ICSI Test 4

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....

1) tectonic process
2) WATER (running, more powerful than the others)
3) wind
4) ice
5) 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...

1) a mixture of organic and nonliving materials
2) rock fragments with decaying matter
3) necessary for plant growth
4) 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

1) O Horizon-below the grass, smallest layer

2) A Horizon-topsoil, brown/black color

3) E Horizon-leaching layer

4) B Horizon- subsoil

5) C Horizon- substratum, contains groundwater

6) 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