Introduction to Biology Overview

Definition: The study of living organisms, their structure, function, growth, origin, evolution, and distribution.
Branches:
- Zoology: Study of animals.
- Botany: Study of plants.
- Microbiology: Study of microorganisms.
- Genetics: Study of heredity and variation.
- Ecology: Study of organisms and their environments.

Cell Theory:
- All living organisms are composed of cells.
- The cell is the basic unit of life.
- All cells arise from pre-existing cells.
Homeostasis: The ability of an organism to maintain a stable internal environment despite external changes.
Metabolism: The sum of all chemical reactions in an organism, including catabolism (breaking down molecules) and anabolism (building up molecules).
Evolution: The process through which species change over time through natural selection and genetic variation.

Carbohydrates:
- Primary source of energy.
- Composed of sugars (monosaccharides, disaccharides, polysaccharides).
Proteins:
- Made of amino acids.
- Functions include catalyzing reactions (enzymes), structural roles, and transport.
Lipids:
- Fats and oils.
- Important for energy storage, membrane structure, and signaling.
Nucleic Acids:
- DNA and RNA.
- Store and transmit genetic information.

Prokaryotic Cells:
- Simple, no nucleus (e.g., bacteria).
- Lack membrane-bound organelles.
Eukaryotic Cells:
- Complex, with a nucleus (e.g., animals, plants, fungi).
- Contain membrane-bound organelles (mitochondria, endoplasmic reticulum).

DNA Structure:
- Double helix composed of nucleotides (adenine, thymine, cytosine, guanine).
Gene Expression:
- Process by which information from a gene is used to produce a functional product (usually proteins).
Mendelian Genetics:
- Principles of inheritance proposed by Gregor Mendel (dominant and recessive traits).

Ecosystems: A community of living organisms interacting with their physical environment.
Biomes: Large geographical areas characterized by specific climates and ecosystems (e.g., rainforest, desert).
Biodiversity: The variety of life in the world or in a particular habitat; essential for ecosystem resilience.

Natural Selection: Mechanism by which individuals with favorable traits are more likely to reproduce.
Speciation: The formation of new and distinct species in the course of evolution.

Systems:
- Circulatory: Transports blood, nutrients, gases.
- Respiratory: Facilitates gas exchange (oxygen and carbon dioxide).
- Digestive: Breaks down food and absorbs nutrients.
- Nervous: Coordinates body activities through nerve impulses.
Immune System: Protects against pathogens and disease.

Observational Studies: Watching and recording behavior without manipulation.
Experiments: Controlled tests to determine cause-and-effect relationships.
Field Studies: Research conducted in natural environments.

CRISPR and Genetic Engineering: Techniques for editing genes.
Climate Change Impact on Biodiversity: How environmental changes affect species and ecosystems.
Stem Cell Research: Potential for regenerative medicine and treating diseases.

Study of living organisms, covering structure, function, growth, origin, evolution, and distribution.
Branches include:
- Zoology: Focuses on animal life.
- Botany: Examines plant life.
- Microbiology: Investigates microorganisms.
- Genetics: Explores heredity and variation.
- Ecology: Studies interactions between organisms and their environments.

Cell Theory:
- All organisms consist of cells; cells are life's fundamental unit.
- New cells originate from existing cells.
Homeostasis: Ability of an organism to maintain stable internal conditions regardless of external changes.
Metabolism: Totality of chemical processes within organisms, encompassing both catabolism and anabolism.
Evolution: Species undergo change over time through natural selection and genetic variation.

Carbohydrates: Main energy source, made up of monosaccharides, disaccharides, and polysaccharides.
Proteins: Composed of amino acids; functions include enzymatic reactions, structural support, and transport.
Lipids: Encompasses fats and oils; critical for energy storage and cell membrane structure.
Nucleic Acids: DNA and RNA, responsible for storing and transmitting genetic information.

Prokaryotic Cells: Simple structure lacking a nucleus; includes bacteria, no membrane-bound organelles.
Eukaryotic Cells: Complex cells with a nucleus; includes animals, plants, and fungi, featuring membrane-bound organelles such as mitochondria and endoplasmic reticulum.

DNA Structure: Composed of nucleotides; forms a double helix, consists of adenine, thymine, cytosine, and guanine.
Gene Expression: The process of translating genetic information into functional products, primarily proteins.
Mendelian Genetics: By Gregor Mendel, outlines inheritance patterns of dominant and recessive traits.

Ecosystems: Communities of living organisms interacting with their environment.
Biomes: Extensive geographical areas defined by their climates and ecosystems, such as rainforests and deserts.
Biodiversity: Represents the variety of life in a given habitat, crucial for ecosystem resilience.

Natural Selection: Process where advantageous traits enhance reproductive success.
Speciation: Development of new and distinct species through evolutionary processes.

Systems Overview:
- Circulatory System: Transports blood, nutrients, and gases.
- Respiratory System: Enables gas exchange of oxygen and carbon dioxide.
- Digestive System: Breaks down food and absorbs nutrients.
- Nervous System: Coordinates body functions via nerve impulses.
Immune System: Defends against pathogens and diseases.

Observational Studies: Record behaviors without interference or manipulation.
Experiments: Controlled methodologies to establish cause-and-effect relationships.
Field Studies: Research conducted in natural settings to gather real-world data.

CRISPR and Genetic Engineering: Modern techniques for gene editing that have transformative potential.
Climate Change Impact on Biodiversity: Examines how changing environments affect species and ecosystems.
Stem Cell Research: Investigates regenerative medicine and the potential to cure diseases through stem cell application.