Fossils: Understanding Earth’s Past Life
Fossils
A fossil is any remains of a living organism or its activity that lived in another era and has reached our days transformed into a rock. This generally includes remains such as shells, eggs, leaves, or traces.
Fossilization Process
- An organism dies and is covered by sediments.
- The soft parts rot, but the harder parts remain long enough for the outer surface to be imprinted in the sediment.
- Sometimes, these hard parts are mineralized and are well preserved.
- The hard parts are dissolved, and the
Natural Resources, Ecosystems, and Environmental Challenges
Natural Resources
Life on this planet depends upon a large number of things and services provided by nature, which are known as natural resources. Thus, water, air, soil, minerals, coal, forests, crops, and wildlife are all examples of natural resources.
Renewable Resources
These are resources that can be replenished naturally within a human lifespan, such as solar energy, wind energy, water, and biomass.
Non-Renewable Resources
These are resources that exist in finite quantities and cannot be replenished
Read MoreUnderstanding the Iberian Plateau: Geography and Climate
The Iberian Plateau
The main unit is emphasized in Spanish geography and covers 45% of the surface. During the downhill movement, it is broken into two blocks: a northern sub-plateau with an altitude of 800-850 m surrounded by mountains, and a southern sub-plateau with an altitude of 500-700 m, consisting of two separated Alpine Toledo regions.
Mountain Ridges
Galicia-Massif: Lions of 200 square miles of mountainside and share of Galicia, Asturias Western Sierra, Montes de Toledo, Sierra Cabrera, and
Read MorePlant Life: Deciduous Forests, Mediterranean Flora, and Mountain Vegetation
Plant Life Across Diverse Regions
Deciduous Forests: Galicia to the Pyrenees
- Deciduous Forest: Dense, tall trees with flat, deciduous leaves. Often monospecific, dominated by oak and beech.
- Man-made Forests: Chestnut, pine, and eucalyptus plantations.
- Atlantic Scrub (Landa): Replaces degraded deciduous forests, characterized by gorse and heather.
- Marcescent Forest: Formed by oaks. Semi-deciduous leaves that dry in the fall but remain until late winter.
Mediterranean Region Vegetation
Found in the Mediterranean
Read MoreThe Solar System: Planets and Beyond
The Solar System
The Earth is the center of the universe and turns around the sun, the moon. The sun is the center of the universe.
Characteristics of Planets
- Its mass should be sufficient to give it a nearly spherical shape.
- Must have cleared its orbit.
Composition of the Solar System
- Sun: A sphere of glowing gases that releases energy through thermonuclear reactions in its core.
- Planets: Celestial bodies orbiting the sun.
- Inner Planets: (Mercury, Venus, Earth, Mars): Near the sun, small, rocky, and with
Understanding Genetics, Chemistry: Key Terms & Concepts
Key Concepts in Genetics and Chemistry
Mendel experimented by extracting traits from garden peas containing plant cells, including germinal elements, and placing them in the female gamete. He selected only 22 varieties of peas.
A gene is a specific sequence of nucleotides on one of the chromosomes, referenced to the scalar.
An allele is one of the alternative forms of a gene.
The genotype is an individual’s genetic content, their DNA.
The phenotype refers to the expression of the genotype in a specific
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