Prehistoric Art: A Historical Context
Prehistoric Art: Historical Context
Prehistoric art encompasses the artistic expressions of Homo sapiens during the late Stone Age and early Metal Age. Prehistorians have divided this era into three main phases:
Phases of Prehistoric Art
- Upper Paleolithic (32,000-9,000 BC): This period occurred during the glacial environment.
- Mesolithic (9,000-6,000 BC): This era marked a transition period.
- Age of Metals: This phase includes the Copper Age (3,000-2,000 BC) and the Bronze Age (2,000-725 BC).
During these
Read MoreAcid Deposition, Climate Change, and Energy Production: An Environmental Overview
– Acid Deposition
Acid deposition refers to acid coming down from the air to the ground, usually in the form of rain (or snow). This is known as wet deposition. Dry deposition comes from ash or particles.
Acids are chemicals that can donate a hydrogen atom. They are measured by the pH scale. Solutions with a pH below 7 are acidic, while solutions with a pH above 7 are alkaline.
Normal unpolluted rain is slightly acidic with a pH of 5.6, but pollutants can lower it to as low as 2 pH.
Air Pollutants
Air
Read MoreA Comprehensive Guide to Geological Processes and Landforms
Geologic Cycle
Endogenic Processes
These are internal processes, such as plate tectonics and magma upwellings.
Exogenic Processes
These are external processes, such as wind, water, and erosion.
Igneous Rocks
Igneous rocks are formed from the cooling and solidification of molten rock material.
Magma
Magma is molten rock found beneath the Earth’s surface.
Lava
Lava is magma that has extruded onto the Earth’s surface.
Examples of Igneous Rocks
- Granite
- Basalt
Intrusive Igneous Rocks
Intrusive igneous rocks cool and
Read MoreEnergy: Sources, Consumption, and Environmental Impacts
Electricity
An electrical generator is a spinning coil of wire within a magnetic field. As the generator turns, the coils spinning through the magnetic field generate a voltage along the loop. The voltage is determined by the number of loops in the coil.
AC current moves back and forth with the changing magnetic field. As the coil of wire spins through the changing magnetic field, it produces a voltage going one way, but when the coil is 180 degrees from its initial starting point, it goes back and
Read MoreSurveying Examination Study Guide: Key Concepts and Definitions
SURVEYING EXAMINATION QUESTIONS
Land Survey
Land survey is the process of making all necessary measurements of an area of interest to obtain a topographical map.
Stakeout
Stakeout is the process of identifying in the field, using surveying techniques, all the details necessary for the development of works related to a project.
Maps and Types
A map is a flat representation of the land surface or a part thereof, whose large extension requires the use of cartographic methods. Their scales are generally small.
Genetics, Biotechnology, and Natural Resources: A Comprehensive Overview
XIX Century Classical Genetics. XX Century Molecular Genetics
Nucleic Acids: Nucleotides
Consisting of:
- Sugar (Pentose + nitrogenous base)
- Phosphoric Acid
DNA
AT antiparallel strands, CG (semiconservative replication)
RNA
A string AU, CG
Genetic Code
Replication, Transcription, Translation (5′ to 3′)
Mutations
- Gene: (changes, additions, and deletions)
- Chromosomal: (deletion, inversion, translocation, and duplication)
Biotechnology
Techniques that use living things to our benefit.
Genetic Engineering
Techniques for
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