Virus
Ubiquitous, infecting all taxonomic groups
Rhinovirus
Common Cold
Epstein-Barr Virus
Mono
Bacteriophages
Bacteria that infects bacteria cells (can be used as cloning vectors)
T2 phage infects ______
E. Coli
Tobacco mosaic virus (TMV)
The first virus ever discovered (infects wide range of plants)
Spike proteins
Glycoprotein that connects membrane to capsid (involved in binding to host cells)
Each virus species has a _______
Host range
Tissue tropism
Refers to range of tissue types a virus can infect
Lytic vs. Lysogenic cycle
Lyt- cycle ends when the host cell burst Lyso-reproduces with the host genome
Papillomavirus DNA Genome
• Infects 80% of adults • Can cause cancer of cervix, penis, throat and anus (STD) • Highly contagious • Gardasail only effective before exposure • By age 11-12 • Protects against 4 strains, including HPV-16 • Narrow tropism
Prions
• Infectious agent with no nucleic acid (infectious protein) • Comes from preexisting cell • Mad cow disease, scrapies, brain disease in sheep, and kuru • Abnormal form of normally occurring brain cell protein PrpC • Binds with normal form of protein and alters conformation • Forms harmful aggregates killing cell • Tissue deterioration and dementia
Geology
The broadest Earth science
Earth
3/4 covered by water
Earth's Layers- Crust
• Surface layer • Thin and brittle • Rocks rich in silicon and oxygen • Continental crust (usually light in color) • Granitic rock • Deep roots -actually floats in mantle • Oceanic crust (usually dark/denser in color) • Fined-grained basalt • Higher proportion of iron and magnesium • Reverse mass • Ancient sea creatures embedded in basaltic rock high in the mountains
Isostasy
Vertical positioning of Earth's crust, due to flotation in the mantle
Earth's Layers- Mantle
• Thick layer of hot rock (thickest layer) • 82% of Earth mass and 65% of volume • 2,900 km thick • Silicon and oxygen, proportionally more magnesium, iron, and calcium • Much denser than crust; pressure increases density (squeezed together because of the crust)
Earth's Layer's- Core
• Huge ball of hot metal • Mostly iron with some nickel • Radius 3,500 km • Most knowledge comes from seismology
Earth's Five Functional Layers (Outer to Inner)
Lithosphere Asthenosphere Lower Mantle Outer Core Inner Core
Lithosphere
• Shell of cool, rigid rock (where we walk) • Crust and upper mantle • 100 km thick • Thickest below continent • Broken into interlocking pieces • Tectonic plates-ride on the upper mantle
Asthenosphere and Lower Mantle
• Asthenosphere: • Under lithosphere • Mantle rock • Soft and flows VERY slowly (plastic)- not hard rock • Lower Mantle: • Below Astheno. • Strong, rigid mantle rock • Not as plastic (not plastic)
Outer and Inner Core
• Outer Core: • Hot, liquid metal (mostly iron w/ some nickel) • Spins as Earth rotates (also convection) • Creates magnetic field around earth • Geomagnetic field shields us from solar wind • High-energy particle coming from the sun • Inner Core- absolute center of the earth • Solid sphere of hot metal • Mostly iron • 7,000*C • Pressure keeps from melting
Continental Drift
World's Continents move slowly over Earth's surface
Pangaea
First super continent
Seafloor Spreading
Where the ocean floor opens -new lithosphere is created at midocean ridge -oceanic plate that will subduct under the tectonic plate and will melt
Divergent Boundaries
Neighboring plates move away from each other -Example: East African Rift Zone
Convergent Boundaries
Plates come together in slow motion collision
Three types of convergence
1)oceanic-oceanic 2)oceanic-continental 3)continental-continental
Oceanic-oceanic
-older plate subducts -ocean trench -island arcs parallel trenches -earthquakes
oceanic-continental
-basaltic oceanic plate subducts beneath continental -deep trench forms offshore -magma forms at subduction zone and erupts as lava -volcanic mountain chain
Continental-continental
-neither sink below the other -pushes one another upward -example: Himalayas -India rammed into Asia 50 million years ago
Faults
Crack that divides into two blocks of rock that have moved relative to each other
What % of Earth's surface is covered by salt water?
