
![Page 10: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/10.jpg)
Fall color• In many
plants production of chlorophyll ceases with cooler temperatures and decreasing light
• other pigments become visible
![Page 11: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/11.jpg)
Modifications of Photosynthesis for Dry Climates
• C3 Photosynthesis
– Used by most plants and algae.
– CO2 enters leaves BUT water vapor leaves• Poorly adapted to hot dry environments
• C4/CAM photosynthesis: Modifications in biochemical processes– Increased efficiency in CO2 absorption
– Fewer stomata required/stomata only open during night decreased loss of water vapor
![Page 12: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/12.jpg)
C3 PhotosynthesisCO2 enters passively so stomata have to be open for long periods
of time
![Page 13: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/13.jpg)
Why C3 Photosynthesis Doesn’t always work out -
CO2 must enter though stomata• stomata (sing., stoma)
are tiny holes on the undersides of leaves
• CO2 enters and moisture is released
• In hot, dry climates, this moisture loss is a problem
![Page 14: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/14.jpg)
C3 grasses (yellow)
dominant in cool temperate
– C4 plants don’t compete so well there
C4 grasslands (orange) have evolved in the tropics
and warm temperate regions
![Page 15: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/15.jpg)
C4 Photosynthesis
![Page 16: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/16.jpg)
Photosynthetic Pathways
• CAM Photosynthesis– (Crassulacean Acid Metabolism)– Limited to succulent plants in arid and semi-
arid environments.• Carbon fixation takes place at night.
– Reduced water loss.
• Low rates of photosynthesis.• Extremely high rates of water use efficiency.
![Page 17: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/17.jpg)
CAM Photosynthesis
![Page 18: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/18.jpg)
• Producers • Herbivores– Animals that eat plants– The primary consumers
of ecosystems
– Green plants and algae– Use solar energy to build
energy-rich carbohydrates
• Carnivores
– Organisms that eat dead organisms
• Decomposers– Organisms that
break down organic substances
– Animals that eat herbivores– The secondary consumers of ecosystems– Omnivores are animals that eat both plants and animals– Tertiary consumers are animals that eat other carnivores
• Detritivores
![Page 19: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/19.jpg)
Efficient Breakdown of Products of Photosynthesis Requires Oxygen
• Complex series of reactions, oxygen serves as the terminal electron acceptor
• May occur in some organisms w/o oxygen (anoxic conditions)– anaerobic respiration= fermentation– Inefficient– End products vary with organism involved
• Ethanol, proprionic acid, lactic acid, etc.
![Page 20: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/20.jpg)
• Three Feeding Methods of Heterotrophs:– Herbivores: Feed on plants.– Carnivores: Feed on animal flesh.– Detritivores: Feed on non-living organic matter.
![Page 21: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/21.jpg)
Classes of Herbivores
• Grazers – leafy material
• Browsers – woody material
• Granivores – seed
• Frugivores – fruit
• Others – nectar and sap feeders– Humming birds, moths, aphids, sap suckers
…
![Page 22: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/22.jpg)
Herbivores
• Substantial nutritional chemistry problems.– Low nitrogen concentrations – difficulty
extracting needed protein/amino acids from source.
– Require 20 amino acids to make proteins ~ 14 are must come from diet
![Page 23: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/23.jpg)
How do plants respond to feeding pressures by herbivores?
• Mechanical defenses – spines• Chemical defenses
– Digestion disrupting chemicals – tannins, silica, oxalic acid
– Toxins – alkaloids• More common in tropical species
How do animals respond?– Detoxify– Excrete– Chemical conversions – use as nutrient
![Page 24: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/24.jpg)
• Digestion Schemes of Herbivores
• Require extensive digestive processing
• Rumnants – 4 part stomach– Rapid feeding,
coarse material is re-milled (regurgitated bolus) after initial fermentation
• ‘Chewing their cud’
![Page 25: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/25.jpg)
• Coprophagy: expel moist fecal material, re-ingest– 50-80% of fecal
material recycled • acts as external
rumen • bacterial activity
produces B vitamin Cecum is site of
much bacterial activity, moist fecal pellets enclosed in
protein produced
![Page 26: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/26.jpg)
Carnivores
• Predators must catch and subdue prey - size selection.– Usually eliminate more conspicuous members
of a population (less adaptive).– act as selective agents for prey species.
![Page 27: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/27.jpg)
![Page 28: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/28.jpg)
• European River Otter:• Lutra lutra• Widest ranging of
otters• Diet varies with
abundance of prey
• http://itech.pjc.edu/sctag/E_OTTER/Index.htm
![Page 29: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/29.jpg)
![Page 30: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/30.jpg)
![Page 31: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/31.jpg)
Optimal Foraging Theory
• Assures if energy supplies are limited, organisms cannot simultaneously maximize all life functions.– Must compromise between competing
demands for resources.• Principle of Allocation
• Fittest individuals survive based on ability to meet requirements principle of allocation
![Page 32: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/32.jpg)
Optimal Foraging Theory
• All other things being equal,more abundant prey yields larger energy return. Must consider energy expended during:
• Search for prey• Handling time
• Tend to maximize rate of energy intake.
• What would a starving man do at an all you can eat buffet?
![Page 33: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/33.jpg)
Optimal Foraging in Bluegill Sunfish
![Page 34: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/34.jpg)
Adaptations of Prey to being preyed upon
• Predator and prey species are engaged in a co-evolutionary race.
• Avoid being eaten – avoid starving/becoming extinct
• Defenses:– Run fast– Be toxic – and make it known– Pretend to be toxic
• Predators learn to avoid
![Page 35: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/35.jpg)
Carnivores• Consume nutritionally-rich prey.
– Cannot choose prey at will.• Prey Defenses:
– Aposomatic Coloring - Warning colors.– Mullerian mimicry: Comimicry among several species of
noxious organisms.– Batesian mimicry: Harmless species mimic noxious species.
![Page 36: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/36.jpg)
Mullerian mimicry: Comimicry
![Page 37: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/37.jpg)
Batesian mimicry: Harmless species mimic noxious species
![Page 38: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/38.jpg)
Aposomatic Coloring - Warning colors
![Page 39: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/39.jpg)
![Page 40: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/40.jpg)
Detritivores
• Consume food rich in carbon and energy, but poor in nitrogen.– Dead leaves may have half nitrogen content
of living leaves.
• Fresh detritus may still have considerable chemical defenses present.
![Page 41: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/41.jpg)
Detritivores and decomposers
![Page 42: Energy and Living Things. Outline Energy Sources Solar-Powered Biosphere Photosynthetic Pathways Using Organic Molecules Chemical Composition and Nutrient](https://reader036.vdocuments.us/reader036/viewer/2022062804/56649f0b5503460f94c1ed5c/html5/thumbnails/42.jpg)
Review• Energy Sources• Solar-Powered Biosphere• Photosynthetic Pathways• Using Organic Molecules• Chemical Composition and Nutrient Requirements• Using Inorganic Molecules• Energy Limitation• Food Density and Animal Functional Response• Optimal Foraging Theory• Adaptations