Exam 2 Flashcards
What are animals uses for toxins?
Mainly to capture prey
(Some for defense)
Ex. Wasps, snakes, spiders, scorpions, lizards, jellyfish
What are plants uses for toxins?
-Mainly for defense
(Some for offense)
-Plants exhibit widest diversity of chemicals
-Provide richest source for human uses
Why use Venom?
- Circumvent prey defense systems
- Take larger prey down
- Take extremely mobile prey down (Paralysis)
Neurotoxins
- Interacts with nerve cells
1. Affects sodium and potassium channels
i. Channels open with nerve impulse
ii. Nerve impulse is movement of NA+/K+
- OR Causes release of neurotransmitters
Cytotoxins
- Destroys many different cell types
- Results in swelling, internal bleeding, lesions
Evolution of Plant Toxins
-Plants use chemicals mainly for defense
Ex. Hogweed- Heracleum and Furocoumarins
- Kids use it as telescope for fun
- Chemicals + Sunlight = Swelling
Plant Toxic Strategies
- Feeding deterrants
- Digestibility reduces
- Truly toxic
Feeding Deterrants
- Tastes Bad
- Capsicum
- Burning taste of peppers
- Produced in the septa odorless, colorless, crystalline-waxy compound hydrophobic
Digestibility reduces
Extra filing with no nutrients
Bind to nutrients in herbivores gut
Truly toxic
- Attempts to kill herbivore
- Fast acting chemicals on physiology
Responses to heat
- Heat destroys cells, releases H+ and lipid byproducts
- Heat can also directly open receptor channel
- Birds lack receptor to heat so they don’t have any ill effects on fruit
Tannins
- Interferes with protein function and absorption
- Saliva Enzyme > Plant Protein > Enzyme Intact > Protein broken up
- Plants taste bad
Nicotine Induced Defense
- Plants has some reserves in roots
- Feeding by insects produce signal of attack
- Nicotine mobilized and up-regulated
- May take several hours - Insect ingests nicotine
What does Nicotine mimic?
Acetylcholine
Examples of human uses for toxins?
- Taxol
- Digitalis
- Caffeine
- High blood pressure
Taxol
- Bark from Pacific Yew Tree
- Anti-cancer drug
High blood pressure
- Venom from Brazilian Pit viper
- Blood pressure drops
Plant Latex
- Milky sap that gels when exposed to air
1. Seals wounds on plant
2. Deter Herbivores
3. Stores food
Vulcanization
- Heating of rubber and sulfur to strengthen rubber
- Rubber becomes harder, less sticky, and resistant to chemical attacks
What makes Earth unique?
Sun energy
Abundant of water
Photosynthesis
Sunlight, CO2, Water, Glucose
-Makes Oxygen
Light vs Dark Reaction
Light
-Conversion of light energy into chemical energy
Dark
-Incorporation of Carbon into sugar
Chloroplast
- Organelle where photosynthesis occurs
- Can have hundreds per cell
Parts of Chloroplast
- Outer Membrane
- Stroma
- Grana
- Thylakoid
Outer Membrane
Surrounds chloroplast
Stroma
- Liquid within chloroplast
- Dark Reaction
Grana
Stack of thylakoids
Thylakoid
- Pigment containing units
- Light Reaction center
- Photosystems
Photosystems
- Assembly of 250-400 pigment molecules
1. Antenna complex - Directs photon to reaction center
2. Reaction center - Uses photon
3. Pigments absorb light - Energy may be dissipated as heat
- May be re-emitted (Fluorescence)
- Energy may be captured in chemical bond
Chlorophyll
The Lollipop
- Ring
- Site of photon absorption - Tail
- Attaches to membrane
Chlorophyll Reaction Center
- Protein complex at center of photosystem
- Light energy liberates electrons
- Electrons captured and used for work
Photosystems in plants
Photosystem II
- Absorbs light at 680 nanometers
- Supplies electrons for photosystem I
Photosystem I
- Absorbs light at 700 nanometers
- Supplies electrons for sugar building
How do photosystems recharge?