71%
7 Continents
Africa, Australia, North America, South America, Europe, Asia, and Antarctica
Topography
Shape of earth's surface (mountain belts, plains, plateaus, and canyons)
Continents are AROUND ______ meters ABOVE sea level
840 meters (around)
Pacific Ocean
The largest, deepest, and oldest ocean
Atlantic Ocean
The coldest and saltiest ocean
Indian Ocean
The smallest Ocean
Where is the midocean ridge?
The Atlantic Ocean
Some landforms were created by....
tectonic process
WATER (running, more powerful than the others)
wind
ice
gravity
Compression
Pushing together, converging plates
Tension
pulling apart of rock, diverging plates
Shear Stress
Slide past each other
Rocks respond to stress by
Fracture, deform elastically, and deform plastically
Fracture
Breaks under a lot of pressure
Deform elastically
Bounces back to original shape and size
Deforms plastically
Stress exceeds elastic limit
4 types of mountains
Folded, Upwarped, Fault-block, and Volcanic
Folded Mountains
• Most common type of mountain • Tallest mountain range on Earth • Tectonic collisions cause compressive stress and crumples the rock • Mountain ranges in the middle of a continent mean that plates have collide there in the past • Canadian Rockies (young) • Himalayas still converging and still growing • Appalachian Mountains (plate convergence 300 million years ago) when the African plate hit the North American plate https://www.youtube.com/watch?v=r9Uu-Gp2ztg
Upwarped Mountains
• Black Hills of South Dakota (great example) • Domelike shape, produced by compression • Single anticline • Forms when magma pushes its way up and moves crust upward • Made of older igneous and metamorphic bedrock • Sedimentary rock erodes from top
Fault-Block Mountains
• Mountain formed by tensional stress and has at least one side bounded by a normal fault • Broad uplifting over a large area • Huge blocks of crust are pushed upward along steep fault planes, while other sections drop down • Rise steeply above surrounding landscape • Teton Range and Sierra Nevada
-appears out of nowhere • https://www.coursera.org/lecture/mountains-101/2-3-types-of-mountains-q9lb3
Volcanoes
• Mountain or hill formed by the extrusion of lava, ash, and rock fragments (depending on how much pressure there is) • Conical shape • Summit has bowl-shaped depression called crater • Connected to subsurface magma chamber by a vent • Crater that exceeds 1 km is called a caldera
Caldera
When a volcano breaks
Three kinds of volcanoes
Shield, Cinder cones, and composite cones
Shield Volcano
Built by a steady supply of basaltic lava (built by oceanic crust)
Cinder Cones
Very steep, but rarely exceed 300m -built from ejected materials: ash cinder, glass, and lava fragments -single vent, pile up at steep angle
Composite Cone
High, steep sided summit and gently sloping flanks -alternating layers of lava, ash, and mud -example: Mount St. Helens
Volcanoes
• Most form near divergent or convergent plates • Ring of Fire encircles most of the Pacific Ocean • Convergent boundaries • 75% of Earth’s volcanoes • 600 are active (most are underwater)• Some are created by hot spots • Stationary, exceptionally hot region deep in Earth’s interior • Mantle rock over hotspot softens and is moved upward by convection • Warmed rock melts under less pressure and erupts near surface • Mostly under sea floor • Seamount ---> volcanic island ---> plate shifts island away from hotspot
Plains and Plateaus
• Plains are broad flat areas that do not rise far above sea level • Extend from base of mountain range • Built by accumulated sediment • Between Rocky Mountains and Mississippi river • Georgia Coastal Plain • Much of midwestern US • Plateau flat areas uplifted > 600 m above sea level • Tectonic forces
Earth's Water
• Almost all of Earth’s water is salt water • < 3% of water is fresh water • Most held in ice and snow in polar regions and tops of mountains (we cannot use most of this water) • Groundwater-under the surface • Surface water • Atmosphere- think clouds • Biosphere- water in living things • Water is always moving in a cycle (hydrologic cycle)
