Key Concepts in Biology

Cell Theory:
- All living organisms are composed of cells.
- The cell is the basic unit of life.
- All cells arise from pre-existing cells.

Prokaryotic Cells:
- Lack a nucleus and membrane-bound organelles.
- Example: Bacteria and Archaea.
Eukaryotic Cells:
- Contain a nucleus and membrane-bound organelles.
- Example: Plant, animal, and fungal cells.

Carbohydrates:
- Composed of sugars; provide energy and structural support.
Proteins:
- Made of amino acids; function as enzymes, hormones, and structural components.
Lipids:
- Fats and oils; involved in energy storage, insulation, and cell membranes.
Nucleic Acids:
- DNA and RNA; store and transmit genetic information.

DNA Structure:
- Double helix composed of nucleotides (A, T, C, G).
Genes:
- Segments of DNA that code for proteins.
Mendelian Genetics:
- Principles of inheritance based on dominant and recessive traits.

Natural Selection:
- Mechanism of evolution where organisms better adapted to their environment tend to survive and reproduce.
Speciation:
- The process by which new species arise.

Ecosystems:
- Community of living organisms interacting with their environment.
Biomes:
- Large geographical biotic communities, e.g., forests, deserts, tundras.
Nutrient Cycles:
- Processes that recycle nutrients through the ecosystem (e.g., carbon, nitrogen cycles).

Organ Systems:
- Groups of organs that work together (e.g., circulatory, respiratory, digestive systems).
Homeostasis:
- The maintenance of stable internal conditions.

Genetic Engineering:
- Manipulation of an organism's genome using biotechnology.
CRISPR:
- A tool for editing genes, allowing for precise modifications.

Biodiversity:
- The variety of life in the world, critical for ecosystem health.
Endangered Species:
- Species at risk of extinction due to habitat loss, pollution, and climate change.

This summary covers essential concepts in biology, providing a foundational understanding of the subject.

Cell Theory emphasizes that all living organisms consist of cells, which are the fundamental units of life, and that cells originate from pre-existing ones.

Prokaryotic Cells are simple, lacking a nucleus and membrane-bound organelles; examples include Bacteria and Archaea.
Eukaryotic Cells are more complex, containing a nucleus and membrane-bound organelles; examples include plant, animal, and fungal cells.

Carbohydrates are sugar-based molecules that provide energy and structural functions in organisms.
Proteins are polymers of amino acids serving as enzymes, hormones, and structural components critical for various biological processes.
Lipids comprise fats and oils that play key roles in energy storage, insulation, and forming cell membranes.
Nucleic Acids include DNA and RNA, essential for storing and transmitting genetic information across generations.

DNA Structure is characterized by a double helix formed from four nucleotides (adenine, thymine, cytosine, guanine), which serve as the genetic blueprint.
Genes are specific DNA segments that carry instructions for protein synthesis.
Mendelian Genetics lays the groundwork for inheritance patterns, focusing on dominant and recessive traits in offspring.

Natural Selection is a driving force of evolution, favoring organisms best suited for survival and reproduction within specific environments.
Speciation refers to the process through which new species emerge, often due to genetic divergence over time.

Ecosystems represent interactions among living organisms and their physical environments, forming a dynamic web of life.
Biomes are large ecological areas on the planet, like forests, deserts, and tundras, categorized by climate and biological diversity.
Nutrient Cycles, such as the carbon and nitrogen cycles, illustrate the recycling of essential nutrients within ecosystems, crucial for sustaining life.

Organ Systems are composed of interconnected organs working collaboratively, such as the circulatory, respiratory, and digestive systems, to maintain physiological functions.
Homeostasis is the biological process of maintaining stable internal conditions, crucial for optimal functioning.

Bacteria are single-celled organisms that can either be beneficial (e.g., gut microbiota) or pathogenic (causing diseases).
Viruses are acellular and require a host organism for replication, highlighting their unique status in the biological world.

Genetic Engineering constitutes the manipulation of an organism's genome using various biotechnological techniques to achieve desired traits.
CRISPR is a powerful gene-editing tool allowing scientists to make precise alterations in DNA sequences, enhancing possibilities in genetic research.

Biodiversity represents the variety of life forms on Earth, crucial for ecosystem health, resilience, and function.
Endangered Species are those at risk of extinction due to factors like habitat destruction, pollution, and climate change, emphasizing the need for conservation efforts.