- PS II gets electrons from water
- H+ atoms forms ATP (energy)
Photosynthesis wrap-up
- Capture Light energy
- Splitting of water into O+ and H+
- Production of ATP molecules
Solar Power Types
- Photovoltaics
- Sunlight > Energy - Solar Thermal
- Sunlight > Heat - Passive Solar
- Heating through architectural design
Photovoltaic cell
- Sunlight > Energy
1. N-Type Layer of Silicon - Phosphorus atoms added
2. P-Type Layer of Silicon - Boron atoms added
Problems with Photovoltaic
- Energy gap problem
- only small part of light spectrum is used
- Multi-Junction cells
- Stack of cells with different semiconductors - Absorbing and concentrating light
- Glass coated with organic dye
Solar Thermal
- Sunlight > Heat
1. Water usually used as medium for heat storage
2. Mostly used for residential heating
3. Steam generation applications being tested
Solar Thermal Example
- Direct system
- Active indirect system
- Flat Plate Collector
- Solar Evacuated tubes
- Solar Power Plants
- Passive Solar
- Capturing Light
- Direct System
- Active Indirect system
- Flat Plate Collector
- Solar Evacuated tubes
- Batch collector passive system
- Used in winter
- Closed loop, freeze-protection system - Shower for camping/hiking
- Vacuum between outer and inner tube
- Like Hydro-flask
- Solar Power Plants
- Passive Solar
- Capturing Light
- Mirrors are used to concentrate sunlight
- Bunch of mirrors focus on one point
- Produce steam to drive electric generator - Heating through architectural
- Design building to control amount of sunlight coming in or out
- Solar Powered House - DyeSol
- Biomimetic Pigment
Photolysis of Water
- PS II Substructure
- Magnesium atoms as catalyst to break down water
Electron Release
- Photosystems release electrons for transfer
- If they can be directed to certain areas, they can be used in chemical reactions
- Photozyme
Photozyme
- Based on antenna proteins in bacteria/plants
- Goal to make linear chain to transfer photons
- Pioneered by James Guillet
Oil Spill?
• Photozymes could convert oil to non-toxic compounds
• Cleans up contaminants
Proton Power
- Develop artificial cells to power chemical reactions
- Take these components, embed in membrane
- Add building blocks and light
Pollutants from Oil
- Heating Oil
- 15-20 carbons per chain - Diesel
- 10-15 carbons per chain - Gasoline
- 5-10 carbons per chain
- Mostly octane
Octane
- Octane handles compression well
2. Increasing compression adds more power
Burning of Fuel. Complete burning?
No.
- Carbon monoxide
- Nitrogen oxides
- Some Sulfur Oxides
- Hydrocarbons
- GETS INTO OZONE
Biofuels
Carbon-based fuel produced from renewable resources
Sources of biofuel
Anything renewable
- Corn
- Wood
- Palm Tree Oil
- Sugar Cane
- Algae
Bioethanol Production
- Produce ethanol from sugars and starches
- Yeast ferments sugar and produces ethanol (Anaerobic Respiration)
Ethanol Production (from plant material to ethanol)
- Cut and mill plant material
- Treat milled material with enzymes (Breakdown complex sugars and starches)
- Add yeast and water to ferment
- Distill Ethanol
- Dehydrate (concentrate ethanol)
Homemade Biodiesel
- Obtain Vegetable Oil
- Mix with methanol and Lye
- Heat
- Allow to settle
- Get rid of glycerin
- Filter
Is using straight vegetable oil okay?
Yes
- High viscosity (Resistance to flow)
- Breakdowns in air quicker than biodiesel
- High gelling point
Hydrogen fuel
- H2 + O2 > Energy + water
- Hydrogen tank and membrane
- Only problem is having enough H2
What to use as catalyst for hydrogen fuel?
- Catalyst facilitates Hydrogen and Oxygen reaction
2. Platinum is currently the catalyst of choice
Where to get Hydrogen source?
-Convert to natural gas OR
-Electrically split gas
REQUIRES LOTS OF ENERGY EITHER WAY
Who lives in a termite society?
- King
- Queen
- Soldier
- Worker
- Winged Reproductive
King Termite
- Sole reproducing male
- Rarely leaves queen
- Pair may live for 20 years
Queen Termite
- Female Reproductive
- Abdomen is filled with egg producing organs
- Determines what eggs will develop into
- Keeps offspring sterile through secretions of hormones
Soldier Termite
- Male and female
- Defends nest
- Some have poisons
Worker Termite
- Blind males and females (uses smell)
- Takes care of Queen and King and rear eggs
- Constructs nest
- Feeds colony through secretions
Winged Reproductive
- Male and female
- Both swarm out of nest
- Female lands on ground and attracts male
- Pair discard wings and burrow into ground
- Digs chamber and mates
Caste System
Termites
-Physically distinct individual with specific function
Termite Evolution
- One-piece nest
- Piece of wood - Intermediate nest
- Piece of wood
- Tunnels to forage - Separate nest
- Nest used for rearing and shelter
- Workers forage in open
Termite Nest Formation
- Nest starts as simple chamber by pair
- Expands as workers become available
- Nest material constructed by:
- Soil, wood, fecal matter
- Saliva is used as glue
Why construct a nest?