Ocean Basin
• Deep depression in lithosphere between continental margin (edge of a continent) and midocean ridge • 30% of Earth’s surface • Made of oceanic crust (basaltic) • Contains abyssal plains, seamounts, and ocean trenches
Abyssal Plain
• Flattest places on Earth • Averages 4,000 m below sea level • Less than 1 ft vertical change over 1,000 sq ft (.01%) • Dark, dense, near freezing • Pressure increases with depth • Most animals eat dead organic matter
Ocean Trenches
• Deep furrow in the sea floor adjacent to active continental margins • Can exceed 10,000 meters • Edge of one tectonic place disappears due to subduction • Subducting lithosphere can become stuck b/c of friction • Earthquake • Creates heat
Midocean Ridge
• Rises from seafloor indicating divergent plate boundary • 65,000 m long • 21% of Earth’s surface • “ridge” is somewhat misleading because system is hundreds of meters wide and rift valley exist along ridge crest
Agents of Change
mediums where surface processes occur (includes liquid water, ice, gravity, and wind)
Weathering
The breakdown of rock that occurs at or near Earth's surface
What are the two types of weathering
Chemical and mechanical (physical)
Mechanical Weathering
The breakdown of rock by physical means
Erosion
The physical REMOVAL of weathered bits of rock from one place and their transport by liquid water, ice, gravity, and wind to another place
Soil is...
a mixture of organic and nonliving materials
rock fragments with decaying matter
necessary for plant growth
found in thousands of different kinds 5)composed of layers (shorthand is just to identify "topsoil" and "subsoil"; in reality, subsoil is composed of various layers or "horizons"). 6)a finite (limited) resource. (As in, fertile soil)
Components of soil
Air water rocky material Humus (5% or less, gives the black/brown color)
Soil is classified by texture
Sand (2-0.05mm) Silt(0.05-0.002mm) Clay (smaller than 0.002mm)
GEORGIA HAS MORE CLAY
Loam
The best soil, it's a mixture of sand, silt, and clay
Soil Horizons
O Horizon-below the grass, smallest layer
A Horizon-topsoil, brown/black color
E Horizon-leaching layer
B Horizon- subsoil
C Horizon- substratum, contains groundwater
R Horizon- bedrock
Stream
any body of flowing water confined within a channel (has sides)
Running water is most widespread agent of ____
Erosion (example: grand canyon)
Gradient
Slope of a stream
Velocity
How quickly water moves at a given point
Discharge
volume of water that a stream transports in a given amount of time
Load
the amount and type of sediment that a stream carries (dissolves, suspended, and bed)
Evolution of a stream
•Streams change over time.
–Initially, streams are straight and the water flows fast. (finding the route of least resistance)
–Later, streams are meandering (curve of a river)
–Stream channels deepen and widen.
Downcutting
•River erodes channel more deeply overtime
–Erosion works on sides widening the channel
–Can create valley
•V-shaped valleys
–Steep slopes
–Very common
Glaciers
•Glaciers are enormous masses of moving ice.
–formed by snow that doesn't melt
–compacted by overlying snow, becoming crystalline with a liquid base.
-between the rock and the glacier, there will be a little bit of water that they are riding on
•Two kinds: alpine and continental
Glacial Erosion
•Means of erosion:
–Abrasion
–Plucking
-can be apart of the glacier
•Evidence of glacial erosion:
–U-shaped valleys
–Striations
–Horns
–Glacial lakes- where the water in the U shaped valley meets in the middle and forms a lake
Groundwater-Change Agent
-Cave-empty underground space large enough for a human to enter
-created by dissolving action of groundwater (especially limestone)
-chemically weathering and erosion
-readily dissolves in acidic groundwater
-stalatites (from the top of the cave) vs stalagmites (from the bottom of the cave)
-Calcium carbonate and other minerals precipitate out of solution
-Over time, roof can collapse forming in a sinkhole