- Termites are prone to dehydration
- Need to control humidity
- Barrier to water
Climate inside termite nest?
- Humid
- Hot, dry
- More CO2 and O2
Solutions to colony growth?
- Make bigger nest
- add ventilation
Climate regulation using ventilation?
- Cool air flows down peripheral (side) shafts
2. Heated air rises up central shaft
Judith Korb and Eduard Linsemar
- Sunlight heats mound
- Air in peripheral tubes heat
- Air rises and pulls air from nest
- CO2 and O2 mix
- Water vapor condense into tubes
- At night, heat causes upward flow in central shaft only
Termite Mound Summary
- Size of mound determines colony size
- Termites need high humidity, stable temperature, and gas exchange in nest
- Nest designs that did all 3 favored evolutionarily
- Advances in nest design allowed larger colonies
- Larger colonies better at surviving and competing
East Gate Centre
- Based on Termite
- Atrium in center
- Chimneys and Intake Ports
- Cool air goes into Intake Ports
- Hot air rises out of Chimneys
Today Examples of Termite Buildings
Mich Pearce
CH2 Building
What does it take to fly?
- Lift to overcome Gravity
- Thrust to overcome Drag
Lift and Thrust
Airfoil Wing
- Airplane wing
- Air that travels over wing moves FASTER with less pressure
- Air that travels under wing moves SLOWER and pushes UP
What does it take to maneuver?
- Yaw (side to side)
- Pitch (Up and down)
- Roll (Tilting of wings)
How have birds adapted flight?
- Primary Feathers (power)
- Secondary Feathers (Lift)
- Covert Feathers (Shape)
How do birds control yaw without a rudder?
Flexibility of wings and tail
Downstroke vs. Upstroke
- Downstroke
- Feathers press together to make firm surface - Increase air pressure and generate lift
Upstroke
1. Feathers separate to reduce resistance
Flapping
- Primaries move the forward and create cup of air to increase air pressure
- Secondaries move very little
Types of wings
- Slotted High Left
- High Speed
- High Aspect Ratio
- Elliptical
Slotted High Left
Wide wing
Deeply curved
Primaries are airfoils
Ex. Eagle, stork, buzzard
High Speed
Forms one airfoil
Less curvature
Primaries not slotted
Ex. Duck, Falcon
High Aspect Ratio
Like High Speed
Much Longer
Greater Lift
Ex. Gull, Albatross
Elliptical
Most Common
High maneuverability
Relatively slow
Ex. Crow, Pigeon
Bird Flight Muscles
- Muscles attack to wing bone and keel
- Large muscle pulls down
- Small muscle pulls up
- Bones fused for support
- Wing, Keel, Scapula
How have insects adapted flight?
• Insects can hover and fly backwards • More maneuverability • Have two pairs of wings -Forewing -Hindwing -Can lock together during flight
Insect Wings
- Veins (Stiffen wing)
- Cells (Contain wing material)
- Wings are NOT shaped like airfoil
How do insects generate lift?
- Moved down and forward
- Wings flipped leading edge toward rear
- Moved up and backward
- Wings flip up again
Insect flight muscles
• Most insects use “indirect flight” muscles • Wings attach to “shell” of thorax • Muscles contract shell and wings beat -Wings go up (Muscle pulls down) -Wings go down (Muscles pull in)
Helicopter Architecture
- Swash Plate
- Elevator
- Rotor Engine
- Tail Fin
- Tail Rotor
Helicopter Controls
- Cyclic Stick
- Climb or descend uneven tilt on rotors - Collective Lever
- Controls tilt of swash plate (both rotor blades) - Tail Rotor Pedals
- Corrects torque by changing tail rotor
Types of Human flying machines
- Small wing area, lots of thrust (Jetpack)
2. Large wing area, little thrust (Gyrocopter, Ultralight plane)
Future Directions of flight
- Micro air vehicles (MAVs)
- less than 6 in - Nano air vehicles (NAVs)
- less than 3 in
Entomopter
- Chemical muscle adaptor
- use chemical reaction to drive wing beating
- Makes no need for heavy battery
Castor Bean
Extra Credit
Seeds are toxic if chewed (Ricin)
1 milligram can kill an adult
Naked Mole Rat
Extra Credit
Lives in colonies with queen and king
Forages underground like termites but eats roots and tubers
Pangolin
Mammal evolved with scales
Uses long tongue to feed on ants and termite nests
Stalk-Eyed Fly
Extra Credit
Eyes widely separated on head
Males compete by measuring distance between eyes
Ocean Sunfish
Extra Credit
Heaviest bony fish in the world (2000 lbs)
Single female can produce 300 million eggs